scholarly journals HEAVY CLASTIC MINERALS AS AN INDICATOR OF GEODYNAMIC SETTINGS OF ACCUMULATION AND PROVENANCE OF CRETACEOUS SEDIMENTS OF THE WEST SAKHALIN TERRANE

2021 ◽  
pp. 68-86
Author(s):  
A.I. Malinovsky ◽  
Keyword(s):  
Large Scale ◽  
Volcanic Rocks ◽  
Source Area ◽  
Heavy Minerals ◽  
Clastic Material ◽  
The West ◽  
Geodynamic Settings ◽  
Eurasian Continent ◽  
Ocean Boundary ◽  
By Products

The article discusses the results of studying heavy clastic minerals from the Cretaceous sandy rocks of the West Sakhalin Terrane, and also presents their paleogeodynamic interpretation. It is shown that in terms of mineralogical and petrographic parameters, the terrane sandstones correspond to typical graywackes and are petrogenic rocks formed mainly by destruction of igneous rocks of the source areas. The sediments were found to contain both sialic, granite-metamorphic association minerals, and femic, formed by products of the destruction of basic and ultrabasic volcanic rocks. The interpretation of the entire set of data on the content, distribution and microchemical composition of heavy minerals was carried out by comparing them with minerals from older rocks and modern sediments accumulated in known geodynamic settings. The results obtained indicate that during the Cretaceous, sedimentation occurred along the continent-ocean boundary in a basin associated with large-scale left-lateral transform movements of the Izanagi Plate relative to the Eurasian continent. The source area that supplied clastic material to that basin combined a sialic landmass composed of granite-metamorphic and sedimentary rocks, a mature deeply dissected ensialic island arc, and fragments of accretion prisms, in the structure of which involved ophiolites.

Mineralogy and origin of the upper Eastend and Whitemud Formations of south-central and southwestern Saskatchewan and southeastern Alberta

1969 ◽  
Vol 6 (2) ◽  
pp. 317-334 ◽  
Author(s):  
P. N. Byers
Keyword(s):  
Chemical Weathering ◽  
Upper Cretaceous ◽  
Volcanic Rocks ◽  
Source Area ◽  
Heavy Minerals ◽  
Major Constituent ◽  
Abrupt Decrease ◽  
South Central ◽  
Mechanical Weathering ◽  
Kaolinitic Clay

The Upper Cretaceous non-marine Whitemud Formation of south-central and southwestern Saskatchewan and southeastern Alberta consists of kaolinitic, metamorphic lithic sands and silts, and kaolinitic clays. The sands and silts are not highly feldspathic as was originally thought. The major constituent is metamorphic lithic grains with minor kaolinitic clay and vermicular kaolin, clear angular quartz, chert, muscovite, and minor volcanic lithic grains and feldspar. The upper part of the Upper Cretaceous Eastend Formation, which conformably underlies the Whitemud Formation, consists of non-marine sands, silts, and clays. Kaolin is very rare. The bulk of the sands are composed of volcanic lithic grains with minor metamorphic lithic grains, clear angular quartz, chert, feldspar, muscovite, and biotite.The contact is characterized by the following changes from the Eastend Formation upward into the Whitemud Formation: an abrupt decrease in volcanic lithic grains and increase in metamorphic lithic grains; the appearance of kaolin and the disappearance of biotite and apatite; a slight increase in clear angular quartz and muscovite and a decrease in feldspar; a general increase in metamorphic heavy minerals; and an increase in the percentage of ilmenite (both as solitary grains and intergrown with magnetite), which is altered to leucoxene.On the basis of mineralogy, the Whitemud Formation is definitely a correlative of the Colgate Member of the Fox Hills Formation in Montana and North Dakota.The upper Eastend and Whitemud Formations were derived from Upper Cretaceous volcanic rocks, Precambrian and Paleozoic metamorphic rocks, and Paleozoic carbonates all situated in Montana. Upper Eastend sediments represent fast mechanical weathering of mountains of freshly extruded volcanic rocks, whereas the Whitemud sediments represent slow chemical weathering and leaching, which predominated once the mountainous volcanic rocks were worn down. This deep chemical weathering altered the volcanic tuffs and flows into kaolinitic clay at the source area; the kaolin of the Whitemud Formation is not derived from the weathering of feldspars at the site of deposition.It is suggested that the Frenchman and Ravenscrag Formations were also derived from Upper Cretaceous and Lower Tertiary volcanic rocks in Montana.

scholarly journals Not simply volcanoes – The Geoheritage of the Cretaceous System in the Land of the Extinct Volcanoes Geopark, West Sudetes (SW Poland)

2021 ◽  
pp. 3-22
Author(s):  
Piotr Migoń ◽  
Edyta Pijet-Migoń
Keyword(s):  
Large Scale ◽  
Volcanic Rocks ◽  
Sedimentary Rocks ◽  
The Other ◽  
The West ◽  
Qualitative And Quantitative ◽  
Deformation Structures ◽  
Volcanic Geoheritage ◽  
West Sudetes ◽  
Sw Poland

Volcanic geoheritage is emphasized as the main asset and distinctive characteristic of the Land of Extinct Volcanoes Geopark in the West Sudetes (SW Poland). However, the geoheritage values of the region are not limited to the legacy of ancient volcanism but include various other elements. This paper explores the contribution of geosites that expose sedimentary rocks of Cretaceous age and landforms developed upon these rocks. Six localities from the Geopark area, included in the comprehensive regional inventory of geosites, are presented. They represent natural and man-made sandstone outcrops and show, among others, lithological variations, small- and large-scale post-sedimentary deformation structures, landforms arising from differential weathering (rock shelters, honeycombs), boulder fields and a sandstone xenolith in volcanic rocks. Next, five localities from outside the Geopark, but still within the Pogórze Kaczawskie region, are described. Qualitative and quantitative evaluation of both groups is attempted, and the results show that, in general, geosites within the Geopark rank higher. However at least two from the other group also have significant geotourist potential. Finally, a brief comparative analysis with other parts of the Sudetes, where Cretaceous sedimentary rocks occur, is offered.

scholarly journals Paleozoic and Early Mesozoic terrigenous deposits of the South-West Primorye: material composition and origin

2020 ◽  
Author(s):  
А.И. МАЛИНОВСКИЙ
Keyword(s):  
Continental Margin ◽  
Active Continental Margin ◽  
Volcanic Rocks ◽  
Sedimentary Rocks ◽  
Source Area ◽  
Material Composition ◽  
Clastic Material ◽  
Power Sources ◽  
Early Mesozoic ◽  
South West

Рассматриваются результаты изучения вещественного состава палеозойских–раннемезозойских терригенных отложений Лаоелин-Гродековского террейна (юго-западное Приморье). Цель исследования – палеогео­динамическая реконструкция обстановок формирования отложений изученных свит, а также определение типов и породных составов их источников питания. Установлено, что отложения свит существенно различаются по вещественному составу, следовательно, они формировались в различных палеогеодинамических обстановках. Отложения кордонкинской свиты накапливались в бассейне, связанном с океанической островной дугой, при этом областью их питания была сама дуга, сложенная основными и средними вулканитами, а также магматическими и осадочными образованиями, входившими в состав ее фундамента. Накопление решетниковской свиты происходило в бассейнах, расположенных на пассивной континентальной окраине. Источниками вещества служили участвовавшие в строении этой окраины кратоны и краевые части рифтов, сложенные гранитоидами, метаморфическими и осадочными породами. Тальминская свита формировалась на активной континентальной окраине в бассейнах рифтогенного происхождения. Источниками кластического материала были краевые части этих рифтов, сложенные кислыми и средними изверженными, а также метаморфическими породами. Полученные результаты позволяют рассматривать Лаоелин-Гродековский террейн как аккреционную призму, сложенную силурийскими, пермскими и триасовыми образованиями, сформировавшимися в различных палеогеодинамических обстановках. Results of material composition study of Paleozoic–Early Mesozoic terrigenous deposits of Laoeling-Grodekovo terrane (South-West Primorye) are collected. The purpose of the study was to reconstruct paleogeodynamic setting of deposits of studied formations, as well as to determine the types and rock compositions of their power sources. It was established that the deposits differ significantly in their material composition and, accordingly, were formed in different paleogeodynamic settings. Deposits of the Kordonka formation accumulated in the basin associated with the oceanic island arc, while the source area was the arc itself, composed of basic and intermediate volcanic rocks, as well as igneous and sedimentary formations that were part of its foundation. The accumulation of the Reshetnikovka formation took place in basin located on the passive continental margin. The sources of the matter were the cratons and marginal parts of rifts participating in the structure of this margin, composed of granitoids, metamorphic, and sedimentary rocks. The accumulation of the Tal’mi formation took place on the active continental margin in the basins of riftogenic origin. The sources of the clastic material were the marginal parts of these rifts, composed of acidic and intermediate igneous Laoeling-Grodekovo terrane as an accreationary prism formed by Silurian, Permian and Triassic deposits, which were formed in various paleogeodynamic settings.

scholarly journals Colonial management as a social field: The Palestinian remaking of Israel’s system of spatial control

2021 ◽  
pp. 001139212110246
Author(s):  
Walid Habbas ◽  
Yael Berda
Keyword(s):  
Large Scale ◽  
Central Component ◽  
Colonial Rule ◽  
Spatial Mobility ◽  
The West ◽  
Social Field ◽  
Spatial Control ◽  
Racial Hierarchy ◽  
Economic Elite ◽  
The Everyday

This article delves into the everyday dynamics of colonial rule to outline a novel way of understanding colonized–colonizer interactions. It conceives colonial management as a social field in which both the colonized and colonizers negotiate and exchange resources, despite their decidedly unequal positions within a racial hierarchy. Drawing their example from the West Bank, the authors argue that a Palestinian economic elite has proactively participated in the co-production of the colonial management of spatial mobility, a central component of Israeli colonial rule. The study employs interviews and document analysis to investigate how the nexus between Palestine’s commercial-logistical needs and Israel’s security complex induced large-scale Palestinian producers to exert agency and reorder commercial mobility. The authors describe and explain the evolution of a ‘Door-to-Door’ logistical arrangement, in which large-scale Palestinian traders participate in extending Israeli’s system of spatial control in exchange for facilitating logistical mobility. This horizontal social encounter that entails pay-offs is conditioned, but not fully determined, by vertical relations of domination and subordination.

Two key switches in regional stress field during multi-stage deformation in the Carboniferous−Triassic southernmost Altaids (Beishan, NW China): Response to orocline-related roll-back processes

2021 ◽  
Author(s):  
Zhonghua Tian ◽  
Wenjiao Xiao ◽  
Brian F. Windley ◽  
Peng Huang ◽  
Ji’en Zhang ◽  
...  
Keyword(s):  
Stress Field ◽  
Large Scale ◽  
Electron Backscatter Diffraction ◽  
Volcanic Rocks ◽  
Structural Deformation ◽  
Regional Stress ◽  
Regional Stress Field ◽  
Multi Stage ◽  
Beishan Orogenic Collage ◽  
Roll Back

The orogenic architecture of the Altaids of Central Asia was created by multiple large-scale slab roll-back and oroclinal bending. However, no regional structural deformation related to roll-back processes has been described. In this paper, we report a structural study of the Beishan orogenic collage in the southernmost Altaids, which is located in the southern wing of the Tuva-Mongol Orocline. Our new field mapping and structural analysis integrated with an electron backscatter diffraction study, paleontology, U-Pb dating, 39Ar-40Ar dating, together with published isotopic ages enables us to construct a detailed deformation-time sequence: During D1 times many thrusts were propagated northwards. In D2 there was ductile sinistral shearing at 336−326 Ma. In D3 times there was top-to-W/WNW ductile thrusting at 303−289 Ma. Two phases of folding were defined as D4 and D5. Three stages of extensional events (E1−E3) separately occurred during D1−D5. Two switches of the regional stress field were identified in the Carboniferous to Early Permian (D1-E1-D2-D3-E2) and Late Permian to Early Triassic (D4-E3-D5). These two switches in the stress field were associated with formation of bimodal volcanic rocks, and an extensional interarc basin with deposition of Permian-Triassic sediments, which can be related to two stages of roll-back of the subduction zone on the Paleo-Asian oceanic margin. We demonstrate for the first time that two key stress field switches were responses to the formation of the Tuva-Mongol Orocline.

NECESSITY, FEASIBILITY, AND CHOICE OF WAY OF INTEGRATING THE GREATER EURASIAN PARTNERSHIP AND THE INITIATIVE CALLED “ONE BELT, ONE PATH”

2021 ◽  
pp. 109-116
Author(s):  
Huirong Zhao ◽  
Keyword(s):  
Russian Federation ◽  
Large Scale ◽  
People’S Republic Of China ◽  
People's Republic Of China ◽  
Republic Of China ◽  
Eurasian Continent ◽  
Large Scale Integration ◽  
The Russian Federation ◽  
Scale Integration ◽  
Political Economic

The article covers the combination of two large-scale integration projects, the Great Eurasian Partnership (Russian Federation) and the initiative called One Belt, One Path (People’s Republic of China). Following the joint statement of the People’s Republic of China and the Russian Federation dated 5 June 2019, which sets out the fundamental provisions of a comprehensive partnership and strategic interaction between the two countries, the author states that the cooperation between Russia and China is conditioned by a number of the political, economic, cultural, and geographical factors; that it can bring tangible benefits not only to Moscow and Beijing, but to almost the entire Eurasian continent, as well as stabilise the global situation. However, in the process of their interaction Russia and China constantly encounter various obstacles, which manifest themselves at the bilateral, regional, and global levels and significantly slow down the implementation of joint projects, which are mutually beneficial. In this work, the author proves that the cumulative intensifying effect on the cooperation between Russia and China can be provided by the strategy of “pairing” integration projects of Russia and China, which the parties have been implementing quite consistently and steadily since 2014.

Chronique d’une écologie décoloniale dans C’est ma terre de Fabrice Bouckat

2020 ◽  
Vol 23 (3) ◽  
pp. 189-205 ◽  
Author(s):  
Françoise Naudillon
Keyword(s):  
West Indies ◽  
Large Scale ◽  
Documentary Film ◽  
Ecological Crisis ◽  
Agent Orange ◽  
Time And Space ◽  
The West ◽  
The One

The documentary film C’est ma terre by Fabrice Bouckat screened during the 2019 edition of Terrafestival is one of the first large-scale films produced locally on the crisis of the chlordecone molecule. This article will examine from a decolonial perspective, how its director, a Martinican with Gabonese origins who lives and works in Guadeloupe, develops a synthetic and universal vision of environmental crises, and thus demonstrates that destruction of ecosystems crosses time and space, cultures and lands, languages and peoples by bringing ecological crisis in the West Indies closer to the one experienced by the Vietnamese victims of Agent Orange.

scholarly journals 14C in the Deep Water of the East Atlantic

Radiocarbon ◽  
1986 ◽  
Vol 28 (2A) ◽  
pp. 391-396 ◽  
Author(s):  
Reiner Schlitzer
Keyword(s):  
Deep Water ◽  
Large Scale ◽  
Bottom Water ◽  
Source Parameters ◽  
Potential Temperature ◽  
Source Terms ◽  
East Atlantic ◽  
The West ◽  
Model Calculations ◽  
Inflowing Water

The renewal of east Atlantic deep water and its large-scale circulation and mixing have been studied in observed distributions of temperature, silicate, ΣCO2, and 14C. 14C variations in northeast Atlantic deep water below 3500m depth are small. Δ14C values range from − 100‰ to −125‰. 14C bottom water concentrations decrease from Δ14C =−117‰ in the Sierra Leone Basin to Δ14C = − 123‰ in the Iberian Basin and are consistent with a mean northward bottom water flow. The characteristic of the water that flows from the west Atlantic through the Romanche Trench into the east Atlantic was determined by inspection of θ/Δ14C and θ/SiO2 diagrams. A mean potential temperature of θ = 1.50 ± .05°C was found for the inflowing water. A multi-box model including circulation, mixing, and chemical source terms in the deep water has been formulated. Linear programing and least-squares techniques have been used to obtain the transport and source parameters of the model from the observed tracer fields. Model calculations reveal an inflow through the Romanche Trench from the west Atlantic, which predominates over any other inflow, of (5 ± 2) Sv (potential temperature 1.50°C), a convective turnover of (150 ± 50) years and a vertical apparent diffusivity of (4 ± 1) cm2/s. Chemical source terms are in the expected ranges.

A Model of Seawater Structure Near the West Coast of Vancouver Island, British Columbia

1963 ◽  
Vol 20 (4) ◽  
pp. 939-967 ◽  
Author(s):  
Robert K. Lane
Keyword(s):  
British Columbia ◽  
West Coast ◽  
Large Scale ◽  
Coastal Region ◽  
Vancouver Island ◽  
Structural Elements ◽  
The West ◽  
Characteristic Structure ◽  
Oceanographic Data ◽  
Vertical Sections

Oceanographic data collected in a line of stations extending seaward of the west coast of Vancouver Island, British Columbia, were reviewed and analyzed. On the basis of these data and the large-scale meteorological processes of wind, insolation, and precipitation, the characteristic structure of temperature and salinity in the coastal region was denned in five temporal stages throughout the year. These stages are presented as vertical sections along the line with characteristic ranges of values to be found in each of the structural elements.

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