Stonehead Beck ('Gill Beck')
Also within
Condition (Natural England)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| SD947432 | — | Favourable | 0.58 | 2023-01-19 |
Geology & landscape
Geological Period: Carboniferous
Description
Description A 40 metre sequence of shales with seven marine beds is exposed in the bank of Stonehead Beck, a tributary of 'Gill Beck', by which name the site is internationally known to geologists, clearly demonstrating the boundary between the E2 and Hg goniatite zones. The marked difference ingoniatite and bivalve faunas between the two is well seen here, as is the transition in miospore floras. Gill Beck has been proposed as the boundary stratotype for the base of the Chokerian Stage, a chronostratigraphical unit to be adopted throughout western Europe. Since this horizon may also be used as the dividing line between the upper and lower Carboniferous subsystems equivalent to the Mississippian Pennsylvania boundary in North America and the lower middle Carboniferous boundary in the former U.S.S.R., Gill Beck is a site of considerable international importance. Other Information This site is identified as of international importance in the Geological Conservation Review.