PreCambrian rocks are represented by the gneisses of Primrose Hill and schists of Rushton in Shropshire; by the gneisses forming the core of the Malvern Hills, and by the ancient volcanic and other rocks of the Wrekin, Charnwood Forest and Nuneaton.
2
The MT survey confirmed the existence of a Mesozoic sedimentary basin between lava flows and the Precambrian basement.
3
The oil was produced from fractured PreCambrian quartzite on the summits of the buried hills.
4
The oil was produced from fractured Precambrian quartzite on the summits of the buried hills.
5
The Wrekin, the Caradoc and Cardington Hills are isolated outbursts of preCambrian volcanic rocks.
6
Walcott has described a tiny lamellibranch (Modioloides) from the inferior Cambrian, and he reports the gastropod (?) genus Chuaria from the preCambrian.