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Kuznetsk Basin (3)
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sulfides
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Primary terms
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absolute age (3)
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Africa
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East Africa
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Ethiopia (2)
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Southern Africa
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Karoo Basin (1)
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South Africa (1)
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Antarctica
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Transantarctic Mountains
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Beardmore Glacier (1)
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Coalsack Bluff (1)
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Arctic region
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Greenland
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Russian Arctic
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Franz Josef Land (1)
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New Siberian Islands (1)
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Severnaya Zemlya (1)
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Asia
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Arabian Peninsula
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Oman (1)
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Far East
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China
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Nanpanjiang Basin (1)
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Vietnam (1)
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Himalayas (1)
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Bengal (1)
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Bihar India (2)
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Deccan Plateau (1)
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Jharkhand India
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Maharashtra India
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Jammu and Kashmir (1)
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Pakistan (1)
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Irkutsk Russian Federation (2)
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Krasnoyarsk Russian Federation
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Norilsk region (4)
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Kuznetsk Basin (3)
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Lower Tunguska River (2)
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Siberia (10)
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Aldan Shield (3)
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Yakutia region (1)
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Stony Tunguska River (1)
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Tunguska Basin (3)
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Tunguska Syneclise (7)
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West Siberia
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Yakutia Russian Federation
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Atlantic Ocean
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carbon
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volcanic rocks
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mid-ocean ridge basalts (2)
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ocean-island basalts (1)
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tholeiite (1)
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tholeiitic basalt (3)
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stable isotopes
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Nd-144/Nd-143 (4)
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O-18/O-16 (1)
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Pb-207/Pb-204 (1)
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Pb-207/Pb-206 (1)
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Pb-208/Pb-206 (1)
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lower Mesozoic (1)
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Permian-Triassic boundary (12)
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metal ores
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metals
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alkaline earth metals
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Sr-87/Sr-86 (6)
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Pb-207/Pb-204 (1)
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Pb-208/Pb-206 (1)
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niobium (1)
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neodymium
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silver (1)
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metamorphic rocks
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oil and gas fields (1)
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Silurian
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Llandovery
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Red Sea region (1)
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GeoRef Categories
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Availability
trap rocks
Evaluating reservoir properties and seal capacities of volcaniclastic rocks for hydrocarbon containment and their application to CO 2 storage Available to Purchase
Abstract Volcaniclastic rocks are commonly overlooked as reservoirs or seals in hydrocarbon plays because their compositions are variably unstable and reactive during burial diagenesis. This study investigated the petrography and petrophysical characteristics of 60 volcaniclastic and four siliciclastic samples from three Paleogene volcanic provinces – East Greenland, Faroe Islands and Ethiopia. The volcaniclastic samples have highly variable helium porosities (average 25.2%), but negligible total optical porosities (average 1.9%), implying reduced reservoir potential. The samples have, however, highly variable air permeabilities (average 11 mD), suggesting that they could make tight reservoirs. The permeabilities are related to either early calcite cements or the devitrification of volcanic glass. Mercury injection capillary pressure data were collected for a subset of 33 samples that at leakage/breakthrough saturations could, under near-surface conditions, hold oil column heights of between 4 and 1181 m (average 240 m). The best seals consistently have zeolite contents of >20 vol% owing to their small pore throat radii. Conversely, the worst seals are dominated by smectite and a conspicuous absence of zeolite minerals. The zeolite-rich volcaniclastic rocks could, therefore, make good shallow seals. These features also apply to CO 2 storage, but questions remain about the reactivity of the volcanic material and secondary minerals with injected CO 2 , but also the adsorbent properties of zeolites, particularly clinoptilolite, in the presence of CO 2 .
The Corrugated Hills Continental Flood Basalt: a c. 2.17 Ga flood basalt province related to breakup of the Superior craton Available to Purchase
Abstract This study documents a major continental flood basalt province in the central Labrador Trough that produced voluminous mafic magmatism along the palaeo-rifted margin of the Superior craton. This area, representing a preserved magma volume of approximately 25 000 km 3 , is characterized by classic ‘traps’ topography with columnar-jointed flows and sills separated by thin clastic sedimentary layers. A gabbroic sill near the bottom of the sequence yielded a U–Pb zircon age of 2166 ± 4 Ma, and another near the middle of the sequence yielded a 2171 ± 3 Ma U–Pb zircon age. These ages overlap in time with published ages of mafic dyke swarms that radiate outwards into the adjacent Superior craton, namely the Biscotasing (2172–2167 Ma) and Payne River (2170–2160 Ma) dykes, as well as the Otish sills (2172–2162 Ma) and Tasiataq (2170 Ma) dyke. Our data suggest that these central Labrador magmas, named the Corrugated Hills Continental Flood Basalt, were emplaced near or above a mantle plume head, leading to thermal uplift and then rifting of the Superior craton margin. Field relationships suggest that these magmas were erupted through thinned Archean crust as a rift-related continental flood basalt suite. The Corrugated Hills Continental Flood Basalt province represents remnants of one of the oldest continental flood basalt provinces on Earth.
Petrology of the Kureika Graphite Deposit in the Roof of the First-Rapid Trap Intrusion (Siberian Platform) Available to Purchase
Olivine in picrites from continental flood basalt provinces classified using machine learning Available to Purchase
Low Geomagnetic Field Paleointensity on the Permian–Triassic Boundary from Study of the Kuznetsk Basin Traps (Southern Siberia) Open Access
Vendian Hydrogeochemistry of the Siberian Platform Available to Purchase
The Influence of Trap Magmatism on the Geochemical Composition of Brines of Petroliferous Deposits in the Western Areas of the Kureika Syneclise (Siberian Platform) Available to Purchase
A COMPARISON BETWEEN ‘PART OF SCOTLAND’ ON WILLIAM SMITH’S MAPS AND CONTEMPORARY MAPS OF SCOTLAND BY LOUIS-ALBERT NECKER AND JEAN-FRANÇOIS BERGER Available to Purchase
Dynamics of Metasomatic Transformation of the Rocks of the Lithospheric Mantle and Earth’s Crust in Deep-Fault Zones Controlling the Siberian Platform Trap Magmatism Available to Purchase
High-Grade Contact Metamorphism in the Kochumdek River Valley (Podkamennaya Tunguska Basin, East Siberia): Evidence for Magma Flow Available to Purchase
Reconstruction of Magma Flow in Permo–Triassic Intrusions of the Angara–Taseeva Syneclise (Siberian Platform) Based on Magnetic Susceptibility Anisotropy Data Available to Purchase
Paleomagnetism of traps of the Franz Josef Land Archipelago Available to Purchase
Modeling of the formation of nonisothermal zoning in magnesian skarns in the ore-magmatic fluid systems of intrusive traps of the southern Siberian Platform Available to Purchase
Geologic prerequisites for high petroleum potential of the northern Siberian Platform Available to Purchase
Lithology, organic geochemistry, and petroleum potential of the northern areas of the Kureika syneclise Available to Purchase
Comparison among Ethiopia-Yemen, Deccan, and Karoo continental flood basalts of central Gondwana: Insights on lithosphere versus asthenosphere contributions in compositionally zoned magmatic provinces Available to Purchase
ABSTRACT In this paper, we present a comprehensive review of literature data (~2600 analyses), including major and trace elements and Sr-Nd isotopes, on continental flood basalts from the Ethiopia-Yemen, Deccan (India), and Karoo (southern Africa) volcanic provinces in order to evaluate whether they can be attributable to similar tectonomagmatic processes that occurred during the past 200 m.y. in central Gondwana. Results indicate that the three investigated provinces share fundamental features, such as the following: (1) Major and trace element compositions are closely comparable, in terms of parental magmas and fractionation trends, for the various continental flood basalt suites recognized in the provinces, namely, low Ti (LT, TiO 2 0.5–3 wt%), high Ti (HT1, TiO 2 1–4 wt%), and very high Ti (HT2, TiO 2 2.5–7 wt%). (2) There is a clear zonal arrangement of continental flood basalts, with the hottest (potential temperature T p up to ~1600 °C) and deepest (up to 5 GPa) HT picrite-basalt magmas in the central area and cooler and shallower LT basalts (T p down to 1450 °C, pressure [ P ] = 2–3 GPa) at the periphery, corresponding to a maximum thermal difference of 60–110 °C from the inner to the outer zones in each province. This conforms to continental flood basalt generation from a lenticular melting region, plausibly reflecting thermo-compositionally zoned plume heads, with maximum excess temperature T ex = 250–300 °C with respect to the notional mid-ocean-ridge basalt (MORB) ambient mantle. (3) The central area of all provinces is characterized by the nearly exclusive occurrence of superheated HT picrite-basalt (and nearly coeval alkaline-carbonatite complexes) at the intersection of multiple extensional lineaments (faulting, rifting, and dike swarms), reflecting the focus of the tectonomagmatic activities. (4) The common occurrence of rhyolitic differentiates at the top of picrite-basalt lavas (e.g., Lalibela suite, northern Ethiopia; Pavagadh suite, Deccan; Lebombo suite, African Karoo) has to be considered an effect of the inversion of the stress regime, from generalized regional extension (continental flood basalt eruption) to localized continental rifting accompanying magma differentiation to rhyolites; activity at some of these rift and dike systems, e.g., the Western Afar Escarpment, the coastal dikes of Western Deccan, and the Rooi Rand dikes, was protracted until continental breakup and the opening of new oceanic branches of the Red Sea, the central Indian Ocean, and southwestern Indian Ocean, respectively. (5) The Sr-Nd isotope distributions of continental flood basalts show HT picrite-basalt magmas mostly recording mantle values unaffected by continental lithospheric signatures, and LT basalts mainly reflecting either mixed source components located at the lithosphere-asthenosphere transition or continental crust contamination, particularly in the Karoo and Deccan provinces. Overall, results from this review provide compelling evidence that hot mantle plumes impinged diachronously on the central Gondwana lithosphere, causing similar tectonomagmatic events and continental flood basalt zonal arrangements that reflect a common thermocompositional zonation of the plume head in the three investigated provinces.