Page:The South Staffordshire Coalfield - Joseph Beete Jukes - 1859.djvu/29

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PERMIAN ROCKS.
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entirely of rounded and semi-rounded fragments of mountain limestone and chert, with some pebbles of sandstone that may be millstone grit. It is about 20 feet thick, and is in several places quarried and the limestone pebbles burnt for lime. It occurs again in a field opposite the Gough's Arms, at Great Barr, as also in Baggeridge woods on the west side of the coal-field.

Besides this calcareous conglomerate, many of the sandstones sank through in the pits, or exposed in the quarries and cuttings, are very calcareous, like those before described in the district south of the coal-fields.

The reader must be pleased to bear in mind, that these descriptions of the Permian and New red sandstone rocks are meant to apply solely to the district of the South Staffordshire coal-field and its immediate neighbourhood. The Permian rocks of the neighbourhood are believed to be variable, both in lithological character and in thickness, with perhaps many frequently recurring characteristics, but no uniformity. The thickness of the formation is believed to vary almost indefinitely within the limits of 1,000 or 3,000 feet.


Professor Ramsay, in his paper on the Permian breccias in the Geological Journal,[1] gives a more full and complete account of them than is contained in the above brief observations, and takes a different view as to their origin. He first of all describes those about Enville, where the Permian rocks are largely developed. The breccias there consists of "angular or sub-angular" fragments, "with flattened sides and but slightly rounded edges," embedded in "a deep red hardened marly paste. The pieces collected consist chiefly of fragments of micaceous schist, micaceous sandstone, quartz rock, grey sandstone, chert, purple grit, green sandy slate (one of them polished and scratched), black slate, altered slate, greenstone, felstone, felspathic ash, and reddish eyenite. The last is doubtful. A nodule of ironstone was also observed, and a few quartz pebbles. None of them are larger than 6 or 8 inches in diameter."

He then describes the breccia of the Clent Hills in the following terms:—

"The breccia here consists of pieces of various rock embedded in a hardened red marly paste. Like those near Enville, they are generally angular, or have their edges but slightly rounded. Their sides are often flattened, sometimes polished, and occasionally scratched. They rarely exceed a foot in diameter. On Clent Hill the fragments consist of felstone porphyry, greenstone porphyry, greenstone amygdaloid, ribboned slate, black and green slate, red sandstone, quartz conglomerate, and felspathic ash. In a section near Romsley stones of the same nature were found, including altered sandstone, conglomeritic ash,


  1. On the occurrence of angular, sub-angular, polished, and striated fragments and boulders in the Permian breccia of Shropshire. Worcestershire, &c., and on the probable existence of glaciers and icebergs in the Permian epoch, by Andrew C. Ramsay, F.R.S., F.G.S., Geol. Journal, vol. ii,. p. 185.