The graptolite biostratigraphy of a Llandovery outlier near Llanystumdwy, Gwynedd, North Wales
- 1 May 1981
- journal article
- research article
- Published by Cambridge University Press (CUP) in Geological Magazine
- Vol. 118 (4) , 355-365
- https://doi.org/10.1017/s0016756800032222
Abstract
Summary: Llandovery strata at Llanystumdwy are described. Ninety graptolite species have been identified enabling the establishment of the following zones:acinaces, cyphus, triangulatus, magnus, leptotheca, convolutus, ?sedgwickii, turriculatusandcrispus.The name Llanystumdwy Mudstone Formation is proposed for previously undescribed mudstones cropping out on the River Dwyfor at Llanystumdwy and includes all strata referable to theacinacestoturriculatuszones. Comparison is made between Llanystumdwy and other areas, notably Northern England and Southern ScotlandThis publication has 16 references indexed in Scilit:
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