. Bulletin of the British Museum (Natural History), Geology. 56 W. F. WHITTARD. Fig. 36 Topography of ridges formed by Whittery Volcanic Member, here faulted, with inter- vening hollows excavated in regressive, interbedded shales. View looking south from Rockabank, 600 yd (550 m) south of Wotherton, towards Heightley Barn, 600 yd (550 m) NE of Whittery. that the matrix is not easy to find. There is no evidence, either north or south of the Rockabank outcrop, of volcanic material which approaches this agglomerate in coarseness, though good outcrops of agglomerate showing fragments up to 3-4 in
. Bulletin of the British Museum (Natural History), Geology. 56 W. F. WHITTARD. Fig. 36 Topography of ridges formed by Whittery Volcanic Member, here faulted, with inter- vening hollows excavated in regressive, interbedded shales. View looking south from Rockabank, 600 yd (550 m) south of Wotherton, towards Heightley Barn, 600 yd (550 m) NE of Whittery. that the matrix is not easy to find. There is no evidence, either north or south of the Rockabank outcrop, of volcanic material which approaches this agglomerate in coarseness, though good outcrops of agglomerate showing fragments up to 3-4 in (75-100 mm) occur nearby. The question remains: have we at last a focus for part of the Caradoc vulcanicity in the Shelve Inlier? Mapping fails to show that the rock is in the form of a neck, although the general shape of the outcrop tends to suggest this. On the other hand, the rock appears to be interbedded; but here one should remember that, assuming the neck was originally vertical, the sides of the neck would now be approximately at 45°. The volcanic rocks of the Whittery Volcanic Member in this area form a feature which runs SSW, its position 'stepped' by intermittent dip faults, but occasional indentations run along the strike owing to differential erosion of shale beds in the sequence, and it is clear that not incon- siderable masses of shale occur interbedded in the marine volcanics. On a hillside such as the east side of Marrington Dingle (Fig. 32, p. 48), where the top and bottom of the Volcanic Member can be mapped with reasonable confidence, shale fragments have been brought to the surface by rabbits at several points mid-way up the slope. A shale depression was mapped north of Heightley New Barn, 1650 ft (503 m) NE of Whittery, and may represent a similar condition appearing farther south (Fig. 33, p. 52). The large quarry (Loc. 299) at the southern end of Whittery Wood (Fig. 33) is the original Whittery Quarry and therefore the probable type section for the Volc
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