Primary Mudstone Unit of Culm Measures | Thickness 3500 to 4000m Named for Holsworthy | |
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Other siltstones, sandstones, conglomerates | ||
The Holsworthy Group is a late Carboniferous lithostratigraphic group (a sequence of rock strata) in north and east Cornwall and Devon in southwest England. The name is derived from the Devon town of Holsworthy. The Group comprises (in ascending order i.e. oldest first) the Crackington, Bideford and Bude formations. In the Launceston area the group is represented by the Bealsmill Formation. It was formerly known as the Upper Culm Group.
References
Holsworthy Group Wikipedia(Text) CC BY-SA