Geology of the Trough of Bowland area (SD 65 SW) : part of 1:50,000 Sheets 59 (Lancaster) and 67 (Garstang)

Abstract

This report describes the geology of the 1:10 000 sheet SO 65 SW (Trough of Bowland), part of the 1:50 000 sheets 67 (Garstang) and 59 (Lancaster). The original geological survey was carried out on a scale of 1:10 560 by R. c. Tiddemann, and published as part of the Primary Series Sheets 91NE (1884: New Series Sheet 59) and 91SE (1883: New Series Sheet 67). The present survey was carried out by R. A. Hughes during 1985-86, under the direction of Dr A.J. Wadge, Regional Geologist. The ground to the north of the Miller's House Fault in the extreme northwest of the map was surveyed by Dr A. Brandon in 1984. Most of the area consists of high, open moorland covered by peat bog and heather. Whins Brow [6363 5329] is the highest point at 476m (see Figure 1). The lowest areas are the Brennand and Langden valleys. The Trough of Bowland leads to the major watershed of the Bowland Fells at the Grey Stone of Trough (295m) [6225 5305]. To the north of the watershed is the drainage system of the River Wyre, to the south the River Hodder. Apart from some conifer forestation, farming is entirely pastoral. Sheep graze the poor quality moorland and steep valley sides, while the marginally better pasture of the valley floors supports stock cattle. This is an important water catchment area for the North West Water Authority, supplying the industrial towns of north Lancashire. Structurally the area is dominated by the Sykes and Brennand peri clines which are part of the Ribblesdale Fold Belt. Though these structures have long been referred to as anticlines they are are more accurately described as periclines. Both have an ENE - WSW axial trace, and both have Dinantian rocks exposed in their cores. All the higher ground of the area is made up largely of Namurian sandstones. The "South-western part of the Sykes Anticline" was the subject of a paper by Moseley (1962), in which the succession and structure were described in detail