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Photos from the Somerset coast (Lilstock to Quantoxhead)

These are photos from several visits I made to this area in 2006. The Somerset coast between Lilstock and Quantoxhead is world famous for its outcrops of Hettangian and basal Sinemurian Stage Lower Lias and is designated an SSSI. Also exposed are the Mercia Mudstone Group and Penarth Group of the Triassic, whilst the wide foreshore exposures of Lias also give an interesting 3D picture of geological structures such as faults and folds. Various fossils can be found, including a wide range of ammonite species both in fallen blocks from the cliff, and insitu in the shale exposed on the shore. However, the insitu specimens are protected by the SSSI and are invaluable to those undertaking research in the field of Lower Jurassic stratigraphy. There's nothing to stop you photographing them, though, and I've been doing so myself in an attempt to work my way around the arcane subject of ammonite zones and subzones.

The first photo shows the alternating bands of limestone and shale typical of the Blue Lias Formation. This was taken to the west of Kilve.

The Blue Lias formation

This is a view from the cliff looking down onto the foreshore in the same area. You can see how the sea has partly eroded some of the limestone beds, and see the direction they dip. In some areas of the coast you can see clearly how the beds have been folded, and make out the line of plunging anticlines and synclines. The area is heavily faulted, too, and these can be readily traced from the cliff across the foreshore.

The Blue Lias formation

This is a major fault to the west of Quantoxhead. The Twyning Mudstone Formation can be seen to the right of the picture and the Blue Lias Formation to the left. There's also a block of Lilstock/Westbury Formation in there between them.

A major fault

This was taken to the east of Lilstock where water has eroded a bed of limestone into some quite photogenic shapes.

Erosion of limestone

2006