. Bulletin of the British Museum (Natural History), Geology. . Fig. 8 View of the Stiperstones, with Tankerville Hollow on left, looking east from Round Hill, 0-7 mile (1 â 1 km) ENE of Shelve hamlet. unless some of the fine-grained micaceous pebbles are highly weathered feldspar in which all traces of twinning are lost. The basal conglomerate, 3 in (7-5 cm) thick, exposed in an excavation by the side of a derelict concrete tank opposite Granham's Moor quarries, is much darker in colour owing to ferruginous and chloritic fragments, and interstitial argillaceous matter. The provenance of the co
. Bulletin of the British Museum (Natural History), Geology. . Fig. 8 View of the Stiperstones, with Tankerville Hollow on left, looking east from Round Hill, 0-7 mile (1 â 1 km) ENE of Shelve hamlet. unless some of the fine-grained micaceous pebbles are highly weathered feldspar in which all traces of twinning are lost. The basal conglomerate, 3 in (7-5 cm) thick, exposed in an excavation by the side of a derelict concrete tank opposite Granham's Moor quarries, is much darker in colour owing to ferruginous and chloritic fragments, and interstitial argillaceous matter. The provenance of the conglomerates, and also of the quartzites, is unknown. If the derivation had been from the east, the direction of the immediate land-region of those times, the content of Uriconian and Longmyndian material would have been much higher than it is; consequently, an along-shore drift of sediment, presumably from the SW, is not unlikely. Also possibly bearing on this problem is the existence at Pontesford, only 1-2 miles (about 2-5 km) away, of repre- sentatives of the Caradoc Series which rest directly upon Pre-Cambrian. There are many geo- logical anomalies here; the unconformity at Pontesford is undeniable yet there is no evidence of such an important hiatus in the corresponding succession of the Shelve Inlier. Important faults occur between the Inlier and the Ordovician outcrop of Pontesford, and two geological regions which were at one time widely separated may have been abruptly collocated by strike-slip faulting in which the movement was essentially horizontal, while downthrow may have brought to about the same present topographical level two deposition surfaces which originally were separated, relative to one another, by a large vertical interval. The entire thickness of the Stiperstones Member is not, however, made up of quartzite and conglomerate. Towards the base are interbedded silvery, greenish-white, soft, soapy shales which have yielded dendroid graptolites and ar
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