Читать книгу Walking on the Gower. 30 walks exploring the AONB peninsula in South Wales онлайн

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Geology

The continental plate on which Gower has formed was once situated south of the equator and has been drifting northwards over the past 425 million years. As a result, the sedimentary rocks that now comprise Gower were deposited under widely varying climatic conditions, from tropical seas rich in corals to coastal swamps.

The oldest rocks cropping out on Gower are from the end of the Devonian period and they form the cores of the major anticlines. During this period Gower lay in a region where sediment-laden rivers crossed a wide plain between mountains to the north and the sea to the south. The mountains were made of still older rocks whose roots now form much of central and north Wales. The climate at this time was tropical, possibly monsoonal, and the streams carried away coarse sediment from the intense erosion in the hills and deposited it across the braided river channels. In Gower we see pebbly rocks – conglomerates – at the top of the Devonian sequence overlying coarse sandstones, and these form the high ground of Cefn Bryn, Llanmadoc Hill and Rhossili Down.