Quartz Microfracturing in the North Crop of the South Wales Coalfield

1965 ◽  
Vol 102 (1) ◽  
pp. 59-72 ◽  
Author(s):  
J. C. Roberts
Keyword(s):  
Microscopic Study ◽  
Wide Area ◽  
The South ◽  
Red Sandstone ◽  
The North ◽  
South Wales ◽  
Micro Structures ◽  
Quartz Grains

AbstractA microscopic study of sandstones of Old Red Sandstone and Carboniferous ages along a part of the North Crop of the South Wales Coalfield reveals that the rocks are extensively fractured. The fractures occur in the quartz grains and are often filled with bubble-like inclusions. These planes of inclusion were studied in specimens over a wide area, and are related to the directions of faulting and jointing. The consistency in trend between the macro and micro-structures suggests a homogeneity of the deforming stresses.

scholarly journals X. The fossil flora of the culm measures of North-west Devon, and the palœobotanical evidence with regard to the age of the beds

1905 ◽  
Vol 197 (225-238) ◽  
pp. 291-325 ◽  
Keyword(s):  
Carbonaceous Material ◽  
Physical Structure ◽  
Fossil Flora ◽  
The South ◽  
Lower Carboniferous ◽  
Red Sandstone ◽  
North West ◽  
The North ◽  
South Wales ◽  
Plant Remains

The deposits of Upper Palæozoic age in the south-west of England differ remarkably in their general characters from those developed on the north side of the Bristol Channel. This conclusion applies not only to the Devonian rocks, but also to the succeeding Carboniferous series. In South Wales and Monmouth, the Devonian beds are of the Old Red Sandstone type, whereas, the Devonian succession of North Devon exhibits a marked, though not an entire change, in both petrological characters and palæontological facies; a change which becomes even more marked in the series of limestones, volcanic, and detrital deposits developed in the southern portion of that county. The South Wales coalfield, the largest and most important productive measures in this country, consists of a sequence of coal-bearing strata, resting upon beds of Lower Carboniferous age, for the most part similar in character to those occurring in our other English coalfields. In Devonshire, and in portions of the neighbouring counties of Somerset and Cornwall, a Carboniferous basin of considerable size is developed, occupying more than 1,200 square miles. In many important respects these rocks again differ somewhat markedly from their equivalents in South Wales. They form a succession of deposits of a somewhat abnormal type; being composed of sediments of extremely varied nature and origin, both detrital and organic. They are especially characterised by a general absence of carbonaceous material of any economic importance. These Carboniferous rocks are spoken of as the Culm Measures, a name first applied to them by Sedgwick and Murchison in 1837. These authors in their classic memoir, published in 1840, gave the first accurate description of the physical structure of the beds, and proved conclusively their Carboniferous age. It may be pointed out, however, that De la Beche, in 1834, was the first to indicate the Upper Carboniferous age of that portion of the Culm Measures which forms the subject of this memoir; his conclusion being based on plant remains identified by Professor Lindley. De la Beche also added considerably to our knowledge of the Culm Measures in his ‘Report on the Geology of Cornwall and Devon,’ published in 1839. Since then, John Phillips, Holl, T. M. Hall, and others, and, in more recent times, Messrs. Hinde and Fox, and Mr. Ussher, have all contributed important information on this subject.

A Reinterpretation of the Microlithic Industries of Wales

1963 ◽  
Vol 29 ◽  
pp. 99-132 ◽  
Author(s):  
G. J. Wainwright
Keyword(s):  
Short Distance ◽  
The South ◽  
The West ◽  
The North ◽  
South Wales ◽  
North Wales ◽  
River Valleys

The distribution of Mesolithic sites in Wales is controlled to a great extent by the terrain, for physiographically, Wales is a highland block defined on three sides by the sea and for the greater part of the fourth side by a sharp break of slope. Geologically the Principality is composed almost entirely of Palaeozoic rocks, of which the 600-foot contour encloses more than three quarters of the total area. There are extensive regions above 1,500 feet and 2,000 feet and in the north the peaks of Snowdonia and Cader Idris rise to 3,560 feet and 2,929 feet respectively. Indeed North Wales consists of an inhospitable highland massif, skirted by a lowland plateau and cut deeply by river valleys, providing only limited areas for settlement. The hills and mountains of Snowdonia with their extension at lower altitudes into the Lleyn Peninsula, and the ranges of Moelwyn, Manod Mawr, Arenig Fach and Cader Idris, are discouraging obstacles to penetration, save for a short distance along the river valleys. To the east of these peaks are extensive tracts of upland plateau dissected by rivers, bounded on the west by the vale of the river Conway and cleft by the Vale of Clwyd. To the east of this valley lies the Clwydian Range and further again to the east these uplands descend with milder contours to the Cheshire and Shropshire plains.To the south the district merges into the uplands of Central Wales, which are continuous until they are replaced by the lowland belt of South Wales.

Talitrid amphipods from ocean beaches along the New South Wales coast of Australia (Amphipoda, Talitridae)

Zootaxa ◽  
2012 ◽  
Vol 3575 (1) ◽  
pp. 1 ◽  
Author(s):  
J. K. LOWRY
Keyword(s):  
Western Australia ◽  
New Genus ◽  
New South ◽  
New South Wales ◽  
Original Description ◽  
North Coast ◽  
The South ◽  
Shark Bay ◽  
The North ◽  
South Wales

The sand-hopper Bellorchestia mariae sp. nov. is described from Honeymoon Bay on the north coast of Jervis Bay, NewSouth Wales, Australia. It is the sister species of B. richardsoni Serejo & Lowry, 2008 and appears to have a limited dis-tribution from about Narrawallee in the south to northern Jervis Bay. The distribution of B. richardsoni Serejo & Lowry,2008 is extended from Point Ricardo, Victoria, northwards to Ulladulla on the New South Wales coast. A new synonymyis proposed for the sand-hopper Notorchestia quadrimana (Dana, 1852) which includes N. novaehollandiae (1899) andN. lobata Serejo & Lowry, 2008. It is considered to be a wide-ranging species from Shark Bay in Western Australia aroundthe south coast to at least Maitland Bay in central New South Wales. The beach-hopper Orchestia dispar Dana, 1852 isdescribed from Valla Beach in northern New South Wales and moved to the new genus Vallorchestia. This is the first re-cord of V. dispar since its original description 160 years ago. The beach-hopper Platorchestia smithi sp. nov. is describedfrom Brooms Head, New South Wales, Australia. It is common on ocean beaches from Bendalong in the south to Ballina in northern New South Wales. South of Bendalong beach-hoppers on ocean beaches appear to be absent.

II.—Note on the Lower Culm of North Devon

1904 ◽  
Vol 1 (11) ◽  
pp. 530-532
Author(s):  
Arthur Vaughan
Keyword(s):  
The South ◽  
The North ◽  
South Wales ◽  
Carboniferous Limestone ◽  
Geological Magazine

In the Geological Magazine, August, 1904, pp. 392–403, Dr. Wheelton Hind describes the Lower Culm beds of North Devon and assigns them to the ‘Pendleside’ series.From the original paper dealing with that series I gather that in the North of England the ‘Pendleside’ beds lie above the uppermost zone of the Carboniferous Limestone, and are the equivalents of the Millstone Grit of the South Wales and Mendip areas. Dr. Hind's contention is, then, that the Lower Culm of North Devon was laid down at a time subsequent to the deposition of the whole of the Carboniferous Limestone of the Mendips and South Wales.

The Horizon of the Tillery Vein in Monmouthshire

1956 ◽  
Vol 93 (5) ◽  
pp. 409-417 ◽  
Author(s):  
H. J. Sullivan ◽  
L. R. Moore
Keyword(s):  
The South ◽  
The North ◽  
South Wales

AbstractThe discovery of a hitherto unrecorded non-marine lamellibranch fauna from the Tillery Vein of Monmouthshire indicates that this coal represents a horizon at, or near, the junction of the Phillipsii and Tenuis Zones. The characteristics of the seam in a small portion of the North Crop of the South Wales Coalfield are described in an attempt to account for the limited occurrence of these shells.

scholarly journals XVII. Description of the mineral bason in the counties of Monmouth, Glamorgan, Brecon, Carmarthen, and Pembroke. By Mr. Edward Martin

1806 ◽  
Vol 96 ◽  
pp. 342-347 ◽  
Keyword(s):  
Iron Ore ◽  
The South ◽  
South Side ◽  
The North ◽  
North Side ◽  
South Wales ◽  
East And West ◽  
East End

1. The irregular oval line, delineated on the annexed map (Plate XIV.) shows nearly the inner edge of a limestone bason, in which all the strata of coal and iron ore (commonly called Iron Stone) in South Wales are deposited; the length of this bason is upwards of 100 miles, and the average breadth in the counties of Monmouth, Glamorgan, Carmarthen, and part of Brecon, is from 18 to 20 miles, and in Pembrokeshire only from 3 to 5 miles. 2. On the north side of a line, that may be drawn in an east and west direction, ranging nearly through the middle of this bason, all the strata rise gradually northward; and on the south side of this line they rise southward, till they come to the surface, except at the east end, which is in the vicinity of Pontipool, where they rise eastward.

A Note on an Arthropod from the South Wales Coalfield

1932 ◽  
Vol 69 (6) ◽  
pp. 275-277 ◽  
Author(s):  
Emily Dix ◽  
S. H. Jones
Keyword(s):  
The South ◽  
Light Blue ◽  
Fine Grained ◽  
The North ◽  
South West ◽  
South Wales ◽  
University College ◽  
The University ◽  
Coal Measures

A SMALL Arthropod was discovered by one of us (S. H. J.) in the course of investigations of the Coal Measures of the area around Ammanford, Carmarthenshire, on the north crop of the South Wales Coalfield. It is preserved in a fine grained, light blue shale from the roof of the Little Vein (lower part of the Pulchra Zone of Davies and Trueman), at the Blaina Colliery, Pantyffnon, about one mile south-west of Ammanford. The specimen is in the collection of the University College of Swansea, No. A. 152.

The Carboniferous System in Scotland Characterized by its Brachiopoda

The Geologist ◽  
1860 ◽  
Vol 3 (07) ◽  
pp. 258-265
Author(s):  
Thomas Davidson
Keyword(s):  
The South ◽  
Red Sandstone ◽  
The North ◽  
North Side ◽  
Sea Coast

“This group in Northumberland is seen, westward of Alnwick at Garmitage-bank and Crawley Dean, and on the flanks of the porphyry of the Cheviot in Biddleston Burn, and in the Coquet below Linn Brig; it occupies a considerable area in the south part of Berwickshire, and is largely developed on the Tweed at Carham, Coldstream, Norham, etc.; it is seen underlying the mountain-limestone on the sea-coast from near Lammerton Shiel to Burnmouth; on the north side of Lammermuirs it is intercalated between the Old Red Sandstone, and the mountain-limestone from the Pees mouth to the Cove harbour.” Mr. Tate observes also that the Campsie and Fifeshire beds resemble those of Northumberland.

Sign in / Sign up

Export Citation Format

Share Document