Illing's Trenches
Also within
Condition (Natural England)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| SP323942 | — | Favourable | 0.59 | 2013-03-08 |
Geology & landscape
Geological Period: Cambrian
Description
Description This important and classic site was the subject of detailed geological researches in the early20th century and exposes a section through the Abbey Shales of the Cambrian period. Elsewhere these are only sparsely fossiliferous, but here they yield a rich and abundant assemblage of fossils, including over thirty species of agnostid trilobite, numerous other trilobite species, brachiopods, sponge spicules and hyolithids. The fossils which occur allow geologists to make detailed comparisons and correlations between these rocks and the Middle Cambrian Paradoxides paradoxissimus zone of Scandinavia; the fossils found are also similar to those known from equivalent horizons in Newfoundland. The sequence of rocks seen at Illing’s Trenches is the most precisely dated series of rocks known from the middle part of the Middle Cambrian ‘St David’s Series’ anywhere in Britain and is also a key palaeontological site.