The Silurian strata of the Howgill Fells

Rickards, Barrie

Abstract

[From the Introduction:]

The Howgill Fells form a most distinct topographical feature extending from N.W.Yorkshire into Westmorland. In plan they occupy a broadly triangular area with the town of Sedbergh at the southern apex. Tebay forms the north western limit of the fells and Ravenstonedale village the north east. The broad, flat Ravenstonedale valley between the village of the same name and Tebay in the west, bounds the northern edge of the hills whilst the deep valley of the R.Lune between Tebay and Sedbergh effectively demarcates the western margin. The Cautley valley in the east, which forms the pass through to Ravenstonedale from Sedbergh, is at a somewhat higher level than the Lune valley and has a watershed east of Barter Fell. The fells themselves stand out in marked contrast to the Carboniferous country to the east and north, and consist of deeply dissected rounded hills rising to well over 1500 in most cases, whilst Great Dummacks and The Calf.exceed 2000'.

The writer has mapped in detail an area in the eastern half of the fells some 6 miles long by 3-4 miles. wide and has carried out reconnaisance mapping in the rest of the fells. In the north the detailed map extends from the Cautley valley as far west as Bowderdale, and in the south almost as far west as the River Lune. The area is covered by the following Ordnance Survey 6" sheets:- SD69 NW,NE,SW,SE; SD79 NW,SW; NY60 NE,NW,SW,SE and NY70 SW. Text fig.1a illustrates the geographical and geological setting of the area. The Silurian rocks of the northern part of the Howgill Fells are overlain unconformably by Carboniferous conglomerates; limestones and shales, the actual unconformity being well exposed in several stream sections. To the east the Silurian and Ordovician are faulted against Carboniferous rocks along the line of the Dent Fault, whilst to the south the unconformable red conglomerate at the base of the Carboniferous forms a natural geological boundary. The Ordovician rocks are exposed in a series of complicated inliers in the Cautley valley and these are succeeded to the north and west by successively higher Silurian divisions until the Bannisdale Slates are seen in the region of the R.Lune, N.W. of Sedbergh and in the gentle slopes into Ravenstonedale. To the south of Sedbergh are the Barbon and Middleton Fells, again consisting predominantly of Silurian strata, and to the west the main Lake District outcrop of the Silurian.

Citation

Rickards, B. The Silurian strata of the Howgill Fells. (Thesis). University of Hull. https://hull-repository.worktribe.com/output/4221613

• Thesis Type: Thesis
• Deposit Date: May 30, 2019
• Publicly Available Date: Feb 23, 2023
• Keywords: Geology
• Public URL: https://hull-repository.worktribe.com/output/4221613
• Additional Information: Department of Geology, The University of Hull
• Award Date: Aug 1, 1963