Gedgrave Hall Pit
Also within
Condition (Natural England)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| TM405485 | — | Unfavourable Declining | 0.65 | 2022-03-30 |
Geology & landscape
Geological Period: Neogene
Description
Description This site consists of two pits of geological importance for the study of the development and stratigraphy of Coralline Crag deposited in the Pliocene age. The two pits show different but complementary features. The larger pit shows over 5 metres of cross stratified crag belonging to the sand wave facies. The original aragonitic fossils are absent due to post depositional solution whilst the calcitic fauna is extremely abraded and poorly preserved. The extent of the abrasion is a reflection of the duration of transport of the carbonate skeletal material. The smaller pit only a few metres away and slightly downslope shows highly fossiliferous Coralline Crag sediments with an abundance of aragonitic molluscs preserved without alteration since deposition. Fragile specimens of Ensis are particularly common. These sediments may prove to represent the unaltered equivalent of those in the larger pit. These pits were almost certainly the localities which prompted Harmer to propose the new stage name 'Gedgravian' to be equivalent to the Coralline Crag in Britain. As the type locality for the Gedgravian, this site is of great stratigraphic importance as well as being a key site in the study of diagenetic post depositional chemical change processes in the Coralline Crag.