Page:The South Staffordshire Coalfield - Joseph Beete Jukes - 1859.djvu/206

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188
SOUTH STAFFORDSHIRE.

and Rugeley. Plants were found in it by Professor Ramsay near Bellbroughton similar to those described by Sir R. I. Murchison and Mr. Strickland in their paper in the 5th vol. of the Geological Transactions.

These Worcestershire marls have a general south-easterly dip, which brings in the Lias east of Hanbury. My colleague. Mr. Howell, partly by himself and partly in conjunction with Professor Ramsay, had mapped the red marls continuously from the Lias of Needwood Forest, by Lichfield. Tamworth, and Birmingham, to Droitwich; and Professor Ramsay informs me that this Lias near Hanbury is precisely similar in mineral character to that of the outliers of Needwood in Staffordshire, consisting of " pale clay below, with interstratified beds of pale bluish argillaceous limestone, covered by brownish white, very thin bedded, micaceous sandstone, containing casts of small bivalve shells." 'The extension of this Lias to the eastward is cut off by an upcast fault running north-west, in which direction the red marls are themselves cut off to the east, and red sandstone brought up against them, probably by the same fault running generally north in a slightly curved line. It is not improbable that this fault runs much farther north, and is in some way connected with the western boundary fault of the coal-field. If so, we have strong presumptive evidence for a fault, running generally north and south with a downthrow to the west for upwards of 40 miles, or from the latitude of Stone to that of Droitwich (see Map, Sheets 72, south-west; 62, north-west and south-west; and 54, north-west).

The New red sandstone between Bromsgrove and the Lickey Hill has a general dip to the south-west and south, and the white sandstone comes in around Bromsgrove, passing under the marls to the southward of it. This white sandstone likewise contains fossil plants at Hill Top near Bromsgrove. It appears to pass laterally as well as downwards, into red sandstone. If we start from the natural boundary of the red marl, south of Bromsgrove, and walk across the country to the pebble beds of the Lickey Hill, a distance of about four miles, we should find that every exposed piece of rock showed a dip to the southward or south-westward, sometimes at an angle even of 10°. Whatever allowance we make, therefore, for undulations of the beds, we must necessarily suppose a very considerable thickness to interpose between the bottom of the red marls and the bottom of the pebble beds. If, however, we pass on to the east side of the Lickey quartz ridge, we shall find the natural boundary of the red marls coming up within a mile of the older rocks, and near Kendal end, within 100 or 200 yards of them. As the beds do not seem to have any greater amount of dip on the east of the quartz ridge than they have on the south-west, we must either suppose the whole of the red sandstone to have thinned out here, and the red marls to overlap nearly the whole of the lower beds, or a very considerable downthrow fault to traverse the east side of the quartz ridge. Moreover, the thick pebble beds lying on the south-west flank of the quartz ridge cannot be traced round its southern extremity, nor seen anywhere to the eastward. It is