Kilmersdon Road Quarry SSSI, Somerset
Disused quarry, exposure site.
Kilmersdon Road Quarry SSSI, Somerset, is important in understanding the early Jurassic geography of this part of western England. The quarry contains fossiliferous limestones and clays of the Lower Lias of the Lower Jurassic Period, which started about 208 million years ago. The marine fossil faunas, particularly the ammonites, indicate that the 6 metres of rock succession exposed represents a period of about 18 million years. In contrast, further north in the Avon Valley, the same time-span is represented by 70 metres of rock. Comparison of the two successions reveals gaps in the succession of fossil faunas at Kilmersdon, where the sea was shallower. Either parts of the Lower Lias were never deposited at Kilmersden or they were eroded away before the succeeding sediments were deposited.
The quarry is long disused and the exposures have been obscured by talus and vegetation, exacerbated by extensive, irresponsible fossil collecting which led to the undermining of faces and fences. The main quarry face has now been restored through the Face Lift Programme and the full succession can once again be seen. A rock store for fossil collecting has been built from the talus in order to draw fossil collecting pressures away from the faces.
Access to the site is currently not available as it is not considered to be in a safe condition.
