2L62.V U7<5 - D4Z BOUGHT WITH THE INCOME FROM THE SAGE ENDOWMENT FUND THE GIFT OF Henrg W. Sage 1891 gNGiNgRWUBRARX famil 9J.TO JS, Cornell University Library QE 262.L78D42 1870 Geology of the country between Liverpool 3 1924 004 544 205 Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924004544205 Hid GEOLOGICAL SURVEY OF ENGLAND AND WALES. GEOLOGY OF THE COUNTRY BETWEEN LIVERPOOL AND SOUTHPORT, AND EXPLANATION OF GEOLOGICAL MAP, 90 S.E. By Charles E. De Rance, F.G-.S. • Form of the Ground. — The physical configuration of the district comprised in this quarter-sheet divides it into .three areas, at as many different levels. The central and largest portion is a plain varying in elevation from 9 feet above the Ordnance datum-line to the 25 feet contour. It commences at Little Crosby and Sefton, on the south slope of the vaHey of the river Alt, and extends northward beyond the margin of the map. The outer, or seaward portion, is a ridge with a long slope towards the land and a short slope towards the sea, composed of Blown Sand. Upon these slopes, but chiefly on the shorter, are Sand Dunes rising to an elevation of from 50 to 90 feet. The inner, or "landward portion, is an upland plain, the continuation of that described in the " Geology of the country around Wigan." This plain has an average elevation of 60 feet, rising from the low escarp- ment dividing it from the lower plain to Cleve Hill, the highest point within the map, at an angle of rather less than one degree per mile. The base of the low cliff, or escarpment, is generally at the level of the 25 feet contour line, but the real base is below, being concealed by various post-glacial deposits. The entire area comprised in the quarter sheet is a region of formerly obstructed and present artificial drainage, part of the water falling on the lower plain" (which is covered with peat moss), being pumped into the river Alt by a steam pumping engine at Acres Holt, Great Altcar, thence flowing into the estuary of the Mersey, and part being made to flow north to Crossens, north of Southport, where it is pumped into the estuary of the Eibble. Geological Formations. — The following strata are represented on the map : — R - - ./Blown Sand. Kecetst -\ Alluvium. r Keuner - -f Keuper Marls. - j Trias, or New J P " \ Lower Keuper Sandstone. Red Sandstone 1 jj un i er ./Upper Red and Mottled Sandstone. I Pebble Beds. New Red Sandstone. — The. Lower Mottled Sandstone is not represented in this quarter-sheet, but a section occurs at Stand House, Croxteth, in the adjoining sheet, 80 N.W., which has been described in the Survey Memoir on that district. These Stand House Sandstones are cut off on their strike by the " Croxteth Park fault," which com- mences at Roby in 80 N.W., and traverses the sheet now under con- sideration, causing a downthrow to the west until terminated by the Scarisbrick fault on the northern part of the map. 24894. E v Pebble Beds. — This subdivision occupies only a small area in "the district, but two considerable belts of it occur immediately to the south in the Liverpool district. These belts owe their existence, and preservation From denudation, to two large north-westerly faults. One of these traverses the eastern side of Liverpool. " Its line is " marked by the high ridge of Kirkdale and iEv'erton produced by the " harder beds on the upcast side, which consist of reddish-brown "" building stone containing scattered quartz pebbles."* Both of these two great faults lessen in amount northwards, and disappear soon after •entering the pregent quarter-sheet; they have, however, the effect of introducing two small patches of Pebble Beds, the one occurring at Fazakerley, the other at Bootle, the well of the Liverpool Waterworks at the latter place being in this formation. A third patch of this sub- division occurs at Melling, where it is thrown up by the Croxteth Park fault ; it here forms an escarpment in which is a quarry near the ■church. The upper beds are extremely hard, false-bedded, and rather 'coarse, with seams of coloured quartz pebbles which run along the jplanes of current-bedding ; the pebbles vary in length from four inches to the eighth of an inch. The road is cut through the rock and the ihamlet is built upon it, giving the name of " Melling Bocks." The following is the succession of beds at the south end of the quarry : — Bubbly laminated sandstone, 8 feet. Yellow sandstone with red bands, 15 feet. Deep-red sandstone, 3 feet. White freestone, \\ feet. Deep- red sandstone, 5 feet ; this stone is used for building and gate-posts. White freestone, 1 foot, used for tombstones. Deep-red sandstone holding water, which is tapped in a well 60 feet deep at the Inn. This is the lowest bed seen in the quarry ; the beds with pebbles lie above all these, and are only seen at the north end of the quarry. All these beds dip N.N.W. at an angle of from 2° to 3°. Another Section in this patch of Pebble Beds is exposed at Bank Farm Quarry at the edge of the map, where red-coloured, rather coarse sandstones are quarried for building. Upper Mottled Sandstone. — This subdivision occupies rather a larger area than the Pebble Beds, but from its extreme Softness it has been worn into plains and hollows, and afterwards so deeply covered with glacial drift that it is only at two or three points in the whole district that it can be seen at the surface. It has been bored into for wells, at the gaol, and at the workhouse, at Walton Junction ; at the gasworks, Litherland ; at Ellen Grove north of Fazakerley ; and in the wells of the Southport Waterworks Company, at Scarisbrick, and near Ormskirk. The upper beds are of a yellow colour and are often extremely hard. They are seen dipping under the Keuper beds at Cleve Hill, and form a short escarpment at Gbrse Hill, near Ormskirk. The middle beds are soft, of a yellowish colour streaked with red, and are quarried at Bose Hill, near Ormskirk. The lower beds of the Upper Mottled Sandstone are not seen in this district. Lower Keuper Sandstone. — This subdivision occupies a consider- able portion of the map under consideration. The basement bed, as in the Ormskirk country, described by Mr. Hulljf is a hard light-coloured red grit, full of quartz pebbles and cavities, some empty, others filled * Mr. Hull, in "Explanation of Horizontal Section, Sheet 68," page 3. t Geology of the Country around Wigan, and Description of the Geological Survey Map 89, S.W. with marl. These beds occur in the highroad atMaghull; they are- seen resting on the eroded edges of the Upper Mottled Sandstone at Cleve Hill. An interesting section, first observed by Mr. Hull, also occurs at Clent Farm quarry, Maghull. A small northerly fault traverses the quarry with an upthrow to the west, throwing the uppermost red shaly bods of the Keuper Sandstone against the basement bed wil.h quartz pebbles. The former are, however, cut off on their strike by the Croxteth Park fault, which occurs about the eighth of a mile to the. east, bringing up the Upper Mottled Sandstone. The upper beds are rather soft, and are of a yellow or whitish-yellow colour. They are seen at Park Cottage quarry, where the dip is S.E.. at 6° ; at Lydiate quarry, where the dip is N.W: at 6°, in a field at Hatton Hill ; at the quarries in Great Crosby, where the dip is north- westerly ; at Hill Farm quarry, where the beds are horizontal, and much false-bedded; at Altcar quarry, near Hill House, where the dip is N.N.W. at 15°, and the rock is jointed ; at Barton, where a seam of grey marl supports water, which issues as a spring at the corner of Well Lane. Seams of shale also occur in Hill Farm quarry, Little- Crosby, and in. the very fine section of the Lower Keuper Sandstone- exposed In the new railway cutting between Waterloo and Airitree, near the village of Orrell. In this section the upper beds *of the Keuper Sandstone are seen passing conformably up into the basement bed of the Keuper Marls. Occasionally a very hard bed with quartz pebbles occurs near the top of the Keuper Sandstone. It is similar in physical character to that occurring at the base ; and is well seen in the Orrell railway section, and in the quarry at Waterloo View, where the pebbles run along the planes of false-bedding ; and it is also seen at Halsall, in the road and in the brook below the Hall. The pebbles are here very plentiful, and are. of opaque white quartz. Keuper Marls. — The southern boundary of this subdivision is rafcherr uncertain, from the immense thickness of glacial and post-glaciaLbeds- spread over the country. The red marls are seen in the brook, by the footpath from Halsall to Shirdley Hill,. and have also been proved in a. well at Scarisbrick Hall. As the Upper Mottled Sandstones are seen in . the quarry at the south side of Scarisbrick Park,, it is clear that there • is a downthrow fault between the quarry and the welUboring ; this- fault I have called the Scarisbrick &ult. It has a W.S.W. and E.N.E. direction, and terminates the Croxteth Park fault. More to the west the Keuper Sandstones of Halsall and Barton appear to dip naturally under the red and grey marls of Carr Brook., The latter dip to the N.W., but the amount is uncertain. They are also seen in the bottom < of the ponds near Carr Brook below Lower House (Shirdley Hill). At' the bottom of Snig Pot Brook (," Snaje Pod Brookj" of the one-rindi map), a thick bed of ( grey marls occurs between the red beds, and with-, them, are associated thin seams of grey marl, on which pseudomorphous- crystals of salt may be occasionally found. Fibrous gypsum also occurs - in these marls, and sulphate of magnesia is associated with one of the grey seams of marl in the Lower: Keuper Sandstone of the Orrell railway - cutting. A few feet of grey marls cap grey shales which crop to the surface - at Blue Brow, a little knoll covered with Boulder Clay rising from the peat plain between !Southport and Scarisbrick. The upper surfaces of." these shales are coated with grey mica, and they are divided from one* another by thin seams of marl. At the bottom of a well, at the depths of five and a. half yards, the laminations were found to become coarser;. and the shale to assume a flaggy character : at this depth a supply of very hard water was obtained. The surfaces of the shales are covered with ripple marks which run in a N.N.W. direction ; the beds lie in a horizontal position. Faults. — The chief faults have already been incidentally mentioned. The Cleve Hill fault, like that of Croxteth Park, is a downthrow to the west, and like it, is terminated by the Scarisbrick fault. It is seen in several quarries at the top of Cleve Hill, where it throws the basement bed of the Keuper Sandstone against the middle beds of the Upper Mottled Sandstone to the east. The throw of this fault is not less than 600 feet. The Litherland fault is a downthrow to the east, throwing the Lower Keuper against the Upper Bunter Sandstones, the throw being about 500 feet. The small fault in the Orrell railway cutting is also a downthrow to the east, the downthrow being 150 feet. The throw of the fault in the Clent Farm quarry is probably about 380 feet, the downthrow being also to the east. The downthrow of the Scarisbrick fault is to the N.W., the amount being not less than 600 feet. Drift Deposits. With the exception of the crests of two or three slopes, the whole district is deeply covered with drifts of various ages, concealing like a pall the rocks beneath. Only two of these, the recent Alluvium and the Blown Sand, are represented on the map, but the boundaries of all were traced during the survey, and will be published. The following are the subdivisions into which the drifts were found to be capable of separation : — {Blown Sand. Upper " Cyclas " Clay - *1 A „ • „ Upper" Scrobicularia" Clay } Allu ™m. Post-Tertiary [^-^--{K^elas-Clay. f Post-glacial .{Shirdley Hill Sand. Newfr Pliocene -\ *■ Lower Peatl JNEWER MIOCENE -■! g^ (M ; ddle jj^ L " L Lower Boulder Clay. Newer Pmocewe Drifts. Boulder Clay. — In the districts recently surveyed between Chorley and Preston, and Preston and" Blackpool, the Glacial deposits were found to have a distinct triplex arrangement, like that first described by Mr. Hull iii the Manchester and other neighbouring districts, viz., an Upper and a Lower Boulder Clay, divided by a " Middle Sand and Gravel." * In the country between Liverpool and Southport only traces of this Middle Drift occur, and the Lower Boulder Clay is probably alone present. It is generally of a light-red colour, rather soft, with many small pebbles and occasional boulders, beds of mar], and seams of sand. The pebbles and boulders are always erratic, a fragment of Triassic rock being of the greatest rarity. They consist of Silurian, Felspathic, Porphyritic, and Granitic rocks, chiefly from Cumberland. A decom- posed Greenstone, containing Iserine (Titaniate of Iron), often occurs in large masses, especially iii Halsall. The largest boulder in the district * Trans. Man. Lit. Phil. Soc, vol. ii., 3rd series. Geolog. Survey Mem. on the Country around Oldham. occurs in the brickfield near Snape Green, Scarisbrick. The clay is much used for bricks, and occasionally for tiles. The largest brickfields are at Great Crosby and at "Walton junction ; at the last the clay is mixed with an alluvial loam. Many of the pebbles are scratched, but most of them hare been afterwards water-worn. The smaller' boulders are used for paving the roads, something in the ancient Roman fashion. Middle Drift. — Thin beds of sand occur at several places within the district, but it is doubtful whether they are the representatives of the Middle Drift or whether they are merely intercalated beds of sand in . the Lower Boulder Clay. One of these beds occurs in the cemetery at "Walton, across which it runs in a N.E. and S.W. direction, in a belt 80 yards in width, thinning' out at the edges, with a maximum thickness of six feet in the centre. The sand is also seen in the railway cutting between Preston Road and Walton Junction stations, and in the founda- tions of the houses near the station. The sand in' the cemetery is over- laid by 12 feet of Boulder Clay. A thin seam of sand occurs in the Boulder Clay in Mr. Humphrey's brickfield at Great Crosby, and another was cut. through in making the excavation for the reception of the water pipes of the Southport Water Company, between Ormskirk and Scaris- . brick. An undoubted patch of Middle Drift Gravel occurs at an eleva- tion of 125 feet at Rose Hill, near Ormskirk, just off the margin of the map. Lower Peat. — In the account of the form of the ground, at the com- mencement of this paper, the country was described as divisible into an " upper " and a •" lower " plain. These two do not pass insensibly into one another, but are bounded or divided from each other by a low clhTor escarpment. The level of the base of this cliff is apparently about the 25-feet contour, but its true base is concealed by the post-glacial deposits resting on the lower plain. At the base of this cliff of Boulder Clay, and occasionally concealing it, is a bed of sand which forms a range of hillocks or low hills parallel with the cliff. This sand is also found on the upper plain up to an elevation of 175 feet, becoming thinner as greater elevations and greater distances from the sea are reached. It is distributed on the plain most unequally, varying in thickness from 10 feet to two inches in a few yards, occurring on the one slope of a valley and not on the other, on one patch of rising ground and not on the next. In the few small valleys which intersect the upper plain to the east of Ormskirk, the sand rests directly on the bare surface of the Boulder Clay ; but on the plains, both upper and lower, it generally rests upon a bed of peat varying in thickness from one inch to four feet. As the chief bed of peat of the lower plain lies above this sand, I have called it the " Upper Peat," and the bed under consideration the " Lower Peat." Shirdley Hill Sand. — The general distribution and mode of occur- rence of this sand has been described above ; there only remains to give some account of its physical character; The sand, as typically developed at Shirdley Hill, is of a bright-yellow or white colour, the grains being" large and composed of quartz ; it occasionally contains pebbles, generally of white quartz, and more rarely the marine shells Cardium edule and. Turritella communis. Neither shells nor pebbles were observed to occur on the upper plain. The sand is of an ashy-grey colour when overlaid by peat, and of a reddish-brown when by the infiltration of rain-water, or otherwise, the upper three or four feet have become indurated, • The range of low hills, composed of the Shirdley Hill Sand, have much the appearance of a line of old Sand Dunes, formed at the edge of a sea-margin. The lamination in the sand observable at Shirdley and Pye Hills, and the conical hill north-east of Owens Eough, and other small hills in Haskayne* resembles that produced by the wind rather than that caused by tides and currents, but there is no doubt that the sand beneath the peat in the lower plain was thrown down by tidal action. The best sections of the Shirdley Sand on the upper plain occur at Orrell Hill Wood, near Hightown station, at Aintree racecourse, at Aintree station on the Preston line of railway, and at Aintree station on the Blackburn line, where 15, feet of sand are seen resting on Boulder Clay, by the canal in Thornton, where the sand rests upon four feet of peat. The sand of the upper plain hag every appearance of having been blown from the line of old Sand Dunes by westerly winds over the surface of the country. Post-Tektiakt Drifts. Lower " Cyclas " Clay. — The whole of the lower plain, as before de- scribed, is covered with peat, which reaches a thickness in some places of nearly 30 feet. On the western side of the plain the peat rests directly on the Shirdley Hill Sand, but in the central and western por- tion of the plain a bed of laminated grey clay is intercalated. This clay also occurs beneath the peat of Binwose Brook at Seaforth and Waterloo. The peat and clay are seen on the beach at the former place, extending from high- to low-water mark, and apparently occupy- ing the channel of the Mersey, and the roots of large trees may still be seen (April 1868), extending, their ramifications far into the clay beneath. A more extensive submarine forest occurs at Hightown, at the mouth of the Alt. The peat here also rests upon the Lower Cyclas Clay, of which about 8 feet is visible. The base of the clay is nowhere visible within the area of this quarter-sheet, but it has been bored through at Birkdale, a little to the north, and found to be 20 feet thick, resting on Shirdley Hill Sand. The deposit appears to be a lacustrine clay, and contains the shell Cyclas cornea, after which I have 'named it. It is apparently a similar clay to that from which Prof. Edward Forbes has recorded the existence of Cervus megaceros, in the Isle of Man.* Upper Peat. — The peat rests upon the Lower Cyclas Clay in all sub- marine sections, and in all inland sections up to a line from two to three miles inland, running, nearly north and south, along which the clay thins out. Several horizons of forest-surfaces occur in the peat, the largest being that at the base ; the trees chiefly consist of the oak and willow; higher up seams of hazel and spurge with leaves and nuts occur. The average thickness of the peat is 12 feet. In Broad Lane, Great Altcar, a thin seam of freshwater , clay is intercalated in the peat. This is probably the "soft blue silty clay" bored through by Mr. Binney, and described by hjm in his paper on the " Petroleum " found in the Downholland Moss."t The petroleum described by Baron Thenard,| as occurring near Ormskirk was derived from the peat near Downholland Brook to the north of Altcar. The surfaces of all the ditches and watercourses of this tract are covered by a bright- * Memoirs of the Geolog. Survey, vol i., p. 394. t Trans. Man. (Jeol. Society, 1842-43, p. 1 7. % Traite de Chemie, tome 3, p. 445. yellow empyreumatic oil. Mr. Binney states, in his paper, that Mr. Bowman, then of King's College, found 73c united to 69h in a specimen of dark-coloured oil skimmed from the surface of a pool. The oil is sometimes seen floating on the water of the " slacks " in the sand hills, which are then locally called " cary slacks." The appearance is chiefly seen on the western side of the moss, but it also occurs in Flea Moss, near Hightown, and near Hill House in Altcar, on the east side of the moss. The pitchy peat always occurs near the surface, and is probably the result of the decomposition of the peat from above, as suggested by Mr. Binney in 1842. The following is the level, above the Ordnance datum line, of the top of the Lower Cyclas Clay and the base of the Upper Peat at . three localities within the map : — . Crantum Moss, New Cut Lane - - - 1 1 feet. New Moss, New Cut Lane - - 4 „ Headbolt Lane, Ainsdale - - 6 „ The surface of the Lower Cyclas Clay on the beach at the mouth of the Alt is about 6 feet above Ordnance zero. Some of the stumps of oak trees in the submarine forest are nearly two yards in diameter ; this submarine forest and bed of peat is continuously connected with the subterranean forest and the peat mosses inland, passing under the Sand Dunes fringing the coast.* Upper Sckobiculakia and Cyclas Clays. — Besting upon the peat, in the vicinity of the Alt, is a bed of brown clay or alluvium, becoming more sandy at Jhe top, containing Cyclas cornea and other freshwater shells inland and up to three or four miles distance from the sea, when a small variety of Scrobicularia piperata becomes very common, and freshwater forms disappear. Sometimes a bluish clay, similar to the Lower Cyclas Clay, occurs between the peat and the alluvium, and occa- sionally a second seam of peat between the former and the latter, giving the following curious succession : — Marine Clay, Peat, Lacustrine Clay, Peat, Lacustrine Clay. The Upper Lacustrine Clay often thins out, and the two peats coalesce, giving a striking example of how certain coal seams may have been formed, as pointed out by Mr. Binney in 1843. Blown Sand.— The base of the Sand Dunes, both in this district and in the adjoining district of Wirral, was found to consist of a bed of sandy silt, the result of the wind blowing sand into pools in which peat was forming. Often these conditions alternated, the peat and the blowing sand each struggling for mastery. These beds of silt inva- riably contain great numbers of the shell Bithynia tentaculata. I have therefore ventured to name this stratum the Bithynia sand ; it also contains in less abundance other freshwater shells, as the Valvatce, Cyclas cornea, Lymneea, &c. A similar deposit is now being formed in those brooks of the peat district which come under the influence of blowing sand. The tract of Blown Sand is divided in two by the Alt j it varies in width from half-a-mile at Hightown to nearly three miles at Formby. The sand appears to have made very rapid inroads, for in the old maps of Liverpool (Smith's, 1588 ; Speed's, 1610 ; Morden's, 1660) Formby is represented as built on, and surrounded by, a moss ; and in boring through the sand at the present time, a surface of cultivated moss land * The Upper Peat, occupies an area of 26 square miles, -within the quarter-sheet, nearly the whole of which, is below the 25 feet Ordnance contour. with the streets of a town is reached. At the end of the 17th century a sandbank in the sea off Formby connected itself with the coast, from which sand commenced to blow, so that in 1746 the church had to be removed a mile and a half inland. The long axes of all the Sand Dunes run in a W.N.W. and E.S.E. direction, being that of the prevalent wind. The two slopes of a sand hill are unequal, that facing the wind being short, steep, and cliff-like, that on the lee side being a gentle declivity. Water is met with at a depth of 18 inches in the sand-country, the sand being made impermeable to a certain extent by the lime produced by ' the decomposition of sea-shells, by the action of carbonated rain- water. All the shells found in the Sand Dunes belong to species now washed up on the coast, but very few of these are now living in the neighbouring sea, though all are found still living in some portions of the British seas. Many of -the shells appear to have been washed out of a bed of silt, which occurs at low-water mark, between Formby and Birkdale. This silt consists of 75 per cent, clay, 15 sand, and 10 shell-sand or carbonate of lime. LONDON: Printed by Oeoegb E. Eyiuj and William Spottiswoode, Printers to the Queen's most Excellent Majesty. Por Her Majesty's Stationery Office. .. [7793.— 250.— 1/70.]