scholarly journals III.—On the Metamorphic and Intrusive Rocks of Tyrone

1879 ◽  
Vol 6 (4) ◽  
pp. 154-160
Author(s):  
J. Nolan
Keyword(s):  
Detailed Examination ◽  
Geological Survey ◽  
The North ◽  
Intrusive Rocks ◽  
Metamorphic Series

The rocks I propose to describe in this paper belong to that great metamorphic series which occupies so large a portion of the north of Ireland, extending over most of the counties Tyrone, Londonderry, and Donegal. For the present I shall confine, my observations principally to that portion of them situated about the central parts of Tyrone, from the vicinity of Omagh eastwards and north-eastwards towards Slieve Gallion. This district has “Geological Report on Londonderry and parts of Tyrone and Fermanagh”; but as, during the progress of my work for the Geological Survey, I have had opportunities for a very detailed examination of it, I beg, briefly, to offer some further remarks and conclusions.

scholarly journals VII.—Experimental Researches in Mountain Building

1889 ◽  
Vol 35 (1) ◽  
pp. 337-357 ◽  
Author(s):  
Henry M. Cadell
Keyword(s):  
Detailed Examination ◽  
Geological Survey ◽  
Rock Masses ◽  
Mountain Building ◽  
North West ◽  
The North ◽  
Experimental Researches

Among most of the geologists who had of late years been engaged in investigating the structure of the North-West Highlands, and especially among those who did not concur in Murchison's explanation of the phenomena exhibited there, it was a growing belief that great overthrusts had been largely instrumental in producing the remarkable stratigraphical relations of the rock masses of that region. After a most careful detailed examination of the ground by the Geological Survey, the existence and importance of such thrusts was not only placed beyond a doubt, but a variety of additional remarkable structures were discovered, which open up new fields of investigation to the physical geologist.

scholarly journals The stratigraphy of the marine Quaternary deposits in West Greenland

1950 ◽  
Vol 2 ◽  
pp. 1-142
Author(s):  
D Laursen
Keyword(s):  
Present Report ◽  
Detailed Examination ◽  
Geological Survey ◽  
The South ◽  
Quaternary Deposits ◽  
West Greenland ◽  
Marine Deposits ◽  
The North ◽  
Field Investigations

The present report deals with the Quaternary marine deposits in West Greenland. The area in question extends from Kugssineq, Svartenhuk peninsula, in the north to the settlement of Sukkertoppen in the south. The field investigations for the paper have been made partly in 1939, partly in 1946, last-mentioned year under the auspices of Grønlands Geologiske Undersøgelse (abb. G.G.U., i. e. Geological Survey of Greenland). All localities visited are described with added lists of the collected shells. On the basis of the investigations made it will be demonstrated that the stratigraphy of the layers at Orpigsôq drawn up by Jensen and Harder in 1910 (30) is applicable to all the area investigated. Furthermore a detailed examination is made of the petrographic structure, the content af shells, and the levels of the various horizons, a discussion of a few errors, and ultimately an attempt at a correllation of the Quaternary marine layers of Greenland with the corresponding postglacial layers of Iceland, Norway, and Denmark.

scholarly journals III.—Fossiliferous Oldhaven Beds at Ipswich

1903 ◽  
Vol 10 (10) ◽  
pp. 453-456 ◽  
Author(s):  
Henry Bassett
Keyword(s):  
Great Part ◽  
Geological Survey ◽  
Pebble Bed ◽  
Railway Line ◽  
The North ◽  
North Side ◽  
London Clay

In the “Geology of the Country around Ipswich, Hadleigh, and Felixstowe” Mr. Whitaker drew attention to the probable existence of Oldhaven Beds at Ipswich. On p. 11 he gives particulars of a section in Stoke brickyard. Below the London clay at this spot occurred fine buff sand separated from the Clay by a thin pebble-bed containing fragments of shells. The buff sand was doubtfully referred to the Oldhaven Beds, while it was thought that the pebble-bed should also be included with these rather than regarded as a basement-bed of the London Clay. Below this doubtful Oldhaven sand occurred sands and mottled clays of the Reading Series. It was shown in the memoir that this pebble-bed occurred over a great part of this district with an outcrop along the valleys of the Gipping and the Brett. As a rule it rests on sands referred to the Reading Series, and is classed by Mr. Whitaker sometimes as basement-bed of the London Clay and occasionally as Oldhaven Beds.Recently in Ipswich I came across a very clear section of these beds in one of the brickfields, and as they here show a rather unusual facies it seems worth while to draw attention to the section, especially as the beds contain many fossils at one spot. The section occurs on the north side of Messrs. Bolton & Laughlin's brickfield between the Norwich and Henley Roads. The brickfield is situated almost due north of Brook's Hall, and about 100 yards south of the railway line, but apparently at the time of the Geological Survey there was no brickfield at this spot; the pebble-bed, however, was shown in another pit (which still exists) a little further westward, and was included in the basementbed of the London Clay by Mr. Whitaker.

Stages of Late Palaeozoic deformation and intrusive activity in the western part of the North Patagonian Massif (southern Argentina) and their geotectonic implications

2008 ◽  
Vol 146 (1) ◽  
pp. 48-71 ◽  
Author(s):  
W. VON GOSEN
Keyword(s):  
Regional Metamorphism ◽  
The North ◽  
Magmatic Rocks ◽  
Late Palaeozoic ◽  
Intrusive Rocks ◽  
Gondwana Margin ◽  
Intrusive Activity ◽  
Magmatic History ◽  
Crust Deformation ◽  
Deformational Event

AbstractAnalyses of structures in the western part of the North Patagonian Massif (southern Argentina) suggest a polyphase evolution, accompanied by continuous intrusive activity. The first two deformations (D1, D2) and metamorphism affected the upper Palaeozoic, partly possibly older Cushamen Formation clastic succession and different intrusive rocks. A second group of intrusions, emplaced after the second deformational episode (D2), in many places contain angular xenoliths of the foliated country rocks, indicating high intrusive levels with brittle fracturing of the crust. Deformation of these magmatic rocks presumably began during (the final stage of) cooling and continued under solid-state conditions. It probably coincided with the third deformational event (D3) in the country rocks. Based on published U–Pb zircon ages of deformed granitoids, the D2-deformation and younger event along with the regional metamorphism are likely to be Permian in age. An onset of the deformational and magmatic history during Carboniferous times, however, cannot be excluded. The estimated ~W–E to NE–SW compression during the D2-deformation, also affecting the first group of intrusive rocks, can be related to subduction beneath the western Patagonia margin or an advanced stage of collisional tectonics within extra-Andean Patagonia. The younger ~N–S to NE–SW compression might have been an effect of oblique subduction in the west and/or continuing collision-related deformation. As a cause for its deviating orientation, younger block rotations during strike-slip faulting cannot be excluded. The previous D2-event presumably also had an effect on compression at the northern Patagonia margin that was interpreted as result of Patagonia's late Palaeozoic collision with the southwestern Gondwana margin. With the recently proposed Carboniferous subduction and collision south of the North Patagonian Massif, the entire scenario might suggest that Patagonia consists of two different pieces that were amalgamated with southwestern Gondwana during Late Palaeozoic times.

scholarly journals X.—On the Greenstone and Associated Rocks of the Manacle Point, Lizard

1889 ◽  
Vol 6 (9) ◽  
pp. 425-427
Author(s):  
Alexander Somervail
Keyword(s):  
Good Reason ◽  
Geological Survey ◽  
The South ◽  
Main Mass ◽  
Considerable Distance ◽  
The North ◽  
North Side ◽  
South Wall

On De La Beche's Geological Survey Map of Cornwall are three colours representing the associated rocks at, and on each side of the Manacle Point. The Point itself and for a considerable distance south of it is represented as a greenstone. Partially encased in the greenstone and to the south of it is gabbro, which forms the main mass of this rock in the Lizard district. On the north side of the greenstone which forms the extreme south wall of Porthonstock Cove is hornblende-schist, which with some serpentine and other rocks terminates against the killas, or slates near Porthalla.Several observers with seeming good reason have drawn attention to the fact that the greenstone as represented on the map is made to cover much too large an area to the south, and that any one walking from this direction, or the reverse, finds gabbro where the former rock was expected to occur.

Attitudes to reform: political parties in Ulster and the Irish land bill of 1881

1985 ◽  
Vol 24 (95) ◽  
pp. 327-340
Author(s):  
Francis Thompson
Keyword(s):  
Political Parties ◽  
Detailed Examination ◽  
The Other ◽  
The South ◽  
The North ◽  
Other Hand ◽  
Previous Decade ◽  
History Of

The Irish land act of 1881, it is generally agreed, was a victory for the Land League and Parnell, and nationalist policy with regard to the act and the attitude of southern tenants towards it have been many times subjected to detailed examination by historians of this period. In these analyses of the events of 1880–81, however, little reference is normally made to the part played by the different parties and interests in the north of the country. It is often assumed, for example, that the Ulster tenants held aloof from the campaign for reform, lending no more than occasional vocal support to the agitational efforts of tenants in the south and west. Indeed, they were later excoriated by William O'Brien, Michael Davitt and others not only for giving no support to the land movement but also for sabotaging Parnell's policy of testing the 1881 act by precipitately rushing into the land courts to take advantage of the new legislation: ‘that hard-fisted body of men, having done nothing themselves to win the act, thought of nothing but turning it to their own immediate use, and repudiating any solidarity with the southern and western rebels to whom they really owed it’. If, however, northern tenants were harshly judged by nationalist politicians in the years after 1881, the part played by the northern political parties in the history of the land bill has been either ignored or misunderstood by historians since that time. The Ulster liberals, for example, are rarely mentioned, the implication being that they made no contribution to the act even though it implemented almost exactly the programme on which they had been campaigning for much of the previous decade. The northern conservatives, on the other hand, are commonly seen as leading opponents of the bill, more intransigent than their party colleagues in the south, ‘quick to denounce any weakening of the opposition’ to reform, and ‘determined to keep the tory party up to the mark in defending the landlord interest’

II.—Notes on the Pleistocene of the North-West Territories of Canada, North-West and West of Hudson Bay

1894 ◽  
Vol 1 (9) ◽  
pp. 394-399 ◽  
Author(s):  
J. Burr Tyrrell
Keyword(s):  
Geological Survey ◽  
Hudson Bay ◽  
North West ◽  
The Past ◽  
North Shore ◽  
The North ◽  
South West ◽  
North West Territories

In the extreme northernmost part of Canada, lying between North Latitudes 56° and 68° and West Longitudes 88° and 112°, is an area of about 400,000 square miles, which had up to the past two years remained geologically unexplored.In 1892 the Director of the Geological Survey of Canada sent the writer to explore the country north of Churchill River, and south-west of Lake Athabasca;in1893 the exploration was continued northward, along the north shore of Athabasca Lake

scholarly journals Investigations of detrital zircon, rutile and titanite from present-day Labrador drainage basins: fingerprinting the Grenvillean front

1969 ◽  
pp. 77-80
Author(s):  
Tonny B. Thomsen ◽  
Christian Knudsen ◽  
Alana M. Hinchey
Keyword(s):  
Newfoundland And Labrador ◽  
Sedimentary Basins ◽  
Geological Survey ◽  
Drainage Basins ◽  
Grenville Province ◽  
Collaborative Project ◽  
North West ◽  
North East ◽  
The North ◽  
Three Samples

A multidisciplinary provenance study was conducted on stream sediment samples from major rivers in the eastern part of Labrador, Canada (Fig. 1). Th e purpose was to fi ngerprint the sources that deliver material to the stream sediments and to the reservoir sand units deposited off shore in the sedimentary basins in the Labrador Sea. We used a multimineral U-Pb geochronological approach employing rutile and titanite in addition to zircon to obtain unbiased age data. Th e purpose of this was to characterise the diff erent igneous and metamorphic episodes that occurred in Labrador, which is an area with highly variable geology characterised by the Palaeoproterozoic south-eastern Churchill province in the north-west, the Archaean Nain plutonic suite in the north-east, the Palaeoproterozoic Makkovik province in the east and the Mesoproterozoic Grenville Province to the south. Th e fi eld work was carried out in 2012 and 2013 and the study is a collaborative project between the Geological Survey of Denmark and Greenland and the Geological Survey of Newfoundland and Labrador. In this paper we focus on three samples from the southern part of the study area where two parts of the Grenville orogeny are found (Fig. 1).

scholarly journals Field work in the north of the Ivisârtoq region, inner Godthåbsfjord, southern West Greenland

1983 ◽  
Vol 115 ◽  
pp. 49-56
Author(s):  
B Chadwick ◽  
M.A Crewe ◽  
J.F.W Park
Keyword(s):  
Field Work ◽  
Geological Survey ◽  
West Greenland ◽  
North West ◽  
The North ◽  
Field Investigations ◽  
New Findings ◽  
Host Rocks

The programme of field investigations in the north of the Ivisartoq region begun in 1981 by Chadwick & Crewe (1982) was continued in 1982. Julia Park began mapping the Taserssuaq granodiorite, its host rocks and the Ataneq fault in the north-west. Dur team was joined by D. Bellur, Geological Survey of India, nominally as an assistant. In this report we present only summary notes of new findings relevant to the interpretation of the geometry and chronology of this segment of the Archaean crust in southern West Greenland. We use the established terminology for the Archaean rocks of the Godthåbsfjord region.

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