scholarly journals VIII.—The Lower Carboniferous Volcanic Rocks of East Lothian (Garlton Hills)

1895 ◽  
Vol 37 (1) ◽  
pp. 115-126 ◽  
Author(s):  
Frederick H. Hatch

The rich agricultural tract of country that forms the north-western part of East Lothian, undulating uniformly from the foot of the chain of the Lammermuirs towards the Firth of Forth, swells near Haddington into the cluster of the Garlton Hills, and the neighbouring masses of Traprain Law and North Berwick Law.The rocks that build up this elevated ground are lavas and tuffs that were produced during the period of volcanic activity that characterised the deposition of the Lower Carboniferous beds of Scotland. In East Lothian their eruption followed close on the deposition of the sandstones and marls that constitute the base of the calciferous sandstone group.

1874 ◽  
Vol 1 (5) ◽  
pp. 205-210
Author(s):  
Edward Hull

Carboniferous Period.—The Lower Carboniferous rocks, both of the North of England, of Scotland, and of Ireland, afford examples of contemporaneous volcanic action of considerable intensity. The so-called “toad-stones” of Derbyshire, and the great sheets of melaphyre, porphyrite, and ashes of the central valley of Scotland, forming the Kilpatrick, Campsie, and Dairy Hills, appear to have been erupted over the bed of the same sea as that in which were poured out similar materials in County Limerick, forming the well-known Carboniferous volcanic rocks of “the Limerick Basin.” These rocks have been already so fully described by several observers, that I shall confine myself to a very short description, such as is essential to the brief history of volcanic action which I am here endeavouring to draw up.


2020 ◽  
Vol 89 ◽  
pp. 140-153
Author(s):  
Ali Raza

Abstract This paper charts communist print worlds in colonial India during the interwar period. Beginning in the early 1920s, self-declared ‘Communist’ and ‘Bolshevik’ publications began surfacing across India. Through the example of the Kirti Kisan Sabha (Workers and Peasants Party: a communist group in the north-western province of Punjab), and its associated publications, this paper will provide a glimpse into the rich, diverse and imaginative print worlds of Indian communism. From 1926 onwards, Kirti publications became a part of a thriving print culture in which a dizzying variety of revolutionary, socialist and communist publications competed and conversed with the equally prolific and rich print worlds of their political and ideological rivals. Removed on the one hand from the ivory towers of party intellectuals, dense treatises and officious theses, and on the other hand from the framing of sedition, rebellion and fanaticism in the colonial archive, Kirti publications show how the global project of communist internationalism became distinctly provincialized and vernacularized in British India.


1927 ◽  
Vol 55 (2) ◽  
pp. 489-505 ◽  
Author(s):  
Robert Campbell ◽  
James W. Lunn

The shallow synclinal fold termed the Dalmahoy syncline is situated between the north-western flank of the Pentland Hills and the Murieston fault, the most southerly of the five important easterly and north-easterly dislocations which traverse the oil-shale field of West Lothian. The core of the syncline is occupied by rocks belonging to the lower division of the Oil-Shale Group of the Lower Carboniferous. Intervening between these and the Cement-stone Group is a volcanic zone, probably on the same horizon as the Arthur's Seat lavas, consisting mainly of mugearites and basalts which show their greatest development in the Corston Hill district. Along the whole of the southern limb of the syncline is an extensive spread of Upper Old Red Sandstone, but this formation is almost entirely cut out in the northern limb by the Murieston fault, appearing only in the core of a small anticline near Selms.


1914 ◽  
Vol 1 (6) ◽  
pp. 265-271 ◽  
Author(s):  
E. J. Garwood

In my account of the Lower Carboniferous rocks of the North-West of England, published in 1912, I figured an organism, probably the thallus of a calcareous alga, which plays an important part as a rock-builder at the base of the Seminula gregaria sub-zone in Westmorland and Lancashire. More recently, at the meeting of the British Association in Birmingham, I pointed out the need of some distinctive name for this important form, and suggested for it the generic name of ‘Ortonella’, from the village of Orton, near Tebay, in the neighbourhood of which this fossil is specially abundant. Two other structures were mentioned at the same time which occur constantly in microscopic sections of the Lower Carboniferous rocks of the North-West of England and elsewhere. The first of these was alluded to under the general descriptive term ‘festoon structure’, and the other was referred to Gurich's somewhat obscure genus Spongiottroma. In view of the zonal value of these organisms in the North-Western Province and the probability that they will be found to be widely distributed in the Lower Carboniferous rocks elsewhere, I propose here to give a somewhat fuller description of these forms than could be attempted in the limits of a presidential address.


2014 ◽  
Vol 51 (1) ◽  
pp. 56-103 ◽  
Author(s):  
Esther Bordet ◽  
Mitchell G. Mihalynuk ◽  
Craig J.R. Hart ◽  
Jim K. Mortensen ◽  
Richard M. Friedman ◽  
...  

Onset and termination of Eocene felsic volcanism in the Chilcotin Plateau of central British Columbia is constrained between 54.6 and 46.6 Ma by 33 new U–Pb and 40Ar/39Ar isotopic age determinations. Dates were obtained from representative felsic coherent and fragmental volcanic rocks that comprise the Ootsa Lake Group. The resulting chronostratigraphy shows that magma compositions evolved from felsic to intermediate, with no spatial migration of the volcanic activity. Rhyolitic compositions are oldest; and are overlain by dacitic rocks with varied phenocrysts assemblages. In many parts of the Chilcotin Plateau, the Eocene stratigraphy is capped by distinctive vitreous black dacite lavas, which are contemporaneous with andesitic lavas of the Endako Group in the Nechako Plateau to the north. Crystallization ages from Ootsa Lake Group rocks of the Chilcotin Plateau overlap age determinations from correlative rocks of the Nechako Plateau and southern BC. Collectively, this geochronological dataset supports previous suggestions of a voluminous Early Eocene-aged (∼55–46 Ma) period of volcanism in the Intermontane Belt. The abrupt initiation of volcanism, as well as the wide extent, thickness, and compositions that characterize Eocene volcanic rocks may be explained by cessation of subduction and formation of a slab gap beneath British Columbia in the Early Eocene.


1992 ◽  
Vol 154 ◽  
pp. 13-31
Author(s):  
S Piasecki ◽  
L.M Larsen ◽  
A.K Pedersen ◽  
G.K Pedersen

Volcanic rocks, forming hyaloclastites and subaqueous lava flows, were deposited intercalated with clastic sediments in a water-filled basin in West Greenland in the Early Tertiary. Three main stages of basin infilling occurred in the Disko-Nuussuaq area. The distribution of dinoflagellate cysts in the sediments shows that the basin was marine in the first stage and non-marine in the second stage of infilling. In the third stage the basin was displaced towards the south and was marginally marine. The dinoflagellate cysts form a typical mid-Paleocene assemblage which may be correlated with the calcareous nannoplankton (NP) zonation. The stratigraphically lowest investigated localities are coeval with the uppermost part of nannoplankton zone NP4, whereas the overlying localities within the marine basin (first stage) may be correlated with NP5-6. The localities from the non-marine second stage cannot be correlated with the NP zonation because they do not contain dinoflagellate cysts. Localities from the third stage are coeval with NP7-8. Younger volcanics are subaerially deposited. The total known range of the volcanics now falls within the NP3 to NP8 interval, giving a minimum duration for the main plateau-building stage of the volcanism of 4–6 million years. The subaerial basalts have previously been found to be mainly reversely magnetised, with one normally magnetised sequence which can now be stratigraphically correlated with NP4, and thereby identified as anomaly 27. The basalts in East Greenland started erupting during the NP9 zone, so that the volcanic activity in East Greenland largely succeeded that in West Greenland. In relation to the postulated mantle plume in the North Atlantic this means that the volcanic activity started in the peripheral part of the plume and only later switched to the central part.


Author(s):  
L. Kyselevych

The Middle Albian sedimentary complex is deposited on Middle Albian rocks, commonly with no evident unconformity, and includes, along with sedimentary rocks, volcanic activity products. Middlle Albian sediments are distributed almost everywhere within the North Crimean paleodepression. They occur at a depth of 2-5 km and are represented by sedimentary-volcanogenic formations whose generation was caused by intense activity of 6 stratovolcanoes and 3 shield volcanoes. Such formations fail to occur only on a few local sites of the paleodepression and in its northern nearside zone. Sediments are characterized by wide development in their section, along with sedimentary rocks, of pyroclastic and effusive formations whose generation was caused by volcanic activity. The volcanic activity was at its highest during the Middle Albian, which resulted in accumulations of facies-variable volcanogenic-sedimentary strata. Volcanogenic and volcanogeno-clastic Middle Albian sediments occur among marine clay formations as lens-shaped bodies, sheets and flows sometimes stretching over dozens of kilometers, their thickness ranging from a few metres to hundreds. Structural features of volcanogenic-sedimentary strata of different regions depend on their proximity to the centers of volcanic activity and are determined by the nature and characteristics of paleovolcanic eruptions. A closer proximity to paleovolcanoes accounts for an increase in volcanic rocks in the section, with effusive rocks being mostly abundant among them. At a longer distance from the centers of volcanic activity, pyroclastic, volcanogenic-sedimentary and sedimentary deposits become more abundant in the section. Synthesis and analysis of the lithological and petrographic characteristics of Middle Albian sediments, which were based on analyzing deep parametrical and exploration drilling data, made it possible to define 10 main Middle Albian types of lithofacies. These differ in their composition and the share of volcanic activity products found in marine clay sediments. Lithological-facies types of the Middle Albian sediment sections have been defined, as well as the limits of their lateral distribution within the North Crimean paleodepression of the Crimean plains.


1974 ◽  
Vol 110 ◽  
pp. 1-157
Author(s):  
J Muller

The Arsuk ø area is situated along the north-western border of the Early Proterozoic (> 1750 m.y.) mobile belt of South Greenland. Around Arsuk ø reactivated Archaean (> 2500 m.y.) basement is represented by gneiss, amphibolites and migmatites belonging to several lithological series. In the Arsuk basin Early Proterozoic (Ketilidian) supracrustals consist of a group of sedimentary rocks which is overlain by a group of volcanic rocks. The sedimentary Ikerasârssuk Group, with a thickness between 1000 and 1500 m, consists of semi-pelites and pelites with several zones of pyrite-bearing graphite schists and dolomitic limestones. There are also numerous sills of basic rocks which have the same age as the overlying group of volcanic rocks. In some localities the basal member of the group consists of feldspathic quartzites. The volcanic Arsuk Group, the upper part of which is eroded away, has a measured thickness of 4200 m. It consists of pillow lavas, basic massive lavas, volcanic breccias, lapillis and tuffites. There are also some ultrabasic rocks and thin horizons of pyrite-bearing graphite schists with chert. These supracrustal rocks underwent intense deformation at the close of the Early Proterozoic. Three phases can be recognised. The first phase produced N-S to NNE-SSW recumbent folds and the regional schistosity. Refolding during the second phase resulted in folds with E-W to ESE-trending axial planes and a strain slip cleavage. The last phase produced N-S trending structures. The grade of metamorphism during the first phase of deformation corresponds to greenschist facies. In the supracrustals close to the basement recrystallisation in amphibolite facies took place between the first and third phases of folding. This shows the existence of a gradient towards still higher grade metamorphic conditions in the underlying Archaean basement undergoing thorough reconstitution at the end of the Early Proterozoic. As a result of the deformation the stratigraphical unconformity between the Early Proterozoic (Ketilidian) supracrustals and the Archaean basement has been destroyed. During the Gardar period (Middle Proterozoic: > 950 m.y.) and again during the Mesozoic faulting and dyking occurred.


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