The Contaminated Gabbro of Easter Saphook near Old Meldrum in Aberdeenshire

1921 ◽  
Vol 58 (4) ◽  
pp. 177-183 ◽  
Author(s):  
H. H. Read
Keyword(s):  
Igneous Rocks ◽  
Geological Survey ◽  
North East ◽  
Rock Types

In North-East Scotland the igneous rocks have been divided into two series, whose times of intrusion were separated by the movements responsible for the foliation and disposition of the crystalline schists of that area.2 With the older series, intruded prior to or during those movements, this paper is not concerned. The younger, or non-foliated, series supplies rock types ranging from peridotite to granite. Gabbro is the chief rock in the large independent basic masses formed by the younger igneous rocks; to the more important of these masses may be given the names of the Huntly, Insch, Boganloch, Haddo, Arnage, Maud, and Belhelvie Masses. For the most part they lie within Sheets 76, 77, 86, and 87 of the 1 inch Geological Survey Map of Scotland.

The Igneous Rocks of the Stanner-Hanter District, Radnorshire

1941 ◽  
Vol 78 (4) ◽  
pp. 241-267 ◽  
Author(s):  
Norman Holgate ◽  
K. A. Knight Hallowes
Keyword(s):  
Alluvial Plain ◽  
Igneous Rocks ◽  
Geological Survey ◽  
North East ◽  
South West

The igneous rocks of the Stanner-Hanter district are included within the Geological Survey I-inch map, sheet 56 S.E., (Old Series), and form three hog-backed hills, Stanner Rocks, Worsell Wood, and Hanter Hill, which are prominent features in the country between New Radnor and Kington, close to the Welsh border. This line of hills trends from south-west to north-east, though the separate ridges are arranged en échelon. Stanner Rocks (I,08I feet), is separated from Worsell Wrood (about 940 feet), by the alluvial plain of the Gilwern Brook, while there is a low col between Worsell Wood and Hanter Hill (I,36I feet).

The Metamorphosed Limestones and Associated Contaminated Igneous Rocks of the Carlingford District, Co. Louth

1932 ◽  
Vol 69 (5) ◽  
pp. 209-233 ◽  
Author(s):  
G. D. Osborne
Keyword(s):  
Igneous Rocks ◽  
The South ◽  
Ordnance Survey ◽  
Igneous Complex ◽  
North East ◽  
The North ◽  
South West ◽  
Carboniferous Limestone ◽  
Contamination Effects

THE Carlingford-Barnave district falls within the boundaries of Sheet 71 of the Ordnance Survey of Ireland, and forms part of a broad promontory lying between Carlingford Lough on the north-east and Dundalk Bay on the south-west. The greater part of this promontory is made up of an igneous complex of Tertiary age which has invaded the Silurian slates and quartzites and the Carboniferous Limestone Series. This complex has not yet been investigated in detail, but for the purposes of the present paper certain references to it are necessary, and these are made below. The prevalence of hybrid-relations and contamination-effects between the basic and acid igneous rocks of the region is a very marked feature, and because of this it has been difficult at times to decide which types have been responsible for the various stages of the metamorphism.

XXV.—Metamorphism in Relation to Structure in the Scottish Highlands

1931 ◽  
Vol 56 (3) ◽  
pp. 621-646 ◽  
Author(s):  
Gertrude Lilian Elles ◽  
Cecil Edgar Tilley
Keyword(s):  
Field Work ◽  
Geological Survey ◽  
Careful Study ◽  
Metamorphic Condition ◽  
Scottish Highlands ◽  
Rock Types ◽  
Long Time ◽  
Metamorphic Zone ◽  
Hand Specimen

The main object of tho present paper is the consideration of the structure of the Central and S.W. Highlands as shown up by the metamorphic condition of the beds. This metamorphic condition has boon studied over the length and breadth of the country, mapped and deduced from very many outcrops in all districts. Sometimes it was possible to superpose the the details respecting the metamorphism upon the 1-inch maps of the Geological Survey, but in many other cases the areas were mapped upon the 6-inch scale. Naturally this work has taken a long time, for it has necessitated the collection of many thousands of specimens, and nearly 3000 rocks have been sliced and examined, since it is not always possible to define the limits of a metamorphic zone with precision by field work alone, and many rock types were encountered that rendered a more careful study advisable than was possible from the mere examination of a hand specimen.

III.—The Gneissose-Granite of the Himalayas

1887 ◽  
Vol 4 (5) ◽  
pp. 212-220
Author(s):  
C. A. McMahon
Keyword(s):  
Igneous Rocks ◽  
Geological Survey ◽  
Short Account ◽  
Near Future

The cause, or causes, which result in the foliation of igneous rocks is a subject which at present occupies the attention of many geologists, and seems likely, in the near future, to lead to some discussion. In view of this, a short account of the foliated granite of the Himalayas may be of interest. It may be as well, however, to preface my remarks by saying that I believe that foliation may be produced in several distinct ways, and the explanation which I offer of the mode in which the foliation of the Himalayan granite has been brought about is only intended to apply to the case of that granite.In the following pages I propose to give a brief summary only of some of the more important results worked out in detail in a series of papers published in the Eecords of the Geological Survey of India; and to add thereto a brief consideration of the question whether the foliation of the gneissose-granite of the Himalayas

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 Dinoflagellate cyst stratigraphy of the Barremian to Albian, Lower Cretaceous, North-East Greenland – a summary

1994 ◽  
Vol 160 ◽  
pp. 68-72
Author(s):  
H Nøhr-Hansen
Keyword(s):  
Lower Cretaceous ◽  
Geological Survey ◽  
Hydrocarbon Potential ◽  
Dinoflagellate Cysts ◽  
East Greenland ◽  
Dinoflagellate Cyst ◽  
North East

As part of studies of the onshore hydrocarbon potential in East Greenland undertaken by the Geological Survey of Greenland (GGU), a project was initiated with the purpose of describing the dinoflagellate cyst stratigraphy of the Lower Cretaceous succession in East Greenland (72°76°N) and correlating the exposed sections throughout the region (Nøhr-Hansen, 1993). Based on the rather sporadic occurrence of macrofossils the Lower Cretaceous sediments of East Greenland was previously dated as Aptian to Albian (Spath, 1946; Maync, 1949; Donovan, 1953, 1955, 1957). Maync (1949) reported the total exposed thickness of the ‘Aptian-Albian series’ to be more than 2000 m, whereas Surlyk (1990) noted that the Lower Cretaceous shale succession reached a cumulative thickness or 1000 m. Furthermore, Donovan (1972) reported that Hauterivian and Barremian sediments were unknown in East Greenland. Dinoflagellate cysts recorded from 40 sections throughout the region have now dated the Lower Cretaceous sequence as Barremian to Albian, and correlation of sections yields a cumulative thickness of approximately 1500m (Nøhr-Hansen, 1993).

scholarly journals Evaluation of the hydrocarbon potential onshore North-East Greenland (72°-75°N)

1991 ◽  
Vol 152 ◽  
pp. 13-16
Author(s):  
L Stemmerik ◽  
F.G Christiansen ◽  
S Piasecki
Keyword(s):  
Geological Survey ◽  
Hydrocarbon Potential ◽  
Petroleum Potential ◽  
East Greenland ◽  
Major Field ◽  
North East ◽  
Geological Information

In 1986 the Geological Survey of Greenland (GGU) initiated a major field and laboratory programme in the onshore areas of North-East Greenland in order to evaluate the petroleum potential and provide basic petroleum geological information for future exploration in the region (Fig. 1).

Porphyry Cu-Au±Mo mineralization hosted by potassic igneous rocks: implications from the giant Peschanka porphyry deposit, Baimka Trend (North East Siberia, Russia)

2021 ◽  
pp. SP513-2020-178
Author(s):  
Andrey F. Chitalin ◽  
Ivan A. Baksheev ◽  
Yurii N. Nikolaev ◽  
Georgy T. Djedjeya ◽  
Yuliya N. Khabibullina ◽  
...  
Keyword(s):  
Tectonic Setting ◽  
Igneous Rocks ◽  
Oxidation States ◽  
Island Arcs ◽  
Porphyry Cu ◽  
North East ◽  
Average Grade ◽  
High K ◽  
High Oxidation ◽  
Other World

AbstractPorphyry Cu-Au±Mo mineralization at Peschanka is hosted by monzodiorite and monzonite intrusions with high-K calc-alkaline to shoshonitic compositions and dated at about 144.1±1.5 Ma, using U/Pb zircon ages. The Cretaceous intrusions are emplaced in a melange of Cretaceous island arcs, a tectonic setting comparable to other world-class porphyry Cu-Au deposits, such as Oyu Tolgoi, Mongolia, and Pebble, Alaska.Abundant primary magnetite contents of the Peschanka intrusions, as well as numerous gypsum and anhydrite veins, reflect the high oxidation states of their parental magmas. This mineralogical interpretation is confirmed by high whole-rock Fe2O3/FeO ratios and high V/Sc ratios of the rocks of up to 1.27 and up to 21.9, respectively. The whole-rock Eu/Eu& ratios of the Peschanka intrusions are ≥1 which is also typical for potassic igneous rocks with high oxidation states. Abundant amphibole and biotite phenocrysts of the intrusions as well as their high whole-rock Sr/Y ratios of up to 225 document significantly high H2O contents of the high-K magmas.Peschanka contains a resource of >9.5 Mt of copper at an average grade of 0.43 wt% and 16.5 Moz of gold at a high average grade of 0.23 g/t and, thus, representing one of the largest undeveloped greenfield copper projects worldwide. The vicinity of Peschanka still offers significant brownfields exploration potential.The hypogene vein-related and disseminated Cu-Au±Mo sulfide mineralization at Peschanka is structurally-controlled by significant NE-trending strike-slips that acted as the conduits for the hydrothermal fluids. The central part of the orebody consists of high-grade N-S trending sheeted quartz-bornite veining with unusually high vein densities. The highest Cu and Au grades are directly correlated with high vein densities.Peschanka is defined by distinct hydrothermal alteration zones including potassic, phyllic, propylitic and argillic assemblages, but a distinct lack of advanced argillic alteration. The mineralization itself is also zoned ranging from a central Mo-Cpy-Bn sulfide assemblage to a peripheral Py-Mt-dominated zone (“pyrite-shell”). Late-stage polymetallic assemblages overprint and surround the main stockwork zone.

scholarly journals IV.—The Glacial Deposits of Northern Pembrokeshire

1906 ◽  
Vol 41 (1) ◽  
pp. 53-87
Author(s):  
T. J. Jehu
Keyword(s):  
Igneous Rocks ◽  
Earth’S Crust ◽  
The West ◽  
Great Abundance ◽  
Glacial Deposits ◽  
North East ◽  
The North ◽  
Earth's Crust

The area embraced in this paper consists of that part of Pembrokeshire which lies to the north and north-east of St Bride's Bay. Bounded on the west by St George's Channel and on the north by Cardigan Bay, it extends to the north-east as far as the mouth of the river Teifi, near Cardigan.That part of the country which lies in the immediate neighbourhood of St David's has, through the laborious researches of the late Dr Hicks and others, become well-known to geologists, and may now be regarded as classic ground. The solid geology of this promontory has given rise to much discussion, and has, perhaps, attracted more attention than that of any other part of the Principality. The reason for this great interest is to be sought in the facts that the rocks of this area are of a very great antiquity, and that the sedimentary series contain the remains of some of the earliest organic forms yet found in the earth's crust, whilst the igneous rocks are also displayed in great abundance and variety, and present us, in the words of Sir Archibald Geikie, with “the oldest well-preserved record of volcanic action in Britain.”

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