Abstract
LONDON. Geological Society, Nov. 16.—W. D. Lang, L. R. Spath, L.R. Cox, and Helen Marguerite Muir-Wood: The bennite-marl of Charmouth, a series in the Lias of the Dorset coast. Pale marl, lying in the Liasbove beds with Echiocera and below those with Androgynoceras, extend along the Dorset coast foF about four miles. Forming the third, and highest, Lias precipice on Black Ven, they are soon truncated by the eastern. slope of that cliff, but reappear eastwards to form the second precipice at the western end of Stonebarrow Cliff. They descend to the beach at Westhay Cliff, and form a gentle syncline, so that the lowest beds are carried beneath the tide opposite Westhay Water. They rise for a short distance on Ridge Cliff, but soon are thrown down and out of sight by the Ridge Fault. Thereafter only the highest beds of the belemnite-marls are seen. The marls contain few beds in which ammonites are well preserved. Ammonite-remains, however, are to be found throughout, and although the preservation is often poor, a sequence has been established. Except at a few horizons, belemnites are not common below the belemnite-maris; but they abound in the mans, and, if the outstanding forms are carefully collected, they show, like the ammonites, limited ranges and a crowded sequence. The gastropod molluscs are few in number of species and not suitable for showing zonal distribution. The same may be said of the lamellibranchs. The ammonites are only of local value in establshing a sequence.
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Societies and Academies. Nature 120, 860–862 (1927). https://doi.org/10.1038/120860a0
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DOI: https://doi.org/10.1038/120860a0