Topics/Geology from rail journeys: the Settle-Carlisle Railway

摘要

'The strata passed through on the whole line were Shale, Clay, Washing and Boulders, Red Sandstone, Sand and Mar'. Wildman's Almanac (Settle) 1873. One of the more attractive ways of surveying geology of an area is from the vantage of a railway carriage. True, you can not derive the satisfaction of a detailed analysis of the petrology or structures. but the journey does allow an appreciation of the spatial aspects and scale of geological processes. The geology along the route of the Settle-Carlisle line mainly consists of Carboniferous and Permo-Triassic rocks resting unconformably upon a basement of Lower Palaeozoic rocks (Fig. 1). Throughout this article modern stratigraphical terminology is used, although the more traditional names are given in parentheses. The highlights of the geology include karst topography associated with the Dinantian limestones. Silesian (Namurian) cyclothems on the 'three peaks' and rugged sandstone ('grit') scarps are found along the western edge of the Askrigg Block. Dune and evaporitic Permo-Triassic deposits and the Lower Palaeozoic rocks of the tectonically complex Cross Fell inlier, which is scenically emphasized by conical hills termed 'pikes', are the main constructs of the Vale of Eden half graben. Impressive distant views of the Lake District Fells may be had north of Appleby. A classic Quaternary drumlin field that exhibits a complex history of ice movement covers the valleys of the entire area.