摘要:

AbstractThe hornfelsed Skiddaw Slates in the River Caldew, Cumberland, exhibit one of the best displayed sets of folds in the country. Patterns resulting from an analysis of these folds and the structures on the valley sides, indicate that the rocks have suffered several phases of deformation. Evidence is produced to suggest that folding was initiated during the pre‐Bala movements, and re‐folding occurred during the main end‐Silurian orogeny. During the end‐Silurian movements, folding due to collapse under gravity also o

ISSN:0072-1050    

DOI:10.1002/gj.3350070202

出版商:John Wiley&Sons Ltd    

年代:1971

数据来源: WILEY

摘要:

AbstractThe Leintwardine and Whitcliffe Beds of the Ludlow Series outcropping at Tites Point and near Newnham, Gloucestershire, are described and compared with similar beds exposed at May Hill. Data from the Brookend Borehole, 1 ½ miles (2.41 km) south of Tites Point, reveal that southward thickening affects all subdivisions of the Ludlow Series. The occurrence of the Ludlow Bone Bed in the Tites Point outcrop is also recorded

ISSN:0072-1050    

DOI:10.1002/gj.3350070203

出版商:John Wiley&Sons Ltd    

年代:1971

数据来源: WILEY

摘要:

AbstractThe rock types and successions encountered at two localities have been described and interpretated with reference to modern analogues. In the Clifton Down Limestone a cycle of sedimentation is recognised passing from intertidal algalmats, through lagoons, barrier and open shelf deposits and back through the same sequence to intertidal algal mats.

ISSN:0072-1050    

DOI:10.1002/gj.3350070204

出版商:John Wiley&Sons Ltd    

年代:1971

数据来源: WILEY

摘要:

AbstractThe application of sedimentological and other techniques in a detailed small‐scale study of Quaternary meltwater deposits around Pentraeth in Anglesey, North Wales has shown that interpretations based solely on surficial form are incorrect. Previous views held that the sediments were deposited sub‐glacially as eskers by meltwater flowing south‐west from decaying ice in Red Wharf Bay.The present work shows that in general the deposits form a coarsening upwards sequence with distinctive divisions corresponding to the lacustrine, deltaic and fluviatile phases of basin filling. The glacigenic sediments were transported by rivers flowing predominantly south‐eastward and deposited in a shallow lake o

ISSN:0072-1050    

DOI:10.1002/gj.3350070205

出版商:John Wiley&Sons Ltd    

年代:1971

数据来源: WILEY

摘要:

AbstractThe pale‐coloured clays and lignites of presumed Tertiary age from the upper parts of the Mochras borehole (Wood and Woodland 1968) are not the first such materials to be recovered from the existing Welsh landscape. Similar clays and sands, and, occasionally, pebble beds and lignites have been recorded from over twenty localities, preserved beneath Glacial deposits in solution subsidence cavities in the Carboniferous Limestone. The best known such occurrence is the isolated mass at Flimston, Pembrokeshire, which has long been thought to be of Tertiary age (Dixon 1921).The others are scattered along the Carboniferous Limestone outcrop of north Wales between Llandudno in the north‐west and Mold in the south‐east. Their proximity to each other, and records of fossil remains in some of them suggested that it might be possible to effect a regional stratigraphical correlation. Certainly, whatever their age, they form a critical stratigraphical reference in hypotheses concerning the geomorphological evolution of the Welsh landscape.The Flintshire and Denbighshire occurrences are reviewed in the light of information recorded by Maw (1865 and 1867), Strahan (1890) and others, and information forthcoming from recent excavations and augering is presented.It is concluded that, like the pocket deposits of Derbyshire (with which there are numerous analogous relationships) the north Wales pockets are probably solution subsidence outliers of a sheet of fluvio‐lacustrine Tertiary sediments, in part at least 70 m thick, the product of Palaeogene deep weathering, that formerly spread over much of the area of north Wales now occupied by the Alun, Clwyd and Conway cat

ISSN:0072-1050    

DOI:10.1002/gj.3350070206

出版商:John Wiley&Sons Ltd    

年代:1971

数据来源: WILEY

摘要:

AbstractA tight early fold, the Ballybofey anticline, trends south‐eastwards across central Donegal. South‐west of its axial trace the Dalradian strata are inverted so that the rocks high in the Series occur at the lowest structural level, next to, and facing downwards, the supposedly Moinian psammites in the core of the Lough Derg antiform. Rapid facies changes occur in the Dalradian rocks across the Caledonian str

ISSN:0072-1050    

DOI:10.1002/gj.3350070207

出版商:John Wiley&Sons Ltd    

年代:1971

数据来源: WILEY

摘要:

AbstractContinuous seismic profile devices, modified for use in freshwater have been used on Windermere to determine the total thickness of lakebed sediments and the morphology of the underlying bedrock. The survey detected two overdeepened irregularly shaped rock basins. The northerly one approaches 110 feet (34 m) below sea level and contains 70 feet (21 m) of sediment. The corresponding dimensions of the Southern basin are 120 feet (37 m) and 130 feet (40 m) respectively. Glacial scouring is postulated as the origin of the rock basins. Some profiles show two types of sediment; the higher parts of which are known to be Post Glacial.

ISSN:0072-1050    

DOI:10.1002/gj.3350070208

出版商:John Wiley&Sons Ltd    

年代:1971

数据来源: WILEY

摘要:

AbstractThe lithologies and structures of the Dalradian rocks of the Ardsheal Peninsula, Argyllshire are described. The structures associated with the main synformal fold (part of the Appin Syncline) are shown to be F1in age. F2structures cross the Syncline and show progressive development towards the east. The Syncline is correlated and compared with other major F1folds in the region. This interpretation is contrasted with other interpretations of the Syncline as a third‐phase structure which can be correlated with late‐phase folds in the Dalrad

ISSN:0072-1050    

DOI:10.1002/gj.3350070209

出版商:John Wiley&Sons Ltd    

年代:1971

数据来源: WILEY

摘要:

AbstractThis Caledonian pluton exhibits a regular, sub‐vertical banding in which layers of dark, relatively fine grained trondhjemite alternate with layers of light, coarse grained granite. The textures and the presence of cross‐cutting bands of granite indicate that the light bands were derived by potash feldspathization of the trondhjemite. The geometry of the banding indicates that it formed during the “synplutonic” deformation of the pluton, largelyin situ.The bands formed by segregation of alkalies into dilatant zones of movement produced during the deformation of partly consolidate

ISSN:0072-1050    

DOI:10.1002/gj.3350070210

出版商:John Wiley&Sons Ltd    

年代:1971

数据来源: WILEY

摘要:

AbstractThe rocks generally referred to the Kirkby Moor Flags have been mapped in the Kendal area, roughly bounded by Underbarrow, Sedbergh and Kirkby Lonsdale. The succession is divided into four units: the Lower Underbarrow Flags, the Upper Underbarrow Flags, the Kirkby Moor Flags and the Scout Hill Flags. These represent a redefined succession derived from what had been lumped together as ‘Kirkby Moor Flags’. These units correlate with the Upper Leintwardinian, the Whitcliffian and the Downtonian of the Welsh Borderland. Proof that rocks of Downtonian age occur is demonstrated in an unbroken succession of uniform lithology. Ostracodes form an invaluable part of the fauna in both subdivision and correlation of the succession.The fauna of the Kirkby Moor Flags and the Scout Hill Flags can be classified into assemblage groups which possibly represent communities of spec

ISSN:0072-1050    

DOI:10.1002/gj.3350070211

出版商:John Wiley&Sons Ltd    

年代:1971

数据来源: WILEY