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Photos from Kilkenny Bay, North Somerset

These are a few photos from a visit I made in Summer 2006.

The first photo shows mudstones, siltstones and sandstones of the late Devonian Upper Old Red Sandstone believed to have been deposited in wide river flood plains. This section is near the base of the sequence, above are several hundred metres of the ORS (where conformable deposition has occured and there's been no erosion) before the Lower Limestone Shale of the Carboniferous which can be seen further along the coast.

Upper Old Red Sandstone.

The very base of the Upper ORS sequence. The Woodhill Bay Conglomerate rests unconformably on the Lower ORS. To the right can be seen calcrete.

Unconformity at base of the Upper ORS.

Another unconformity: Triassic Dolomitic Conglomerate above the ORS. I'm not sure if this is Lower ORS, or Upper ORS because there is faulting along this section, and the lithology of the two is, in places, similar (at least to an amateur like me!).

Unconformity with Triassic Dolomitic Conglomerate over the ORS.

Cross-stratification in the sandstone of the Upper ORS can be seen above the band of siltstone.

Cross-stratification.

This one's interesting! It looks like some kind of thrust fault, or maybe slumping of sediment at the edge of a channel, but I'll have to go back and have a closer look.

slumping at channel edge or fault?

More cross-stratification. I'm not sure whether this is Upper or Lower ORS. In this context it's caused by sediment in a structure like a bar, or channel edge, migrating as more material is deposited. Where the the cross-stratification terminates is an erosion surface.

Cross-stratification.

A conglomerate within the Upper ORS. I tried aligning the rule in the picture with the bedding, but I think it slipped. More accurately it probably runs diagonally from the bottom left to top right of the rule. Even after correcting for this there looks like some imbrication of the clasts indicating that a significant component of the flow direction would have been from left to right.

Conglomerate within Upper ORS.

2006