The borrowdale volcanic series of the dunnerdale fells, lancashire

摘要

AbstractIn the Dunnerdale Fells, south‐west of Coniston, Lancashire, a succession of tuffs, andesites and rhyolites, over 8,000 ft. thick, forming the lower part of the Borrowdale Volcanic Series, has been mapped. These rocks are overlain with marked unconformity by the Coniston Limestone Series, which dips steeply south‐eastwards and oversteps most of the Borrowdale succession in a south‐westerly direction. The Borrowdale Series is affected by two major periods of earth‐movements, the earlier of pre‐Caradoc and the later of Devonian age. The general dip of the Borrowdale Series is eastwards. It shows little folding but is traversed by large tear‐faults with northerly trend. An important belt of faulting closely follows the outcrop of the Coniston Limestone and includes reversed faults. Both sets of faults appear to be of D