vt^'rw M00mi mnm ■■^'AH/ v^i5^^>^'^,-,"A^^S ^'^nnC^^ -^ " ■: >iv ' .' *t UAy>^ *vUWaa/ 1 ' BOUGHT WITH THE INCOME PROM THE SAGE ENDOWMENT FUND ^^M THE GIFT OF iMMM^ Benirg W. Sage 1891 ENGINEERING LIBRARY A.J/SUf.. 'm/^^^^ Cornell University Library QE 262.N77F79 1886 The geology of the country around Northa 3 1924 004 543 264 Cornell University Library The original of tiiis book is in tine Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924004543264 MEMOIES OF THE GEOLOGICAL SUMEY. ENGLAND AND WALES. THE GEOLOGY OE THE COUNTRY AROUND NORTHALLEBTON AND THIRSK. (EXPLANATION OF QUARTER-SHEETS 96 N.W. AND 96 S.W.j NEW SERIES, SHEETS 42 AND 52.) BY 0. FOX-STRANGWAYS, F.G.S., A. G. CAME EON, AND G. BARROW, F.G.S. PUBLISHED BY OEDEE OP THE L0ED8 COMMIBSIOSEES OP HEE MAJESTY'S TEEASTTEY. LONDON: PRINTED FOB HER MAJESTY'S STATIONERY OFFICE, AND SOLD BY ioKGMANS & Co., Paternoster Row; Tbcbnek & Co., Ludgate Hill; Letts, Son, & Cp., Limited, 33, King Williain Street ; Edwaisd Stanfokd, Junior, 55, Charing Cress ; J. Wyld, 12, Charing Cross ; and B. Qttakitoh, 15, Piccadilly; also by T. J. Day, 53, Market Street, Manchester ; Messrs. Johnston, 4, St. Andrew Square, Edinburgh ; SoDQES, Figgis, & Co., 104, Grafton Street, and A. Tkom & Co., Limited, Abbey Street, Dublin. 1886. Price One Shilling and Sixpence. LIST OF GEOLOGICAL WIAPS, SECTIONS, AND PUBLICATIONS OF THE GEOLOGICAL SURVEY. , The Maps are those of the Ordnance Survey, geologically coloured by the GeolOBical Survey of the united Kingdom nnd«|^ ) (r'o'i"'aXttTanS'M^"oT;s^^^^^^^^ tions, see " Catalogue." Pnce 1«.) ENGLAND AND WAlES.-(Scale one-inch to a mile.) Maps marked • are also puhlished as Drift Maps. Those marked t are published only as Drift Maps, Sheets 3*. 5, 6», 7», 8, 9, 11 to 22, 25, 26, SO, 31, SS to 37, 40, 41, 44, 4T*, 61*, price 8». 6d. each. 1021 HOiuzoirTA.'x. sBCTZows, vaaxiCAi sbctiows. 1 to 139, England, price 5s. each. 1 to 72, England, price Ss. 6d. each. COMPLETED COVNTZES OP EN'CIiAH'D AXm VTAIES, on a Scale of one-ineh to a Mile. Sheets marked • have Descriptive Memoirs. Sheets or Counties marked t are illustrated by General Memoirs ANGLESE It,-77 (N), 78. Hor. Sect. 40. BEDFORDSHIBE,— 46 (N'W,NE, SWt, & SEt), 52 (NW, NB, S"W,& SE). BERKSHIEE,— 7*, 8t, 12*, 13*, SI*. 45 (SW*). Hor. Sect. 59, 71, 72, 80). BRECKNOCKSHIRE^,— 36, 41, 43, 56 (NW & SW), 57 (NE & SB I. Hor. Sect. 4, 5, 6, 11, and Vert. Sect. 4 and 10. BU0KINGHAMSHIRE,-7* IS* 45* (NE, SE), 46 (NW, SWt), 53 (SW). Hor. Sect. 74, 79. CABRMARTHENSHIEEt, 37, 38, 40, 41,42 (NW & SW), 56 (SW),57 (SW& SE). Hor.Sect.2, 3, 4, 7. 8, 9; and Vert, ' Sect. S, 4, 5, 6, 13, 14. ' CAERNABVONSHIRE,t-74 (NW), 75, 76, 77 (N), 78, 79 (NW & SW). Hor. Sect. 38, SI, 40. CARDIGANSHIREt,-40, il, 56 (NW), 67, 68, 59 (SE), 60 (SW). Hor. Sect. 4, 5, 6. CHESHIRE,-73 (NB & NW), 79 (NE & SE), 80, 81 (NW* & SW*), 88 (SW). Hor. Sect. 18, 43, 44, GO, 64, 65, 67, 70. CORNWALLt,— 24t, 25t, 26t, 29t, 30t, 31t, 32t, & 33t. DENBIGHt,— 73 (NW), 74,75 (NE), 78 (NE SE), 79 (NW, SW, SE),80 (SW). Hor.Sect. 31, 35, 38, 39, 43, 44 ; & Vert. Sect. 24, DBRBYSHIREt,— 63 (NE), 63 (NW). 71 (NW, SW, 8E),72 (NE, SE), 81, 82, 88 (SW, SE). Hor. Sect. 18, 46, 60, 61, 69, 70, DBVONSHIREt,-20ft 21t, 32t, 23t, 24t, 25t, 26t,& 27+. Hor. Sect. 19. DORSETSHIRE,— 15, 16, 17, 18, 31, 22. Hor. Sect. 19, 20, 21, 22,56. Vert. Sect. 23. ESSEX,— It. 2, 47*, 48. Hor. Sect. 84, 120. I'LINTSHIRBt,-74 (NE), 79. Hor. Sect. 43. GLAMORGANSHIREt,— 20, 36, 37, 41, & 42 (SE & SW). Hor. Sect. 7, 8, 9, 10, 11; Vert. Sect. 2, 4, 5, 6, 7, 9, 10, 47. GLOUCESTERSHIRE,— 19, 34*, 35, 43 (NB,SW,SB), 44*. Hor. Sect. 12 to 16, 69 ; Vert. Sect. 7. 11, 15, 46to51. HAMPSHIRE,— 8t, 9t, 10*, lit, 12*, 14, 15, 16. Hor. Sect. 80. HEREFORDSHIRE,— 42 (NE & SE), 43, 56, 66 (NE & SE). Hor.Sect. 5, IS, 27, 30, 34 ; and Vert. Sect. 15. KENTt;— it (SW & SE), 2t, St. 4', 6t. Hor.Sect. 77 and 78. , MBEIONETHSHIREt,— 59 (NB & SB), 60 (NW), 74, 75 (NB & SE). Hor. Sect. 26, 28, 29, 31, S2, 35, S7, 38. 39. MIDDLESEXt,-lt (NW & SW), 7', 8t. Hor. Sect. 79. MONMOUTHSHIRE,— 35, 36, 42 (SE & NE), 43 (SW). Hor. Sect. 5 and 13 ; and Vert. Sect. 8, 9, 10, 12. MONTGOMERYSHIREt,— 66 (NW), 59 (NE 4 SB), 60, 74 (SW & SE). Hor. Sect. 26, 27, 29, SO, 32, 34, 35, 36, 88. NORTHAMPTONSHIRE,-64, 45 (NW & NE), 46 (NW), 62 (NW, NE, & SW), 53 (NE, SW, & SE),6S (SE), 64. OXFORDSHIRE,— 7*, IS*, 34*, 44*, 45", 53 (SB*, SW). Hor. Sect. 71, 72, 81, 82. PEMBROKBSHIREt,— 38, 39, 40, 41, 58. Hor. Sect. 1 and 2 ; and Vert. Sect. 13 and IS. RADNORSHIRE,— 42 (NW & NE), 66, 60 (SW & SE). Hor. Sect. 5, 6, 27. EUTLANDSHIREt,— this county is wholly included within Sheet 64.* SHROPSHIRE,— 55 (NW, NE), 56 (NE), 60 (NB, SE), 61, 62 (NW), 73 74 (NE, SE). Hor. Sect.24, 25, 30, SS, 34, 36, 41, 44, 45, 53, 54, 38 ; and Vert. Sect. 23, 24. SOMERSETSHIRE,— 18, 19, 20, 21, 27, 85. Hor. Sect. 15, 16, 17, 20, 21, 22 i and Vert. Sect. 12, 46, 47, 48, 49, 50, 51. STAFFORDSHIRE,— (64 NW), 55 (NE), 61 (NE, SE), 62, 63 (N W), 71 (SW). 72, 73 (NE, SE), 81 (SE, SW), Hor. Sect. 18, 23, 24, 25, 41,.42, 45, 49, 64, 57, 61, 60: and Vei't. Sect. 16, 17, 18, 19, 20, 21, 23, 26. SUFFOLK,— 47,* 48,* 49, 60, 51, 66 SE,* 67. SURREY,— 1 (SWt), 6t, 7*, 8t, 12t. Hor. Sect. 74, 76, 76, and 79. SUSSEX,- 4*, 6t, 6t, St, 9t, lit. Hor. Sect. 73, 75, 76, 77, 78. WARWICKSHIRB,-44*, 45 (NW), 6S*, 54, 02 (NE, SW, SB), 63 (NW, SW, SE), Hor. Sect. 23, 48 to 51, 82, 83; Vert. Sect. 21. WILTSHIRE,— 12*, 13*, 14, 16, 18, 19, 34*, and 35. Hor. Sect. 15 and 69. WORCESTERSHIRE,— 43 (NE), 44*, 54, 66,62 (SWSE),61 (SB). Hor. Sect. IS, 23,25.60, 69, and Vert. Sect. 15. GENEBAXi MEniOZBS OF THE GEOiLOCICA]^ SITRVE'T. REPORT on C0RN\VALL,.DEVON, and WEST SOMERSET. By Sir H. T. De Li Beche. 14s. (O.P.) FIGURES and DESCRIPTIONS of the PALiEOZOIC FOSSILS in the above Counties. By Pbof. PaixLiPS. (O.P.) The MEMOIRS of the GEOLOGICAL SURVEY of GREAT BRITAIN. Vol. I., 21s. ; Vol. II. (in 2 Parts), 42s. NORTH WALES. By Sib A. C. Ramsay. Appendix, by J. W. Salieh and E. Etheeidob. 2nd Ed. 31». (Vol. IIL of Memoirs, &c.) The LONDON BASIN. Part I. Chalk and Eocene Beds of S. and W. Tracts. By W. Whiiakee. ISs. {Vol. IV. of Memoirs, &-c.) Guide to the GEOLOGY of LONDON and the NEIGHBOURHOOD. By W. Whiiakee. 4th Ed. Is. The WEALD (PARTS of the COUNTIES of KENT, SUEEEY, SUSSEX, and HANTS). ByW.ToPiET. 17s. 6-17 - 15 Of these beds (a) and (b) unquestionably belong to the Rhsetic Beds and (e) to the Lias. From the close resemblance of (c) to the " White Lias " it has been included with the Rhsetic Beds, but no fossils were found in it. The beds (d) are very similar to those above and contain the same fossils though in a dwarfed form, but as they do not include Avicula contorta they have been mapped as the basement bed of the Lias. This section is given first, in order that the bearing of the various small exposures to be described may be better understood. On the west side of Harlsey Castle the brown paper shale and Pleuromya limestone are seen, showing, the base of the Lias, while a little further south are old gypsum pits in the highest beds of the New Eed Marl. The Rhsetic Beds form a clear low escarpment between Harlsey Castle and Park House, and the brown paper shales are well exposed in the small plantation on the east side of the road a quarter of a mile north of Park House. Gypsum and gypsiferous marls crop out between Park House and Winton ; and the paper shales are next found at a much lower level at the foot of the small stream which joins Winton Beck just south of Winton. To the west of this place the same limestones and the Tea- Green Marls are occasionally ploughed up, but there is no very clear evidence till Hallikeld Farm is reached. In the small stream or ditch running from the Brick Works here, we come upon shales with the Pleuromya limestone, and just against the duck pond below the farm more shale is seen belonging to the beds {d). Below this the section ceases, but a little to the west, at a some- 14 EH^TIC BEDS. what higher level, are a series of drifts made quite recently into the gypsum beds at the top of the New Red Marl, proving a fault here, with an upthrow to the west of some 30 feet or rather more. This gypsum was worked many years ago, and the line of old pits clearly marks the base of the Rhistic Beds for some distance further south. Proceeding up the south side of the hollow above Harrogate we come first upon a series of old pits with much red marl lying about. Immediately above the highest the Tea-Grefen Marls are seen, the little hard Bone Bed at their top forming a well-marked terrace, and fragments of the hard siliceous band with Isodonta Ewaldi may be picked up along its outcrop. The soft Avicula cmitorta shales are not exposed, but the upper part of the White Lias is seen resting beneath the papery shales of the Lower Lias immediately on entering the small plantation. In both of the roads to the south of this the little hard Bone Bed is seen with red marl at no great distance below. In Dibdale there is a fairly good exposure of these beds, the little scrub-covered bank on the north side being capped by the lowest band of Pleuromya limestone. Exactly below where this is first seen red and green marl outcrops in the stream, and higher up green marl is seen, while some way up the bank fragments of the White Lias Limestone are scatter red about. Still further up the White Lias shale crops out, after which there is a blank, for some yards ; but the lowest beds of paper shale with the charac- teristic limestones are turned out in great profusion through the long new plantation to the east. Thus the base and top of the Rhsetic Beds are well seen, but the soft Avicula contorta shales are, as usual, covered up. Some 200 yards north-west of Crosby Cote there occurs the best section of the Rhsetic Beds to be seen in this district. Conamencing where the little stream splits into two, red marl is seen in both branches, and fragments of the Bone Bed may be found along the sharp feature which it makes between the two streams. Passing up the southern branch the following beds may be made out in descending order : — Ft. In. Paper shales, with Pleuromya erowcombeia, Cardium phillipianum (f), small and flattened. About 20 feet of these beds are seen altogether, but the section is not continuous A series of pits has been sunk in the upper part of these beds, but they are quite filled up and grown over - - 20 Whitish shale (White Lias), about 10 feet; no fossils seen, and the top is obscure - - 10 Dark, pyritous, crisp shales, with Avicula contorta along, certain lines, 8 feet- . - 8 Hard, white, siliceous rock, wavy-bedded, about 3 inches thick. Contains Isodonta Ewaldi and Cardium phillipianum (.?), also fragments of encrinite stems - ' - . . - 3 Dark shale, 7 feet, Avicula contorta very abundant again along certain definite lines - .70 RH^TIC BEDS. 15 Ft. In. Hard laminated shale, about 6 inches, Avicula con- torta abundant. Fish scales and Isodonta Ewaldi fairly common - - - - - 6 Close-grained siliceous bed crowded with Isodonta Ewaldi. These last two represent the bone bed - 6 Dark shale, about 1 foot 6 inches - - 1 6 Tea-Green Marl, about 5 feet seen - - - 5 Some 15 or 20 feet below this Red and Green Marls are seen. On the south side of Crosby Cote just under the overflow sluice of the fish pond is the only clear section of the actual junction of the Lias and Rhaetic Beds. Some 7 or 8 feet of shale, platy at first but becoming lighter and more argillaceous, rests upon a small bed of white argillaceous limestone, this again resting on the white shales. At Crosby Cote there are two wells sunk about 5 feet in blue shale, the water from which is strongly impregnated with sul- phuretted hydrogen. The following are the analyses of these waters* :— Well in the Parle, smith Well in the Courtyard. of the House. Grains per Gallon. Grains per Gallon. Solid matter - - 66-50 38-15 Chlorine - - - 7' 28 2-89 Equalto Chloride of Sodium 12-04 4-06 Nitrogen as Ammonia ' - '0065 -0014 as Albuminoid - -0014 -0196 as Nitrates - -0044 -1900 Hardness - - - 31° 22-7 Hardness after boiling - 24° 11-1 Solid matter, chiefly carbonate and sulphate of lime. In a wood about 300 yards north of Thornton-le-Beans is a very clear section of the basement beds of the Lias. The first 25 feet of the section shows paper shales with thin limestones, Ostrea liassica being fairly abundant in the uppermost ; the lowest bed being the well-known Pleuromya limestone, which is almost built up of that shell. Below this come somewhat similar shales with flattened, dwarfed specimens of Pleuromya and Cardium. There is nearly 15 feet of this shale, and it is so much lighter in colour at the base that it is probably within a foot or two of the " White Limestone." Again, in the small stream close to Thornton-le-Beans, in the south bank, the lowest limestone is well seen, the shales below being clearly exposed and identical in appearance with those seen in the wood just referred to. A noticeable point here is the occurrence of a hard sandy band just below the limestone, containing casts of an Ostrea, probably Ostrea liassica, but this is not quite clear. At the foot of the bank, which is some 15 feet high, the beds are very light coloured, and we are again within a foot or so of the White Lias. On the south side of Thornton-le-Beans the Ehsetic Beds are thrown up by a fault, and being covered by Boulder Clay do not * Supplied by Mr. T. Bell. 16 EH^TIC BEDS. make so good a feature ; the outcrop is therefore more obscure, but the green marls are seen at several places, and shales above have been proved in the following well-sections, which afford some assistance in tracing the lines near here : — Salikiln. — This well is bricked ; it is said to be 42 feet deep in blue shale. Summer Carr. — Blue shale on red marl with much gypsum, 72 feet to bottom of well. Hill Top. — Three wells, all in blue shale, 51, 21, 20 feet deep respectively ; the last changes to a rough sand at the bottom. Purgatory*. — Fifteen feet of dark shale. Near Thornton-le-Moor the paper shales are seen at a few places, and fragments of the Bone Bed are occasionally met with. West of Thornton-le-Street the outcrop is hidden by Boulder Clay, but the Tea-Green Marl and black shales above are seen in Big Wood near Wood End. On the outlier to the west of this at Abel Grange the well went into shales belonging to the Lower Lias, while on the west face of the little hill is an opening in the Tea-Green Marl. South of Wood End the beds curve round to the east, and are not again seen till a very small outcrop is reached near South Kilvington. This occurs in a field at the north side of the first bend in the road leading to Kilvington Hall ; where, by removing the surface soil to make a small pond, the black shales with Avicula contorta have been exposed. At Plump Bank, about a mile east of Thirsk, black shales with thin limestones were turned up in laying the water pipes for the town supply. The highest of these contained Ostrea liassica and were clearly of Lias age, but the lowest shales exposed probably form part of the Ehsetic Beds, though they were too decomposed to be sure of their age. This little feature at Plump Bank, though covered further south by thin drift, is clearly visible as far as Bagby, where the lowest beds of the Lias are dug out of the wells close to the surface ; but beyond this, the outcrop of paper shale above the Rhsetic Beds in Thirkleby Park is the only clue to their position. The two great east and west faults shift the Rhsetic outcrop some miles westward and its position between them is purely hypothetical. To the south of these faults its position is at first fairly clear, being proved by the upper limit of the New Red Marl about Sessay, and by the gypsum workings at Little Sessay. A little to the east of the latter village there is a farm house, the well of which is sunk through the Tea-Green Marl of the Rhsetic Beds. In the new junction railway at the south end of Sessay Wood a gre,at quantity of paper shale was exposed, which although not quite in place could not be far removed ; while a boring at Pilmoor Cottages and the wells in the neighbourhood help to give an approximate outcrop near Pilmoor Junction, but further south the country is so completely covered by the great sheet of Warp that no attempt is made to carry on the lines. * T. P. on one inch map. 17 CHAPTER V. THE LIAS. Lower Lias. In the district here described the Lower Lias consists of a mass of dark slightly sandy shales, with hard marly bands in the lower part. Owing to the covering of drift in the great plain in which these beds outcrop, the type of country that they form is only seen in two districts ; the first between Thirsk and Northallerton on their east side ; the second, which is not so well marked, to the south-east of Thirsk, about Bagby. It may be noted that at the foot of the main escarpment the steep lower part consists of the shales without marly bands ; and these same shales extend in a broad, more or less drift-filled hoUow, for some distance to the west. The rise of the beds in this direction brings up the marly bands, which form a low table-land, having at its base the escarpment of the Rhaetic, Beds overlooking the Vale of Mowbray. At the foot of the great northern escarpment, near Cold Moor and Cringley Moor, the ixpper beds of the Lower Lias are well seen in landslips or scars that occur at intervals ; two of these show as much as 150 feet of shale with rows of ironstone nodules containing Ammonites capricornus. To the west of this the drift creeps up the hill, only one small section being seen in the stream just below the entrance to Scugdale ; from this Messrs. Tate and Blake* record Myoconcha decorata and Modiola scalprum. The bottom of Scugdale itself is entirely filled with superficial deposits, but passing over the watershed into Raisdale a small section of Lower Lias is seen just south of the fault. A considerable exposure occurs in the bottom of the eastern branch of the dale north of this forming a small inlier ; while some distance to the east, just above the junction with Bilsdale, shales of this horizon are seen in the high bank on the south side of the stream. Returning to the area about the main escarpment, the upper- most beds of the Lower Lias are seen close against the fault in the north-east face of Whorl Hill. In the railway cutting just west of Whorl Castle soft shales with A. arm,atus are seen, and a few yards north of this the first of the marly bands appears. This forms the top of the zone of A. oxynotus of Tate and Blake ; while the marly beds with Gryphma incurva, seen in the roadside by Potto Hill Farm, belong to their zone of A. Bucklandi. Along Limekiln Bank and further west no outcrops are seen at the foot of the hill owing to a thick covering of detritus and * See Tate and Blake, Yorkshire Lias, p. 99. 18 LOWER LIAS. drift, and in Mount Grace Wood only little patches are exposed in the footpaths washed bare by the rain. The junction of the Middle and Lower Lias is very clear under Thimbleby Lodge and in the Cod Beck, and exposures of shale occur for some distance below. Passing down the stream, just at the ford below Ellerbeck Mill, shales with calcareous bands are seen with a considerable number of fossils, the following being recorded by Messrs. Tate and Blake: — * Ammonites semicostatus. „ hisulcatus. Nautilus striatus. Belemnites acutus. Gryphcea incurva. Cardinia crassiuscula. „ Listeri. Lima succinia. lAma gigantea. „ pectinoides. Peclen Ttiiollieri. Pinna Hartmanni. Unicardium cardioides, Lucina limhata. Cidaris Edwai'dsi. Further down the stream, in the neighbourhood of Foxton, there are several exposures in the Lower Lias, the best of which are in Foxton Wood. A few obscure exposures are seen in the moat at Sigston Castle, in the road at the Manor House, and further north in the little stream at Willowtree House, the latter being in rather higher beds than the other sections. Between the main escarpment and the faulted 'outlier on which the village of Borrowby stands there are no exposures of Lower Lias, but to the west of the latter hill they are fairly numerous. In the woods under Landmoth the calcareous bands with Gryphcea incurva are frequently seen, resting in one place against the Jet- rock of the Upper Lias. To the west of Cod Beck is a low flattish plateau formed of these harder bands of the Lower Lias. The beds beneath form the upper part of the low hiU facing Northallerton and Thirsk, and these beds are seen at intervals along the hill. Commencing at Hallikeld Farm, platy shales with fragments of calcareous bands containing Ostrea liassica crop out just south of the house ; and the lowest beds of Lias are exposed at Harrogate, Dibdale, Crosby Cote, and Thornton-le-Beans. At North Ealvington, just to the east of Spittle Bridge, a thin band of hard limestone is seen dipping north ; and further up this stream, near Crake Bank, is a small outcrop of soft shale contain- ing small specimens of Ammonites armatus. Ftirther south another siliceous limestone, similar to the above, is seen in Whitelas Beck near Grizzle Field House, north of Feliskirk Lane. Some distance north of Thirsk the outcrop of the lowest beds of the Lias turns eastwards but is obscured by drift as far as Plump Bank ; where, in laying the pipes for the water supply of Thirsk, shales with the thin Ostrea liassica limestones were turned up on the summit of the hill'; while fragments of the * See Tate and Blake, Yorkshire Lias, p. 67. LOWER LIAS. 19 Pleuramya limestone which are scattered about, would seem to mark the top of the Rhaetic Beds. The paper shales with Ostrea liassica were proved in the wells at Bagby, the small hill immediately to the west being the escarp- ment of the Ehsetic Beds veiled by drift. The same shales may be seen in a ditch in Thirkleby Park, close to the road opposite Stockhill Green. The lower shale beds are also met with in the cellars at the Hall, and in the beck at Great Thirkleby. A little further south a great fault, having a throw of over 700 feet, shifts the outcrop of these beds some miles to the west. Barf Hill being composed of Middle Lias, the upper limit of the Lower Lias is evidently at the western foot of it. The only other evidence of these beds between the faults is seen in the Swale below TopclifFe, where shale with hard calcareous bands, outcrop on the edge of the river, and the chief fossils are Lima gigantea and Gryphoea incurva ; so that we are still some distance above the base. South of the long strip of higher beds let down between the two great Coxwold faults, the outcrop of the several divisions of the Lias is in many places hidden by the thick covering of drift and alluvium; several small faults which have broken up the beds have rendered the stratigraphy here somewhat intricate. From the position of the Keuper Marl and Rhsetio Beds at Sessay, and the Middle Lias at Hutton Sessay and Thormanby, it is evident that the Lower Lias must come on between these places, although it has not been met with to our knowledge anywhere in this area. At Carlton Husthwaite " grey shales " are said to be met with at a depth of 12 yards, but there is not much evidence as to what the shales are. The first place that the Lower Lias is really exposed is in the railway cutting near Husthwaite Station. There is not much of the bed seen here, but the outcrop along the valley towards Coxwold may be easily made out by the position of the Middle Lias in the bank above. In the country to the south towards Easingwold the position of the Lower Lias is even more obscure, and its outcrop can only be inferred by tracing the beds above. Middle Lias, In the northern half of the area here described the Middle Lias is divisible into two parts. The upper or Ironstone Series consists of rather soft shales with ironstone bands of varying thickness ; the lower or Sandy Series is composed of thin flagtry sandstones and sandy shales, with beds of Gryphcea, Cardium, &c., constituting a sandy mar). As we follow these beds southwards, the upper part becomes so sandy in nature that the distinction gradually ceases to hold good; the outcrop is also often very 20 MIDDLE LIAS. obscure, and the beds being much diminished in thickness it has been found advisable to map the Middle Lias as one division. Sandy Series. — These beds first enter the area under conside- ration at Broughton Plantation. Here, and throughout almost the entire length of their outcrop in the escarpment, they form a finely marked step-like feature in the face of the hill, by which they may be easily traced. The Sandy Series is well exposed in Tom Gill Scar in Carlton Bank, and consists of sandstones and thin shales with shelly bands for the first 35 feet ; below which is about 40 feet of sandy shale, still rather hard, with the usual characteristic bands of Gryphcea cymbium at the base. As a rule, the great scars of Lower Lias are capped by these basement beds of the Middle Lias, so that along the face of Dromonby Bank sections are fairly numerous and clear. In the eastern of the two upper branches of Raisdale these beds form two flat topped terraces, the little stream cutting a narrow gorge between and exposing a small part of the Lower Lias. The junction of the latter with the Sandy Series is well marked in the stream at the low end of the dale, the Gryphcea bands being strongly developed. Only the upper beds crop out in the western dale, forming as usual a flattish area round the stream in which the calcareous flags are seen at intervals, especially about Broomflat. In the main valley of Raisdale the Sandy Series is suddenly faulted up near High Crosslets, from which place these beds trend south-east and east, the whole of them being shown in Hartman GUI. On the north side of the dale a considerable part of the series is faulted out, but small outcrops are visible about West Cote and Cock Flat. Eeturning northwards the flaggy beds are well seen at the north end of Whorl Hill, and on the east side of the great fault the Cardium truncatum sandstones He right against the Upper Lias. Nearer Swainby Mines the ground is entirely drift covered, and for some distance along the north side of Scugdale the Sandy Series is faulted out ; the first exposure being in a small stream below Scugdale Hall. In the main stream there is only one section of thin sandstone, the superficial deposits completely covering the bottom of this dale throughout its entire length ; but to the south the beds are at a somewhat higher level and rise clear, of the drift. The position of the series is in consequence marked by the well-known terrace, and good sections are seen about Holiday House. To the west of Harfa Bank the outcrop is thrown up by a considerable fault, and beyond this is clear of drift for a great distance. Still, in passing through Limekiln Bank Woods, the downwash is sufficiently thick to obscure the rocks till the road up to Scarth Nick Is reached, where there is a clear section of the whole series. The large fault at Scarth Nick throws these beds down below the level of the drift, and they are completely obscured till the MIDDLE LIAS — SANDY SERIES. 21 outcrop is thrown up again by another fault round the north-west corner o£ the escarpment. Throughout the Arncliffe Woods small fragments of the characteristic sandstones may be picked up, and the actual junction of the Middle and Lower Lias is well seen below Lady's Chapel. There are several exposures in Far Clack Wood, Clack Wood, and the road between them, after which the drift again creeps up the hill side and obscures the strata. In Oak Dale the little stream cuts right through the sandy series, the following being a brief summary of the section. At the top comes the usual alternation of thin sandstones and sandy shales, below which is the typical sandstone, some 12 feet thick, crowded with fossils. The chief of these are Cardium truncatum, Gryphcea cymbium, Dentalium giganteum, and Pecten (equivalvis. Some 15 feet of sandy shale separate the last bed from a shaly sandstone, 10 feet thick, containing the usual Gryphcea beds near its base. At the weir above Osmotherley Corn Mill thin lenticular sand- stones, with alternating bauds of sandy shale pass completely up into the Ironstone Series, so that the lithological boundary be- tweeen the two divisions is ceasing to exist, the whole Middle Lias becoming more arenaceous. About Thimbleby there are only a few small exposures ; but south of Nuii House, at a small hollow in the hillside, the follow- ing section is seen. Section at Nun House, near Over Silton. § m f ■§ .a J Soft grey shale . . . - g §3 I Ironstone, shelly, oolitic, Avicula Seam - ^'^ L Ferruginous shale with nodules «"i= Ft. In 5 1 1 6 18 5 1 12 Lenticular sandstone " dogger," resting on sandstone with thin shale partings . - - . Shaly sandstone - . . . . Hard flaggy sandstone, with Cardium truncatum m [Soit ruhbly sandstone, with Gryphcea bands at base This is probably an under estimate, and 40 feet would be more exact ; but, considering that on the coast the beds in one place attain a thickness of nearly 100 feet, it is evident that they are slowly dying away in a south-westerly direction. There is, moreover, only six feet of shales below the Avicula Seam in this section, whereas further N.E. there is as much as 25 feet. For some little distance to the south the outcrop of the Sandy Series is clear, and exposures numerous ; but after rounding the corner of the escarpment at Over Silton the drift creeps up the hill and hides these beds for several miles. In the outlying hUl of Upsail the Cardium truncatum sandstones may be seen in the road below Upsail Castle, after which no exposures occur till Hole Wood south of FelisMrk Village is reached, where fragments 22 MIDDLE LIAS — IRONSTONE SERIES. of sandstone and sandy shale are seen, the beds making a weU- marked feature in the hill face. To the south and east of this no rock is visible in situ tor a con- siderable distance, and the outcrop has to be inferred from the relative position of the Upper and Lower Lias, the whole Middle Lias being; mapped as one division. We will therefore take the outcrop of the Ironstone Series before we return to the country south of the great faults. Ironstone Series.— The outcrop of these beds in the escarpment may be easily followed by the feature they make jutting out below the soft Grey Shale. To the north-east of the area described the Main Seam of Ironstone is so thin as to be at present valueless, but following its course westward it thickens slowly, and forms a well marked low terrace at the scar above the head of Trow Beck. At the north-west point of Dromonby Hill the seam forms a considerable spread, the ground being covered with fragments of Ironstone. A trial drift was made here, but has fallen in. The base of the seam, which is a marly ironstone, caps the scar at the head of Tom Gill and the following section is seen : — Section at Tom Gill, Busby Moor. Ft. In. 6 4 Base of Main Seam of Ironstone. Dark ferruginous shale ... 60 Flaggy ferruginous siliceous nodules - 4 Ferruginous shale - - - - - 12 Hard, oolitic Ironstone (Avicula Seam) - - 1 3 Ferruginous shale, harder at base - 31 " Passing down the valleys at the head of Raisdale, the Ironstone Series has a well defined outcrop ; but rock exposures are rare, owin^^ to the thick covering of down wash, and no trial-holes have been made till the two streams unite. Just at this junction is a drift which has now fallen in, but from which Messrs. Tate and Blake give the following section of the Main Seam : — * Ft. In. __ . r Ironstone with dogger band at top and base -28 ™*^-^ Shale .... - I 5 beam ^ j^oug^jone with dogger band at top - - 1 9 Just south of this there is a fault which throws up the Iron- stone some distance to the south side, so that the Main Seam out- crops in the road close by High Crosslets, and the beds below have been exposed by the denudation. The outcrop on the south See Tate and Blake, The Yorkshire Lias, p. 140. MIDDLE LIAS — IKONSTONE SERIES. 23 side of Raisdale is quite clear, and in Harton Gill the following section may be seen : — Section of the Ironstone Series in Harton Gill, Baisdale. Ft. In. Thin indurated sandy band. Shale .... . 4 Indurated band . 6 Shale . I Sulphur band . - . . . I Ironstone dogger .... - 4 Shale . 1 (1 Ironstone* - - - 1 Shale* - - > Main Seam . 4 Ironstone, 2 feet Shale ...... 6 Ironstone, 2-Foot Seam - 9 Shale 6 Laminated sandy Ironstone {Cardium truncatum) 3 Shale, well-bedded - 10 Ironstone, Avicala Seam 9 Shale with few doggers 25 Total . 60 8 The hard, laminated, sandy, ironstone band, crowded with Car- dium truincatum, is very characteristic in this area. Its hardness often causes it to have a bare outcrop, and from it the position of the Main Seam can be fixed, even when the latter, as is often the case, is quite obscured by downwash. At the head of the small beck south of Breck House a trial-hole was made, which has since' fallen in. Here the bottom band of ironstone is 2 feet thick, of an oolitic and shelly character, while above are two other bands of ironstone, harder and more siliceous. The thickness of the whole with shale partings is about 6 feet. Returning once more to the main escarpment the feature alone marks the position of the Ironstone Series along the west face of Carlton Bank, and no trial holes occur till Swainby Mines, where the following section was proved : — Section at Ironstone Mines, Swainby. Ft. In. Hard sandy ferruginous bed Sulphur band (iron pyrites) Flaggy sandy bed - Sulphur band (iron pyrites) Ironstone - - 3 ft. 4 in - - 3 6 1 10 1 Shale Ironstone dogger Ironstone - , 10 „ -• „ 4 „ - 1 .. 6 „ -Main Seam - 6 Hard black shale . . - 2 3 Dogger band Softer dark shale . . - 3 4 Sandy hard shale Softer shale - : - : 7 4 Hard white ironstone - - 1 10 '■ Obscured by rubbish, 24 MIDDLE LIAS — IRONSTONE SERIES. Passing up Scugdale the outcrop of the Ironstone Series is faulted out for some little distance, but the ironstone was_ proved by two drifts further east, both of which showed the Main Seam to deteriorate in this direction. This is weU shown by the section at the head of the dale, which is as follows :^ Section of Ironstone Series at Head of Scugdale. Ft. In. Indurated shale band. Shale, soft and ferruginous - - - - Ironstone ------ Shale Ironstone - 1 ft. 8 in. 1 Shale - ,, 9 „ ^ nXain Seam - Ironstone 2 „ „ J Shale, soft and ferruginous - - - Small dogger band - - - - - Shale, ferruginous - - - Ironstone, blue oolitic, and very fossiliferous, 2-foot Seam. ------ Soft shale - - - Laminated sandy ironstone - - - Soft ferruginous shale - - - Small dogger band - - - - - Shale - - - - Oolitic white Ironstone, Avicula, Pecten, Src, Avicnla Seam - - - - - Shale, rather sandy ----- Ironstone, with erect Myacites Shale Doggers ------ Hard sandy shale - - - Ferruginous shale Though the position of these beds may be easily followed on the south side of Scugdale there are no clear outcrops nor trial holes, and it is not till Limekiln Bank is reached that the beds are again seen in situ. The Main Seam has been worked by drifts in different parts of this wood, but the ironstone is consider- ably thinner than in the present Swainby mines and was conse- quently abandoned. Below one of the drifts part of the beds beneath the seam are exposed, but not sufficiently clearly to be measured. Close by Scarth Nick the Ironstone Series are thrown down between two north and south faults, the eastern of which has a throw of more than 100 feet ; between these two faults the posi- tion of all the Lias beds is very difficult to fix. Just to the west of the second fault a small ditch shows — Ft. In. Shales. Ironstone, 2-Foot Seam - - - 1 Shales (about) - - - - 20 Ironstone, Avicnla Seam - 1 4 7 9 2 6 4 5 3 3 3 6 1 2 4 4 6 4 6 3 3 9 2 9 6 3 2 15 56 5 MIDDLE LIAS — IRONSTONE SERIES. 25 This is the last clear evidence of these seams about the Arnclilfe Woods. In the little outlier of Whorl Hill the jet pits show sufficiently clearly the position of the Ironstone Series, but there- are no good exposures. In Cod Beck near Thimbleby Lodge the following section is seen : — Ft. In. Hard shale band - - .-06 Shale with small doggers ... 40 Ironstone . - 2 ft. in. ] Ferruginous shale . 1 „ 4 „ i- Main Seam - 4 4 Ironstone - - 1 „ „ J Shale - - - < . . 10 Ironstone, full of small fossils, 2-foot Seam - 1 6 Shale - - - . - 20 White Ironstone, Avicnla Seam - - - 6 Shale . - - - . - 10 Thin, lenticular, ferruginous sandstone - - 1 Sandy shale - - - - - -'2 Thm sandstone .... 20 Shale - . . . - - 1 Thin sandstone . . . - - 2 Shale - - . . - - 6 Main bed of sandstone (Sandy Series). The occurrence of alternating flaggy sandstones and sandy shales in the lower part of the Ironstone Series is well seen here. As we proceed south the whole series becomes so arenaceous that it was found impracticable to separate these beds from the Sandy Series below. Along Thimbleby Bank all the upper beds of the Middle Lias are obscured by drift, the only section being in a small hollow to the S.E. of Nun House, where a thin seam of Ironstone is seen, probably the Avicula or lowest, about one foot in thickness. From this point the outcrop of the Middle Lia3 gradually sinks below the drift, except a doubtful exposure near Upsall Castle- which must be about the junction with the Sandy Series. It is not till Feliskirk is reached that the Ironstone Series is seen again. In the sharp bend of the road above the Church ironstone, which is evidently part of the Main Seam, is exposed, and the Grey Shales come on immediately above. A boring was put down on the top of the hill to prove the ironstone in this district and gave the following section* : — Oolitic iron-rock Upper Lias shale Nodular ironstone Soft shale - Nodular ironstone Shale Marlstone - Sandy shale - ■Si -a T3 Ft. In - 7 - 116 - 7 - 3 6 - 7 6 . 1 9 - 20 9 * Prof. J. Phillips, Quart. Joum. Geo!. See, vol. xiv., p. 9G, 1858. 19141. C 26 MIDDLE LIAS ^XBOySTOXE SEEIZS. The whole of the beds below the Ironstone nodiJar bands ^ven here belong to the Ironstone Series not to the bandy Series; the gradiial change of the fonner to an arenaceons deposit being referred to in describing the Thimbleby section. There are only two isolated exposures of the Ironstone benes near >e==^av, where the Middle Lias is let down by two tanlts between New Bed Marls. The first of these is close to Sessay Station, in the railway cutting at the '-Darlington 27' nule- post where gravelly ironstone has been dug out recen%, whole a few yards to the south the platy Jet Rock is seen. The other outcrop is at Barf HiU, the summit of which is covered by a similar gravelly ironstone. There must evidently be some thick- ness of the bed, but how much is not clear. South of Coxwold the Middle Lias forms a feature which may be followed along the hillside to Hnsthwaite, where the sand- stone is exposed in the village and makes a well-marked terrace. Beyond this the beds are depressed by a fault so that tiie next exposure is at the village of Thormanby, where there is a good section of the sandstone and limestone witii bands of fossils, principally Gardium truncatum, Acieula cygnijpes, and Pecten. cequivalvis, seen in the road dipping at an angle of 4 degrees to the south-east. West of Thormanby the iliddle Lias passes beneath the sands and alluvium of the flat, and from the general strike of the other beds probably curves rotmd by Boscar Grrange and Peep- O'-Dav, although nothing is seen of the bed in this r^ion ; the first section we get being at the stream a little beyond Swallows Xest, where marly sandstone is seen apparently strik- ing in this direction. South of this it spreads out towards Easingwold and forms a strong feature below Rising Sun where the sandstones are exposed, as also they are in the little guUy to the east ; and just above at the foot of Howe HiU there are firagments of oolitic ironstone from the upper part of this formation. At Halfway House and in the lane beyond beds of siliceous sandstone and ironstone are seen, the former containing Rliyn- chonella tetrahedra, Cardium truncatum, and Avicula inasquival- vis* ; east of this the Middle Lias is thrown up by a fault and forms an outlying mass surroimding the hiU at Crayke. At the side of Haverthwaites Beck a borehole was sank in search of coal apparently in these beds, but of this we coold obtain no account. Prof. Blake mentions having found Rhyn- chonella tetrahedra in fragments of oolitic ironstone from this boring.f * See ilemoirs of -the Geological SuTTev. Explanation cf Ouarter-Sheet 93 S.W^ p. 13. t Tate and Blake, The Yorkshire IJas, p. Ul'. UPPEE LIAS. Uppee Lias. The Upper Lias in the area here described consists in its npper part of rather soft dairk shale, containing a considerable quantity of finely disseminated pyrites. This character was formerly taken advantage of to bum the shale for the production of Alum, whence it is generally known as the Alnm Shale. The chief characteristic fossils in it are Ammonites communis. Am. bifrons, and Leda ovum. Below this the shale becomes harder, platy, and more bituminous, and is known as the Jet Rock, from the occur- rence in it of considerable quantities of jet. Ammonites of the type of Am. serpentiims and Am. gracilis and Inoceramus dnbivs are among the most typical of its fauna. Quite at the bottom of the Upper Lias is some 25 feet of soft shale, called the Grrey Shale from its characteristic colour. Fossils in this division are rather rare, but Am. annulatus is to be found in the nodules about the middle of the bed. From its soft character the Grey Shale generally forms a hollow, and sections of it rarely occur ; in fact, no really clear ones are known in this area. The Jet Kock has been mapped only in the northern part of the area. Its outcrop is rendered very clear by the continuous line ofdrifts covering, or rather fringing, the entire district; which have been worked in every accessible place, and a reference to them is unnecessary. There is, however, one point of special interest in connexion with these workings. The shale-tips show at a glance that fossils are much less common than on the coast about Whitby, Staithes, &C., while, on the other hand, there was a greater amount of jet obtained, and that in larger piecea In the western escarpment there are only a few isolated workings, the chief of which are near West Field House, north-west of Osmotlierley ; in the banks above Thimbleby Lodge : and north of Over SUton. There are also two very interesting outcrops of the Jet Rock, which give conclusive evidence of the existence of large faults. Of these the first is in CotdiflTe Wood, where the Jet Rock which has been mined lies close against the Gn/phcaa ineurva limestones of the Lower Lias. The second is in the railway cutting just south of Sessay Station, the platy shale being well seen even now, and the continuation of this outcrop under the drift was proved for some distance to the west by a large main drain driven to carry off" the water. A few hundred yards to the north the country is composed of New Red Marl under drift deposits, while the Jet Rock has been worked close to the village of Kilbnm, thus showing the presence of a very large fault. Sections of the upper part of the Alum Shale are fairly nume- rous, as the water oozing from the Oolites causes landslips, which form great scars in the shales below, several of which occur in the face of Dromonby Moor. In the nab-end of Carlton Bank there is an old alum quarry, in which many of the characteristic fossils may be found ,: but Qpmparing this with similar quarries on the coast, there is the c 2 28 UPPEK LIAS. same relative paucity of fossils as was noted in the case of the Jet Eock. The position of the outcrop of the Alum Shale in the northern, area, and, in fact, all along the escarpment, is too ckar to need a detailed description^ but there are a few interesting points to be noted. Of these the chief is the local eropion of the Upper Lias to a depth of nearly 100 at the south end of Cold Moor, in Eaisdale, The channel formed by this erosion passes through into Bjls- dale, and is filled up by the basement beds of the Oolite, showing a clear local unconformity. Another point of interest is the gradual thinning away of the Upper Lias, which, from being 200 feet thick at the north-east end of this area, diminishes to 160 feet at Swainby Mines, and to only 116 feet in the boring at Feliskirk ; still further south this thinning continues, the Upper Lias being about 100 feet thick in the neighbourhood of Coxwold, and not more than about 80 feet in the extreme south-east, near Crayke. The Alum Shale does not outcrop on the east side of the great faulted outlier of Borrowby, but on the. west it is frequently seen. South of Silton, in the main escarpment, the drift deposits creep up the hill, and in places entirely obscure the outcrop of the Upper Lias, the first clear exposure being on the hill side above Kepwick. In the pretty amphitheatre of Cowesby the drift rises well on to the Oolitic sandstone, but some sections are visible in the little pass between that village and Kirkby Knowle, as well as at intervals in the hill to the west. The Alum Shale is seen again about Knowle Hill ; in the bank just above the village of Feliskirk ; and in the sides of Mire .Beck, near Thirlby ; but there are not many exposures in this neigh- bourhood. On the north side of Hood Hill laminated shales are exposed just below the base of the Oolites, which must be near the lop of the formation, and at Osgodby Hall shales are also seen, which cannot be far from the base ; the upper portion of these shales is again seen round the Oolitic outlier at Stockings House, and in the road between here and Kilburn, but the best section about here is just west of Low Kilburn, where the Jet Shales have been worked, and show these beds dipping at rather a high angle slightly to the north of east. About 600 yards south of this point the beds are cut by the great Coxwold north fault, and by which they are shifted from 3 to 5 miles to the west ; so that their next outcrop is about Highfield House, the well of which is sunk into Upper Lias shale, which might be seen a few years since close to the well, and a little north-west of the house the shale has been turned up in draining. The Jet Shales, as mentioned above, are exposed in the railway cutting south of Sessay Station. South of Coxwold the Upper Lias comes in again at New- burgh Park, and may be easily followed along the escarpment to the south-west, where it forms the clayey slopes between the features made by the Middle Lias and the base of the Oolites. UPPER LIAS. 29 In the lane above Husthwaite these shales are exposed, and have been penetrated in a well at Gibbet Hill just above to a depth of 40 feet. By the Husthwaite fault these shales are depressed, so that they outcrop in the low ground north of Providence Hill, and crossing the neck of alluvium are seen in the railway cuttino- at Thormanby Hill, where they contain Inoceramus dubius and a small Ammonite, and afford about the best section in the district. South of this they curve round with the base of the Oolite to the south of Oulston, but are not exposed anywhere in this direction. At Howe Hill, near Hanover House ; at Easingwold ; and at Mount Pleasant there are outlying patches of thin clay, which i^^ exposed at all of these places. 30 CHAPTER VI. LOWER OOLITES. The principal area occupied by these rocks is that to the north of the Hambleton Hills, covering the wild district of Snilesworth and Whorlton Moors. Besides this there is a narrow belt flank- ing the western escarpment of these hills, which spreads out somewhat on Boltby Moor and about Coxwold, to the south of which it forms the western end of the Howardian Hills. The Lower Oolite consists of a great series of estuarine and freshwater strata composed of sandstone and shale, with thin intercalated marine beds, which divide the whole into certain definite horizons. The Dogger. — With the exception referred to in describing the Upper Lias that formation is conformably succeeded by this Es- tuarine Series. At the base of the whole is a calcareous ferru- ginous and siliceous bed, known as the Dogger or Top Bed, which according to the predominance of these three constituents is either a limestone, an ironstone, or a sandstone. Where first met with in this area at the north-east end of Vit- toria Plantation, it is a siliceous and ferruginous limestone some 6 feet thick. Towards the south it thickens rapidly to nearly 50 feet, and becomes a ferruginous echinital limestone, a species of Acrosalenia being extremely abundant. On the east side of the hill this limestone is lying in an eroded hollow of the Upper Lias, and at the extreme south end of Cold Moor a similar lime- stone is seen coming down to within a few feet of the Jet Rock. At the north end and west side of Vittoria Plantation a drift has been made into the Dogger, which fs here 20 feet thick and quite a different rock, being more like the same bed on the coast, espe- cially at the Peak, Robin Hood's Bay. It is so full of fossils as to be a marl, and rapidly disintegrates on exposure to the atmo- sphere. It contains vast numbers of little concretions, which contain a considerable proportion of phosphate of lime, and seem often water worn. The rock as a whole contains about 20 per cent, of iron. Owino- to the rapid disintegration of the bed it is difficult to determine the fossils in it, but among the more abundant are the following : — Ammonites. 2 species. Pleurotomaria calix. Eucyclus, sp. Lima electra? Modiola imhricata. Ostrea gregaria. Trigonia pulla. Terebratula trilineata. Acrosalenia, sp. Tkecosmilia, sp. Vermetus, sp. On the outlier of Dromonby Hill the Dogger is merely represented by a few bands of doggers or nodules, but on the little THE DOGGER. 31 outlier of Wath Hill to the south it is again a ferruginous lime- stone from 3 to 6 feet thick. In Raisdale it is also merely represented by nodules at the east end, but in the centre of the dale it is a ferruginous limestone from 3 to 8 feet thick, which character it maintains as far as the fault. To the north of this it quickly thins away, a little band only of the somewhatphospjiatic nodules representing it. Towards the north end of Carlton Moor it is too thin to be traced, and a few doggers may represent it in the alum quarry, as well as along the west side of the hill, and in the outlier of Whorl Hill where nothing is seen of this bed. A boring put down in a quarry over the entrance to Swainby Mine showed no distinct representative of the bed, and none can be seen (though it may exist in places) till the head of Thackdale is reached, where it is 3 feet thick, being shaly in the middle and very fossiliferous at base. It would appear to maintain much the same character and appearance round the head of Scugdale, for at Bank Crag it is 4 feet ,thick, while south of this, and at Blue Scar it is 5 feet. The section at the latter place is — Ft. In. Sandstone - - - - - -15 Shale - , - - - - -2,0 Dogger, impure ferruginous limestone - -50 This Shale, which is very similar to the Alum Shale, generally succeeds above the Dogger, where the latter is a calcareous bed. In Harfa Bank there is no good representative of this part of the Lower Oolite, and it is. not till approaching Limekiln Wood that exposur-es of the Dogger are again seen. Here it is an impure fossiliferous limestone,, or rather a hard shelly marl containing a good deal of iron. It has been burnt for lime in former days, but had a tendency^to run to a slag if jiot carefully watched. In the long scar about the centre of the- wood -the following section is seen : — Sections in Limekiln Wood, Whorlton Moor. Thin sandstone, well-bedded Shale (like Alum Shale), with dog:gers Rather pure ironstone - - - Hard ferruginous marl . . - Towards the west end of the wood the section consists of thin sandstone and shnle as above, succeeded by — Ironstone, very hard and fossiliferous Myacites sp Pholadomya Smmanni, Ammonites sp., Selemnites, Terebratula irilineata and many other fossilS; difficult to extract whole - Very hard marl, siUceous at base 6 Ft. - 10 12 - 1 - 25 In. consists of Ft. In. - 1 - 4 3 9 Ft. In, 50 15 2 15 .0 2 5 4 32 THE DOGGER. Between the faults at Scarth Nick nothing is seen of the Dogger, but it is exposed again along the north-west corner of the great escarpment, where it is about 4 feet thick. Another fault brings this bed still further up the escarpment to Beacon Scar, where the following fine section is exposed : — Massive soft sandstone .... Carbonaceous shale with sandy partings Flaggy sandstone ..... Shale, like Alum Shale - . : . Thin, carbonaceous, gannister bed ... Shale full of nodules, contains Ammonites in lower part ...... Calcareous ferruginous bed with shaly parting Alum Shale. Along Mount Grace Bank over Osmotherley, and for a consider- able distance up the valley, there is no Dogger seen, and it certainly cannot be thick ; for, above the west side of Osmotherley High Mill Oolite Sandstone and Alum Shale are seen within a few feet of one another. Nothing is seen of the Dogger east of Osmotherley owing to downwash and -talus, but near the head of Oak Dale is an opening marked as " old limestone quarry " on the Six-inch Map, which may have been" an old working of this bed, In^the old Alum Works near Thimbleby Lodge the Dogger is about 18 inches thick, presenting the same ferruginous calcareous character ; but in a trial-hole at the scar over Thimbleby it con- sists merely of a few nodules in shale and in the small hollows about Over Silton it is not seen anywhere. Near Kepwick at a trial-hole in Atley bank the following section may be seen : — Ferruginous sandstone Shaly sandstone ... Grey shale - - . . g, TThin band of ironstone M Shale 2 01" Q < Hard ferruginous hmestone - .56>116 •g' Shale . - - - . 1 6 [ Eh (_Ferruginous limestone - - - 2 OJ In the interior of the Moorland there are several outcrops of the Dogger, the finest of which is in the upper branch of the Eye close under Snilesworth Shooting Lodge. A ferruginous lime- stone about 5 feet thick, passing at times into a calcareous ironstone is seen in the bed of the stream ; under which it sinks for about 50 yards, and then rises again some few feet above the river, havino- Alum Shale beneath it. A similar outcrop is seen in Ams GiU to the east, the Dogger being here from 2 feet to 3 feet 6 inches thick. The junction of the Lias and Oolite is seen again at High Farm, where there is a small inlier of the ^lupi Shale, but the calcareous bed is absent. Ft. In, B ■■ 6 . 6 - 2 6 Ft. In. 61 THE DOGGER. 33 About the great faulted outlier there is no visible outcrop of the Dogger on the east side, but on the west it is comparatively clear. Close by Beacon Hill at the north end some 3 or 4 feet of ferru- ginous limestone is seen resting on Alum Shale, and from this point southward a similar bed maj^^ be found at intervals, slowly thickening in this direction, till at the hollow where the road crosses the hill at Cotcliffe Bank the Dogger is a ferruginous sandy marl with shaly partings some 20 feet thick. Its outcrop con- tinues clear till it begins to turn south-east, when the drift creeps up the hill and obscures it. Around the little Oolite hill at Knayton the Dogger is similarly hidden. Continuing along the main escarpment in the neighbourhood of Cowesby the drift reaches just up to the base of the Oolites and the Dogger is not seen, but an old slag heap not far from the Hall gives reason to suppose it was once worked there to a small extent. Round the outlier north-west of Kirkby Knowle it out- crops in several places, particularly in Low Wood and near New Buildings, where it is a ferruginous limestone about 4 feet thick. At Knowle Hill and in the main escarpment close by it is well seen, a trial-hole in the latter place showing it to be a calcareous ironstone some 5 or 6 feet thick. From this point past West Acre Lodge to close by Boltby the outcrop is very clear, an adit close by the village showing that it retains much the same character. On all the outliers about here the Dogger may be seen in some part of them ; about Feliskirk HiU it is a ferruginous limestone 6 to 8 feet thick, and has been worked as a limestone to a small extent on the north-west face of the hill. North and east of Boltby the gravel that is so abundant about here obscures the outcrop, but it reappears north of Tang Hall having the same character, an adit having been made into it. Further south the position of the bed is fairly clear. At Cleaves Quarries, where it has been largely worked and burnt for lime, it has a thickness of over 20 feet, as will be seen from the following details : — Section, at Cleaves Bank Quarry. Massive soft sandstone, verjr ferruginous at base Blue clay and soft beds with oalcareo-argillaceous balls Massive false-bedded siliceous limestone Thin band with Ostrea, Pentacrinus, and scattered pebbles, very pebbly at base . - - Oolitic limestone (base not seen) ... In the next quarry at the side of the Thirsk road the shaly band between the sandstone and the limestone becomes thicker, there being over 20 feet of it; the limestone also becomes more pebbly in this direction and beyond Hood Grange appears to thin out, or is only represented by a ferruginous sandstone. The out- crop here shows how irregular this bed is, for whereas on the north side of the valley at Hood Grange it has a considerable Ft. In. 30 4 10 1 6 6 6 34 THE DOGGEE. thickness, on the south side below Hood Hill, a distance of only 500 yards, it is not present, or is so thin as not to be traceable. In the road between High and Low Kilburn there are some shales with thin ironstone nodules which may represent this bed, but it is too thin to be mapped anywhere in this area. South of the Coxwold faults the Dogger comes on again very strong; it is here a massive ferruginous glance limestone and forms the fine feature of Beacon Banks, south-east of Husthwaite. Just south of this village it is thrown down by a fault, and out- crops in lower ground being well exposed in a quarry below Highthorne, and also at Providence Hill where it passes beneath the alluvium. South of these hills the Dogger again appears to have thinned out, for although the base of the Oolites makes a fairly good feature along part of its course this bed is not seen, nor is it of sufficient importance to map till we reach the neigh- bourhood of Terrington, a distance of nearly 10 miles.* Lower and Middle Estuarine Series with Marine Bands. — Between the Dogger and the Grey Limestone Series along the north-west escarpment of the Oolites there is a series of massive and shaly sandstones with a little shale, which have a thickness of about 250 feet. These measures, which about here are much more sandy than they are in the next map, contain in the northern part of their outcrop one, and in the southern two, distinct marine beds. Of these two the lower consists of thin flags with shale below con- taining one or more bands of fossUiferous ironstone, and is known as the EUer Beck Bed, but further south these strata become more calcareous and a true limestone sets in, which has been mapped under the name of the Hydraulic Limestone. The EUer Beck Bed and Hydraulic Limestone. — As the Eller Beck Bed is rather thin it is not easily found, unless the strata are cut through by stream sections, or when this bed occurs close under the bearing rock of a scar, as often happens in the great escarpment, where it has usually a thick ferruginous sandstone above. In the long outlier of Cold Moor this'brown sandstone is well seen, but there are no sections below, so that it was impossible to find the marine bed. On the roughly triangular area of Drom- onby Hill the brown sandstone caps the scar, in the face of which the fossUiferous ironstone is seen, being from a few inches to a foot in thickness; the depth to the Dogger below being about 100 feet At the north end of Carlton Bank it is not seen, probably owing to the accumulation of debris from tJie brown sandstone » Memoirs of the Geological Surrey. Explanation of Quarter-Sheet, 96 S.E p. 6. ESTTTAEINE SERIES. 35 but passing south-east, a section is exposed in the road leading off the Moor to Staindale Farm, which is as follows : — Ft. In. Carbonaceous shale - - - - - ,9 Flaggy sandstone - - - - - 6 Shale 6 Ironstone with fossils - - - - 6 From this point it can only be followed for a short distance. On the south side of Raisdale and on Bilsdale West Moor the outcrop is fairly clear, fossiliferous ironstone fragments being seen in the Bridle Road leading down to Chop Gate and again further south in the scar called " The Olough " overlooking Bilsdale. The small section of shale with little ironstone nodules above the sandstone quarry at the extreme north-west point of the main escarpment probably represents the EUer Beck Bed, but no men- tion of it is made in the following boring, put down some little distance to the south : — Boring on Osmotherky Moor.* Freestone - Blue plate - Red grit Soft blue plate Coal Freestone - Ft. In. 30 12 6 2 6 120 Total - . 170 6 After sinking to this depth they bored 150 feet further, and passed through many bands of sandstone and shale, and seem to have left olf in some soft white freestone, but as they kept no good account the boring is doubtful. If they commenced just below the Grey Limestone Series, it would give the depth of the well-known Moor Coal as a little more than 50 feet below that series,and according to this boring there should be some 320 (!) feet of these estuarine beds, but as the whole is seen in the face of the escarpment to be clearly not more than 270 feet there must have been some mistake in the boring account, or else this coal does not represent the Moor coal at all, but is the thin upper seam, which was also found in the country to the south at Birdforth. South of Osmotherley for a considerable distance the only evidence of the EUer Beck Bed is some fine-grained fossiliferous flags seen close by Hunter's Hill in the hollow north-east of Nether Silton. * Winch ; Trans. Geol. See, vol. v., p. 551, &o. 36 .ESTDARINE SERIES. On Snilesworth Moor there are some very interesting inliers of the Eller Beck Bed. The first of these is in the uppermost reaches of the Rye, near Skelbeast Crag, a little below the coal workings on Coal Rijige. At the,, point where the stream divides a fine-grained .flaggy- sandstone may he seen having a few casts of fossils near the base ," this is succeeded by shale and though not seen the thin' ironsfone seam is "probably at the base of this. Following the outcrop round into Proddale Beck, the ironstone is 2 feet thick and contains a considerable number of fossils ; further down on the east side of the otream there is no evidence of the exact outcrop, but on the west side of the Rye its position may be fairly well made out by the flaggy sandstone which makes a small but continuous feature. Passing up for a short distance into Wheat Beck the ironstone is seen again in the stream, being 1 foot 6 inches thick, and on the south bank may be followed till it sinks beneath the Rye at Burfat House, where the ironstone is some- what thinner. Along the south-east side of Arns Gill the fragments of ironstone seen at intervals mark the position of the Eller Beck Bed for a considerable distance up the dale, and drifts have been made into it. Nearly a mile east of this, in Blow Gill, is another inlier of the Eller Beck Bed. - It consists -of thin flaggy sandstone with about 8 feet of shale below. Beneath the shale is a seam of light coloured, somewhat oolitic ifonstofle, containing a great number of fossils, of which PJioladojnya Murchisoni is by far the most abundant. The section is — . Ft. In. Flagpty sandstone. ' Shale - - ... 8 Ironstone very fossiliferous - - - - 2 6 Near the lower end of the stream a third inlier of this bed is exposed, and just below Blow Gill Farm the following section was measured : — Ft. In. Sandstone. Shale - - - - - - - 5 Thin ironstone - - •■ - -04 Shale - - - - - - -30 Ironstone with fossils - - - . - 6 Shale. There appears to be four or more thin ironstone seams here, but they are not all exposed in one section. At Coneygarth Hill on the outlier north-west of Kirkby Knowle this seam of ironstone is sufficiently thick to make a marked feature and strew the hillside with its fragments, but as soon as ESTtJARINE SERIES. S7 the hill becomes steeper and the Oolite sandstones have a narrower outcrop this bed is again lost sight of. A flaggy sandstone containing fossils, which is seen in two places in the main escarpment opposite this hill, is probably the upper part of the Eller Beck Bed, but from this point there is no evidence till Skipton Hill near Thirlby is reached. Here the bed has considerably altered In character, and a thin limestone sets in, which gradually becomes thicker and more important towards the south, while the ironstone which accom- panies it is less noticeable. This bed which we now describe under the name of the Hydraulic Limestone is a hard grey argillaceous limestone never more than a few feet in thickness, but which, from the fragments of it weathering to a whitish colour, is very conspicuous when it comes to the surface. This rock first becomes noticeable below Whitestone Cliff where it forms an outlier round Skipton Hill and may be followed along the escarpment below Gormire Lake. To the west and south of Hood Hill the bed is exposed at several places, having apparently been worked below Penfitt Wood ; east of this it is seen at Acre House and between High Kilburn and Kilburn Thicket, but the outcrop in this direction is rather obscure. In the Coxwold area there is a small outcrop of this bed close to the southern fault, fragments of the rock being seen in the beck below Angram Grange. South of this fault the Hydraulic Limestone is seen just south of Garbut Gill, but the outcrop along the southern escarpment and also on the faulted outlier south of Husthwaite is not good, although fragments of the rock are seen at a few places. Between Garbut Gill and Newburgh the outcrop shown on the map is hypothetical, the rock not having been observed between these points. Moor Coals. — In the Estuarine Series there are one or more seams of coal which have been worked at several places, but, unfortunately, little appears to be now remembered about them. In the inlier of these beds to the north of Hawnby the coal, which is 10 inches thick, outcrops about 50 feet, belov/ the Grey Limestone Series on either side of Ladhill Beck. There are also several old coal pits along Stonymoor Sike, the northern branch of the Rye near Coal Ridge ; an adit has been made to the coal here, and fragments of it are seen in the road going to Skelbeast Crag. It again seems to have been met with, as we have men- tioned in the boring on Osmotherley Moor and in the hollow to the north-east of Nether Silton, there being several old adits in the lower part of Swinestone Cliff Plantation. Some old coal pits may be observed in the bank east of Kepwick, and there are indi- cations of a coaly seam at one or two places along the escarpment to the south. South of the Hambleton Hills this coal has been worked on the outlier above Kilburn ; but the principal workings were between the faults near Burtree House north of Birdforth, 38 ESTUAEINE SERIES. at Coxwold, and in Newburgh Park; at the latter place Mi. Winch gives the following section : — Section of the Engine pit in Newbury Park Colliery, the seat of the late Lord Falconherg, near the village of Coocwold, Yorkshire. Soil - - - - Blue metal - - Soft blue metal - . - Strong grey metal with catheads Coarse strong grey post Coal . . - - . Total The seam of coal is of irregular thickness, seldom under 10 or above 16 inches. It dips to the east 2 or 3 inches per yard. The coal is of an inferior quality. At Birdforth, where the coal was worked about the year 1760, there were two seams, the lower of which is said to have been from 3 to 4 feet thick, and at about from 25 to 30 yards below the surface, but dipping rapidly in a north-west (east?) direction ; it could only be found over an area of about a quarter of a mile. Millepore Bed. — Forming a belt roimd the smnmit of the outlier of Kirkby Knowle is a curious bed of Sandstone, or white Grit, cemented together by crystalline carbonate of lime. It seems as if the lime in the stone had been entirely crystallised out by the slow action of solution and redeposition. The quarries in it show the extremely false-bedded character of the rock, and strikingly remind one of the Millepore Bed as seen on the coast. From its position in the hill above the EUer Beck Bed and below the Gfrey Limestone there can be no doubt that this does represent that bed ; and it is certainly the same as the Oolite of Whitwell, which latter has been proved upon palseontological evidence to be the equivalent of the Millepore Bed.* At the nab end called Wind Egg, to the south-east of Kirkby Knowle, a similar bed may be seen, but in this case there are little shell-masses at intervals, in small wedges, mixed up with frag- ments of Encrinites, &c. This curious rock is continuous only as far as the south point of the hill near Westow Hall. With the exception of these isolated outcrops the Millepore Bed first becomes traceable as a separate horizon on the outlier of Hood Hill, where it is seen on the south side of that hill at High Ground Barns. The next exposure is in the lane above High Kilburn, where this rock forms the southern end of that outlier, being faulted against the Grey Limestone, and for which it might be easily mistaken. The third and last exposure north of the * See Memoirs of the Geological Survey. Explanation of Quarter- Sheet, 93 N.B. p. 14. Ft. In. 8 8 1 3 4 6 2 6 MILLEPOKE BED. 39 Coxwold faults is on the three outlying patches at Scencliif Grange. The rock is here somewhat thicker and better exposed than it has been further north and contains the characteristic Cricopora straminea, which we have found at one or two places. In the Ooxwold area the Millepore Bed is not exposed, being hidden by drift, and the position of the outcrop is assumed between the other beds. South of these faults it comes on again, and is seen above Newburgh Grange. At Garbut Gill the out- crop is shifted by the fault, and being exposed in several quarries to the south forms a good feature, which may be traced along the escarpment to Oulston. In the quarry below the village here this limestone is worked and the following section was measured : — Section in Oulston Quarry. Shaly beds --.--. Siliceous sandstone ----- Shale Hard oolitic stone in two beds ... Softer and more shaly beds - - Hard blue limestone partly oolitic on top, weathers brown, base nbt seen - - - - 6 Sandstone below. The limestone, contains Ceromya Bajociana, Isocardia cordata, and other fossils similar to those from ^he Oolite at Whitwel)., In the faulted ground to the south of Husthwaite there are two outlying patches of this rock capping the hill at Highthorne and Sand Hill. The Scarborough or Grey Limestone Series. — These beds, although mapped as one series, are capable of subdivision into three groups, each of which generally makes a distinct feature along the line of outcrop. At the base there is an alternating series of siliceous and calcareous beds with shales and thin sandy bands which are well seen in the road below Novey House on the west side of Ladhill Beck, where is the following section : — Ft. In. Shales with fossils. Grit. Hard, sandy, siliceous beds - - - - 3 Sandy shales - - - - - -50 Siliceous arid calcareous beds - - - - 4 Shales. Above this comes a considerable thickness of porous grit con- taining the casts of Avicula braamburiensis and other fossils in great abundance. This is the principal rock of the series, and being harder than either the beds above or below forms a good feature which spreads over a large area of the moorlands to the north. Lastly, above the grit is a band of shale forming a bank of wet ground beneath the Moor Grit above. The total 46 GKEY LIMESTONE SERIES. thickness of these beds is about 70 feet, but there is no clear section in which all the beds can be measured. The blue flaggy limestone at the base of the series sometimes makes a clear outcrop, the ground being covered by fragments of it ; as is well seen at the head of Ladhill Beck along the northern outcrop, where these beds must be very thick, and at the south end of Over Silton Moor. At the northern end of the outcrop on Osmotherley Moor, just below Low Mossy Grain, a drift was put in to try and find the limestone ; and the bottom bed was met with, being full of GervilUa and Pecten, but only a foot thick. The fossHiferous grit, Tvhich contains casts of Encrinites in great numbers, makes a series of little steps up the hill side. At the head of Oak Dale, near Moor House, wbere the rock is quarried and partly mined for road-metal, a drift has been made into the basement limestone, which is here very hard, of a blue colour, and about 6 feet thick. It is quite evident from the above that going north the calcarelous beds almost disappear in this area, and at the same time that the grit becomes thicker and coarser. This last fact is well brought out by the great detached mass of fossiliferous grit on the watershed between Scugdale and Eaisdale; which is at least 40 feet thick, and contains quarts grains of the size of a pea, being by far the coarsest form in which this bed is known. These grits are very porous, and from their base give out powerful springs, some fine examples of which may be seen at the sources of the Cod Beck above Osmotherley, and again at Newfield House on Snilesworth Moor. At this last place the calcareous beds were worKed for lime or cement, and some time ago in pulling down an old wall cemented with this lime, the bricks had to be broken to pieces before the lime showed any signs of giving way. In the next map, 96 N.E., the outcrop of these beds is well seen in Bilsdale, and may be traced from thence along the west side to the moors above Wether Cote, where they enter this district, and the blue sandy limestones at the base with GervilUa acuta and Avicula braamburiensis are exposed .in the road at the side of the enclosures. Above this the gritty portion of the series spreads out over the summit of the moor and forms a band completely encircling the higher part of Ladhill Beck, so that the Estuarine beds exposed in this valley form an inlier. On these moors the limestone has been worked and burnt for lime at one or two places. Near Hazel House there are some ourious hollows called " Hell Holes," which have evidently been formed in the grit by the calcareous beds below being dissolved out. Both in Ladhill Beck and the Kiver Rye the Grey Limestone Series is well exposed, and west of the latter forms a good feature, which may be easily traced by Brewster Hill and Gate Cote to Dale Head, where it turns round the head of the vaUey by Stephen Thwaites and Newfield House. North of this these beds cross the higher waters of the Rye and may be traced across GEEY LIMESTONE SERIES. 41 the moors to the trigonometrical station 1,184 on Whorlton Moor. The outcrop now turns round to the west, and although broken by several small faults forms a considerable spread on Whorlton Moor. East of Osmotherley the Grey Limestone follows the brow of the hill for some distance, running out in a broad tongue above Over Silton, where the limestone beds at the base have been worked. In Swinestone Cliff the three divisions become very distinct, and the fossiliferous grit, which is very ferruginous in its upper part, forms a bold crag in the plantation below the house. . In the neighbourhood of Kepwick the Grey Limestone forms the conspicuous promontories above Nab House and above Atlay Bank, being well exposed at these places, and also where the road crosses the outcrop east of the village at Eag Eobin Turn. Above Oowesby Wood these beds follow the brow of the hill for some distance, and at Brockholes, near Kirkby Knowle, where a large landslip has taken place, the following section was measured : — Section at Brockholes, Kirkby Knowle. Ft. In. Grit, with a siliceous fossiliferous bed near the centre IG Shales passing up into sandstone - - - 4 Rubbly calcareous beds full of fossils - - 6 Siliceous sandstone with fossils (Ostrea) - - 8 Argillaceous limestone - - - - 6 Sandstone - - - - - -06 Hard bluish grey limestone - - - - 1 Shales. Massive sandstone. Shales. Massive sandstone, with shales and a little jet in the centre. East of Kirkby Knowle the Grey Limestone winds round the hill forming the two projecting nabs above Westow Hall and Boltby, and, turning up the valley of the Lunshaw Beck, is exposed in the bed of that stream for nearly a mile. Below Lunshaw House there are some trial-holes into the lower part of the limestone, but for whatever purpose these were made, it seems to have been a failure. « On the east side of Lunshaw Beck the outcrop is entirely hidden for some distance by large landslips of Calcareous Grit and other rocks which have come down from above, and it is only on the projecting points, as below Hesketh Grange, Little Moor, and near Garbutt Wood that we get sections in the rock. South of Whitestone Cliff the outcrop is again hidden for some considerable distance, and it is not until the beds turn round to the east below Roulston Scar that they are again exposed. The Grey Limestone now becomes more easy to trace, and may be fol- lowed along the hillside to Snever Wood, where it forms a conspicu- ous bank in the lower part of that wood. The outcrop here crosses the beck, and after a somewhat obscure course round the hill to o 19141. D 42 GREY LIMESTONE SERIES. the west of Oldstead, is again well exposed in the neighbourhood of Oldstead Grange, where it makes the low feature on the east side of the old fish pond. At the southern end of this pond the Grey Limestone meets the large east and west fault of the Cox- wold valley, and is thrown down some hundreds of feet, the out- crop being shifted nearly four miles to the west. Between Byland Abbey and Ampleforth there is an inlying outcrop of these beds which skirts rotmd the hill at the back of Wass village ; the bed which is not seen in this map is exposed at the corner of Burtis and Low Woods in Quarter-Sheet 96 S.E., just east of which it again meets the large fault. On the southern side of the north Coxwold fault the Grey Limestone is first seen at Thirkleby Barf, where it has been ex- tensively quarried for road-metal. The beds here, which are harder and more massive than is usually the case, are divisable into two portions, the lower part consisting of hard beds of blue fossiliferous limestone, while above this are soft massive sandstones with casts of fossils, which become more flaggy in the upper part. These beds, -which at Thirkleby Barf dip about 15 degrees to the north-east, to the east of Burtree House curve round and above Barf Hill, dip at about the same angle slightly to the west o£ north, so that the outcrop is. extended in an easterly direction by Wildon Hill to Coxwold ; at all of these places the rock is exposed in old quarries, but is not seen along the intermediate ground, probably owing to the thick covering of Boulder Clay lying in the hoUows bet;ween. . In the beet to the south of the railway at Coxwold these beds are seen dipping to the south-east at an angle of 10 degrees, being bent over towards the second large fault by which they are thrown up so as to outcrop only in the south-east corner of Newburgh Park, as outliers at The Mount and Park House in the next map. Besides the main outcrop of the Grey Limestone there are several outliers. These occiu" as patches on the moors to the north, and fringing some of the hills in the neighbourhood of Kirkby Knowle and Kilburn to the south, the most northerly being that on Whorlton Moor, where the beds are depressed by small faults, and a patch of the fossiliferous grit has been pre- served, forming a line of crags on its south side. In the north- west corner of thetnoors there are also some small patches of this rock which are much intersected by small faulta, and to which, to a great extent, they owe their preservation. Further south on Snilesworth Moor there are four of these outliers between the several tributaries of the Rye which, from the strong character of the grit and the absence of drift, are very distinct. In the southern part of the district at Hood Hill, near Kilburn, and on the hill behind that village, there are also some outliers of the Grey Limestone ; at the last of these places the outcrop is rather obscure, but a small portion of the limestone is seen on the northern side of the hill ; at the southern end of the hill the Grey Limestone is thrown out by a fault, so that the limestone UPPER ESTUAEINE SERIES. 43 which is there seen apparently on the same line of strike really belongs to the MiUepore bed. South of the great Coxwold faults the only outcrop of this bed is the outlier at The Mount to the east of Oulston. Upper Estuarine Series. — These beds consist principally of shale, with thin irregular beds of sandstone, and at tile base a thick bed of massive sandstone — the " Moor Grit." They have a total thickness of about 200 feet, but in many cases there does not seem to be so much as this, especially to the north-west, where there is not much more than 100 feet of these beds. The upper portion of this series, as a rule, makes wet clayey slopes, at the base of which the Moor Grit forms a distinct feature, often cover- ing a considerable area of moorland. The outcrop of the Moor Grit follows that of the Grey Limestone so closely, that it fre- quently merely forms the upper part of that feature, and the description of one does for that of the other ; but in a few cases, as on Bilsdale West Moor, Hawnby Moor, and over part of Snilesworth Moor, where this grit is partly of a gannister nature, it runs out in broad tongues, in a similar manner to the fossi- liferous grit below, the ground being covered with large white siliceous blocks. The shaly portion of this series • does not generally afford good sections, their outcrop, which is principally below the steep escarp- ment of the Middle Oolites, being usually covered by the debris from that formation. The beds are, however, seen in some of the deeper valleys about Hawnby, and also on Osmotherley and Boltby Moors, where they run out from the overlying beds, and form their largest spreads. Cornbrash, — The outcrop of the Cornbrash in this district is very uncertain, as the bed has not been anywhere observed, except in Northwoods Slack, above Boltby Moor, where is a little grey sandy limestone with Ostrea, which may represent this formation. On the strength of this the outcrop might be continued from the east and north as far as this point, there being a good line between the Estuarine Shales and the sandstone of the Kellaways B,ock, although there are no sections exactly on this horizon. South of Boltby Moor, however, the base of the Middle Oolites is not so strongly marked, and, in fact, coming as it does in the midst of clays, it is impossible to say exactly where it should be drawn. There is certainly no evidence for carrying on the outcrop of this rock, and in the Howardian HiUs, as we have noticed in the Expla- nation of Quarter-Sheet 96 S.E., it probably does not exist. D 2 44 CHAPTER VII. MIDDLE AND UPPER OOLITES. Middle Oolites. Kellaways Rock. — The Kellaways Rock in this district under- goes a considerable change both in character and position in its passage from the north to the south. In the northern part of the Hambletou Hills it is a thick-bedded massive sandstone, partly siliceous and partly sandy, with a ferruginous band towards the top, similar to what the rock has been further to the east, and having a thickness of about 60 feet ; but in the southern part of these hUls this rock, which is a soft red grit crowded with Gryphaa and Belemnites, comes in immediately below the Calcareous Grit, the lower part of the Kellaways Rock splitting up into shaly beds as if the clayey part of the Oxfordian series were setting in at the base instead of above this rock. As we trace this formation further to the east towards the Howardian Hills the normal posi- tion of the beds comes on again, so that it would appear that it is only to the extreme south-west that this peculiarity occurs. The outcrop of the Kellaways Rock is continued from the next Map along the south bank of the Rye by Ristbrow and Dale Town ; it also runs up the valley north of Old Byland, being exposed at Cadale Mill and other places. West of Hawnby about Coum Hill and Arden Hall the rock is not so well seen being generally covered by landslips and the debris of the rocks above, but it is well exposed around the large outliers of Easterside and Hawnby Hill, especially towards their northern and southern ends. Around the flanks of Black Hambleton the Kellaways Rock usually forms a good feature ; it is easily followed as far as Kepwick, where the talus from the hill above again obscures everything. On Boltby Moor above Cowesby the Kellaways Rock also forms a strong feature and running out in a long tongue is well exposed in several road-sections on that moor. South of this the outcrop is not seen till we get to Hesketh Grange, where it is exposed in the road ; there is also a good section below Boltby Scar of red ferruginous sandstone with Am. modiolaris, Belemnites, Ostrea, &c. Below Whitestone Cliff, where there is a fine scar exposing these beds, the lower part of the Kellaways Rock is seen to be getting much more shaly, and a bed of clay comes in which we have mapped with the Oxford Clay, and not with the Lower Oolites, as it seems to occupy the same horizon as the sandstones further north which here appear to be gradually dying out: in the next section we obtain the rock presents quite a different phase. KELLAAVATS EOCK. 45 At the base of Roulston Sear there is a peculiar red ferruginous rock crowded with Gryphaa subloba and Belemnites, which although it lies immediately below the Calcareous Grit, must from the fossils it contains belong to the Kellaways Rock. It has a thickness of nearly 50 feet, as will be seen from the followino- section measured at the base of the scar : — " Section below Roulston Scar. Ft. In, 5 20 9 8 Vertical cliff of lower calcareous grit, consisting of alternations of hard and soft sandstones with lines of curious forms, resembling fucoids and sponges, much eaten out by eyposure to the weather, which has given the beds a very rough and irregular appearance. Soft sandstone, very full of Belemnites, contains also Gryphaa, Avicula inmquivahis, and Avicula ovalis 1 6 Sandstone beds with lines of fossils Gryphaa subloba, Belemnites Owenii, Placunopms - . Massive sandstone with Gryphaa Harder bed . - . . , Yellow sandy rook jointed becoming softer below Pedp beloyir hidden by talus. Total Kellaways Rock seen - . 43 6 Following round the outcrop to the east the rook is well seen in the several gullies coming down from the moor, especially in the third one known as Ravens Gill where the section is — Section in Ravens Gill. Ft. In. Limestone - - - - - - 30 Red rock containing Holectypus depressus and great quantities of Belemnites, Ostrea, SfC. - - 1 5 Massive yellow sandstone - . - - 20 Total Kellaways Rock - - 36 ft. The base is not seen, but it cannot be far below, as wet clayey ground very soon comes on. The limestone belongs to the mea- sures above, as will be mentioned further on. Beyond this the rock is not again exposed, and there is no evi- dence to say whether it really exists or not between here and its outcrop in the Howardian HUls to the south of Hovingham. The outcrop has, however, been carried on ; as in Snever Wood and beyond, there is a sandy bank below shales, which seem to indicate that the Kellaways Rock is coming on again in its normal cha- racter below the Oxford Clay. Besides the large outliers of Kellaways Rock near Hawnby, there is an outlying patch on Osmotherley Moor to the north of Black Hambleton, the rock here which is very fossiliferous in its lower part is divided into two portions by a shaly band ; this is ^very often the case along its niost northerly outcrop as we noticed 46 KBLLAWATS EOCK. near Levisham, Saltergate, and Langdale End* The only other outcrop of the Kellaways Rock, if we except that between the faults at Coxwold, of which nothing is known, is on Hood MiJl ; here, immediately below the Calcareous Grit, which caps the hill, there is a small exposure of sandstone with Belemmtes which much resembles the rock seen at the base of Roulston Scar just opposite, and seems to occupy a similar position. Oxford Clay — The Oxford Clay, which in the northern part of this district consists of sandy shales, and has a thickness of about 50 feet, gradually thins out to the south ; so that below Whitestone Cliff it is only 30 feet thick, and between there and Roulston Scar disappears altogether. At Whitestone CM, as we have noticed above, the lower part of the KeUaways Rock appears to be splitting up and turning into shales, and a lower bed of clay occurs, so that virtually in the extreme south-west the Oxford Clay is below the KeUaways Rock ; as we trace the beds, however, eastwards towards Wass the clay comes on again below the Cal- careous Grit, and if we foUow the beds further east to the Howardian Hills, we find the Kellaways Rock below these shales in its normal position. The outcrop of the Oxford Clay follows that of the KeUa- ways Rock round the Hambleton Hills forming in general a band of wetter ground between that rock and the Calcareous Grit above ; but this is not always the case, as the great quantity of talus and the numerous landslips from the grit and limestone have frequently completely concealed the clays and entirely altered the character of the ground. These shales may, however, be seen on the hiUside to the south of Hawnby, and there are long tongues running up the vaUeys on either side of Old Byland. Near Ardeh Hall they have been worked, and there are sections at a few places round the flanks of Black Hambleton, but they are not of much interest. The best section is that below Whitestone Cliff, where there is a clear scar showing 30 feet of these shales between the Calcareous Grit and the Kellaways Rock, Avhich latter is itself seen to be turning largely into shales,' especially in its lower part. Beyond this the beds are very imperfectly exposed, except in the deep . vaUey west of Wass, and the position of the Oxford Clay has to be chiefly inferred from the nature of the ground. Between the Coxwold faults these beds are almost entirely obscured by Boulder Clay ; sandy shales are seen in the raUway cutting at the station, v/hich probably belong to this formation, and shaly sandstones are exposed at one or two places between here and Wildon Grange, which must be near the base of the Calcareous Grit ; so that the ''top of the Oxford Clay can be * Memoirs of the Geological Survey. Explanations of Quarfc^r-Shcets 96 N.E., .p. 46, and S5 N.W., p. 45. LOWJER CALCAREOUS GEIT. 47 feirly \yell mapped, l)ut there is no evidence to fix the base of the formation or to trace the outcrop of the Kellaways Eock. Lower Calcareous Grit. — This, which , is the principal rock of the Middle Oolites, forms in this district the great mass of the Hambleton Hills, which rising to the north and west in the great escarpment overlooking the Vale of York,* attains at Black Hambleton a height of 1,300 feet above sea level. It consists principally of cherty sandstones with calcareous bands^ which on the whole are harder and more massive than they have been in the country to the east, so that they are enabled to withstand the action of denudation better, and in a few places as at Peak Scar, Boltby Scar, Whitestone Cliff, and Eoulaton Scar to- form -grand- vertical cliffs. At the former of these- places the following sectiou which shows the siUceous character of the beds was measured : — Section at Peak Scan. Oolitic limestone „ - weathering sandy Hard limestone - - Hard white beds Calcareous beds Hard siliceous bed, dark coloured Siliceous beds, whitish Siliceous calcareous beds, become sandstones further on - - ' - Cherty sandstones Total thickness exposed 97 7 * This northern part of the great central valley of Yorkshire is somiStimeS called the Vale of Mowbray, , ■ 48 CALCAEEOUS GEIT. The basement beds, which are softer and more shaly, are not exposed here. As we trace the Calcareous Grit southwards along the Hambleton escarpment, we find that it becomes split up by calcareous bands and thin limestones ; this is first seen at Boltby, where towards the top of the scar is a thin limestone which appears to be the same as the thick bed to the north at High Paradise and Kepwick, but is certainly not the same as that capping the hill at this spot and dipping eastwards to Cold Kirkby. The following section measured in the scar at Boltby shows this bed, which, however, soon appears to die out and cannot be traced much further to the southward, although there appears to be something of the same sort in the interior valleys : — Section in Boltby Sear. Siliceous beds .... Sandstone, with ciuious markings - Siliceous bed .... Sandstone .... Lime- stone, 16 ft. Siliceous bed 92