摘要:

AbstractColonsay is a small island in the Inner Hebrides, about 100 km. south of Skye. The main part of the succession, which is about 2 km. thick, consists of phyllites, fine dark sandstones and flags, occasionally graded, with major intercalations of coarse current‐bedded arkose and, near the top, dolomitic limestone horizons. This series rests with a sharp contact (probably a slight unconformity) on a sequence of graded greywackes and mudstones, not less than 2 km. thick, most of which outcrops to the south in Oronsay, and in Islay, where it rests unconformably on the Lewisian basement. The greywackes and arkoses indicate that currents moved mainly northeastwards.A comparison of the Torridonian rocks to the north with those in Colonsay suggests the equivalence of the beds above the greywackes with at least part of the Diabaig in Skye. Three major fades are distinguished in the Torridonian; the greywacke, Diabaig and arkose fades, and it is tentatively suggested that they mark stages in the infilling of a major sedimentary basin or trough of which the present Torridonian outcrop forms only the western margi

ISSN:0072-1050    

DOI:10.1002/gj.3350030111

出版商:John Wiley&Sons Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractA detailed geological map of this northeastern part of the Lleyn peninsula is provided for the first time. The area consists largely of a suite of Caledonian intrusions, in which many distinctive rock‐types can be recognised, but the majority are of granodioritic affinities. These rocks are described in detail and eighteen chemical analyses of them are given. The relations of intrusions to the structural features of the area are discussed and the probable geological history describe

ISSN:0072-1050    

DOI:10.1002/gj.3350030112

出版商:John Wiley&Sons Ltd    

年代:1962

数据来源: WILEY

摘要:

AbstractBlack graptolitic shales of approximatelyD. clinganiage were seen resting on flaggy beds with an Upper Longvillian fauna, which are taken to belong to the Upper Ash Group of Elles. This section conflicts with the details published concerning the nearby Conway railway cutting and an attempt is made to correlate the two sections. The work shows that volcanism at Conway ended within the same stage of the Caradoc as in Snowdonia, not earlier as formerly supposed.

ISSN:0072-1050    

DOI:10.1002/gj.3350030113

出版商:John Wiley&Sons Ltd    

年代:1962

数据来源: WILEY

ISSN:0072-1050    

DOI:10.1002/gj.3350030116

出版商:John Wiley&Sons Ltd    

年代:1962

数据来源: WILEY