Stratigraphy of the Skiddaw Group between Buttermere and Mungrisdale, Cumberland

Abstract

The Skiddaw Group between Buttermere and Troutbeck is approximately 6,000 feet thick and can be subdivided into four formations which in ascending order are: Hope Beck Slates; Loweswater Flags; Mosser-Kirk Stile Slates; Latterbarrow Sandstone. The coarser elastics exhibit most of the characteristics of sediments deposited by turbidity currents. The source of these deposits is thought to lie to the south. The occurrence of contemporaneous vulcanism in the Loweswater Flags on Watch Hill has been confirmed. Tourmaline and andalusite are recorded for the first time from the metamorphic aureole east of Crummock Water.

The stratigraphy, correlation, provenance and palaeogeography of the Skiddaw Group (Ordovician) in the English Lake District

“…Dixon (1925), Eastwood (1927) and Eastwood et al (1931) later showed that some of Ward's divisions were laterally equivalent, and simplified the succession. Further simplification by Rose (1955) resulted in a two-fold classification and Jackson (1961) added an extra unit below Rose's divisions. Simpson (1967) proposed a different classification comprising eight formations, but gave different names to units now known to be structurally repeated, and took insufficient account of palaeontological evidence.…”

“…This is mainly because of the difficulty in making satisfactory collections of graptolites from the Skiddaw Group, the poor preservation of much of the material, and taxonomic difficulties with many of the earlier Ordovician graptolites. The graptolite zonation used here is based on that of Jackson (1961Jackson ( , 1978, with the addition of two divisions and the redefinition of others (Figs 4,5,12). Approximate correlation with the Australasian graptolitic succession is shown in Fig.…”

“…The suggested presence of contemporaneous lavas in the Watch Hill Formation (Jackson 1961) has now been discounted and the Watch Hill felsite is now recognised as a sill (Hughes & Kokelaar 1993). Molyneux & Rushton (1988) have published detailed biostratigraphical evidence which dates the formation as latest Tremadoc or earliest Arenig (Fig.…”

Stratigraphical Sub-Divisions of the Skiddaw Slates of the Lake District

“…SIR,-In the chapter on the Skiddaw Slates in the recently-published Memoir of the Geological Survey of Great Britain (The Geology of the Country around Cockermouth, Eastwood and others, 1969), a comparison is made in Figure 4 between the sequence in the Skiddaw Slates for the district under description and that in the ground to the south around Keswick and Buttermere, the latter after Rose (1954) and Jackson (1961). Much of the sequence shown for the latter area agrees with that put forward by the writer in a summarized account (The Geology of the Lake District by S. E. Hollingworth and others, 1954) of work which involved detailed mapping on the six-inch scale of the whole of this area (the full results of this work are not yet published).…”

“…The term "Hope Beck Slates" was introduced by Jackson (1961) to denote a distinct formation of slates claimed by him to underlie the Loweswater Flags and to outcrop in an area south-east of Lorton on the northern and western flanks of Dodd and near Scaw Gill. The detailed work by the writer, however, does not confirm the existence of a discrete group of slates in this stratigraphical position.…”