The Soviet army in Kabul, Afghanistan, on Dec. 31, 1979. Francois Lochon/Gamma-Rapho/Getty Images. The collapse of the Afghan government and the Taliban's recapture of power came after a blitz by ...Web
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New geochemical and geochronological data lead to a fuller understanding of different aspects of the Rajmahal flood basalt province. Earlier work was on surface Rajmahal flows as well as from the nearby Bengal Traps. Samples from a ~300 m borehole near the northwestern corner of the Rajmahal lavas, analyzed herein, reveal the …Web
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In general, vesicular basalts in acquisition and core of three-dimensional CT data, using different materials to ray absorption attenuation coefficient of inconsistency, ... sedimentary phase and tectonic stress analysis of the Meso-Cenozoic sedimentary strata of the Tajik Basin and the Afghan Massif on the western side of the Pamir, and found ...Web
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Afghanistan, a mountainous territory nestled in the heartland of Asia, has long been a battlefield of global powers. But it has never been conquered, and hence …Web
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The associations between flood basalts and the recurrent separation of the Indian plate from Gondwana are assessed. ... overthrusting onto the Campanian sedimentary unit constraints the onset of the collision between the Indian plate and Afghan block to the Late Cretaceous. The subsequent obduction of combined …Web
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Support Afghanistan institutions and personnel in the soil departments to produce and maintain updated soil information; Show the location and type of soil and …Web
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Large olistoliths of intra-plate alkali basalts of hotspot affinity (Sawada et al. 1993; Siddiqui et al. 1994) are found within the hyaloclastite in the Muslim Bagh area ... Boulin J (1981) Structure d Afghanistan sutures periindiennes et Tethys orientale. CR Academy of Sci Paris Ser D 292:239–242. Google Scholar Boulin J (1988) Hercynian and ...Web
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Basalt (/bəˈsɔːlt, ˈbæsɒlt, -sɔːlt/) is a mafic extrusive igneous rock formed from the rapid cooling of magnesium-rich and iron-rich lava exposed at or very near the surface of a terrestrial planet or a moon. More than 90% of all volcanic rock on Earth is basalt. Basalt lava has a low viscosity, due to its low silica content, resulting in rapid lava flows that can …Web
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Anorthite megacrysts are common in basalts from the Japanese Island Arc, and signally rare in other global fields. These anorthites are 1 to 3 cm in size and often contain several corroded Mg-olivine inclusions. The megacrysts generally range from An 94 Ab 4 Ot 2 to An 89 Ab 6 Ot 5 (Ot: other minor end-members, including CaFeSi 3 O 8, …Web
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The basalts show general trends of increasing incompatible elements (K 2 O, Nb, Y, Sr and Yb), and decreasing contents of compatible elements (Cr, Ni, Sc and Ca) with decreasing Mg no. Furthermore, TiO 2, P 2 O 5, LREE and Th define maxima at about Mg no.=56, suggesting late fractionation of Fe–Ti oxides and apatite.Web
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Basalt is the dark, heavy volcanic rock that makes up most of the world's oceanic crust. Some of it erupts on land, too, but to a first approximation, basalt is an oceanic rock. Compared to the familiar granite of the continents, basalt ("ba-SALT") is darker, denser and finer grained. It's dark and dense because it's richer in the dark, …Web
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Babrak Karmal is installed as Afghanistan's Soviet-backed ruler. Groups of guerrilla fighters known as mujahideen or holy warriors mount opposition and a jihad …Web
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In the plot of Th/Yb versus Ta/Yb for discriminating tectonic setting of basaltic rocks 77, all samples plot in the array of basalts from non-subduction settings (e.g., MORB, and within plate ...Web
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River basalts of the northwestern United States. Basalts also occur abundantly on the moon and on the inner planets, including Mars. Basalts are dis- cussed in all textbooks on igneous rocks (e.g., Williams et al., 1982; Philpotts, 1990). Basalts can be classified into two broad types- tholeiite and alkali-based on their chemical char-Web
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Postrifting thermal subsidence led to the deposition of Upper Triassic marine carbonate rocks which unconformably overlie the rift basalts. A similar tectonic history in central Afghanistan suggests continuity between the two regions prior …Web
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In Flood Basalts of Asia (eds Sheth, HC and Vanderkluysen, L), pp. 146 –66. Journal of Asian Earth Sciences 84.Google Scholar. Duraiswami, RA, Sheth, H, Gadpallu, P, Youbi, N and Chellai, H (2020) A simple recipe for red bole formation in continental flood basalt provinces: weathering of flow-top and flow-bottom breccias.Web
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A post-rift Aptian magmatism is recorded in a 500-m-thick sequence of basalts interbedded with marls in the Bacalhau oil and gas field in Santos Basin, SE Brazil. This magmatic section is within the so-called pre-salt sequence of Santos Basin that comprises the major oil and gas reserves of Brazil. This is the first publication of …Web
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Comparison with the different types of OIB indicates that the basalts may be derived from a high U/Pb (HIMU) source with slightly elevated K and Ba contents. The basalts show general trends of increasing incompatible elements (K 2 O, Nb, Y, Sr and Yb), and decreasing contents of compatible elements (Cr, Ni, Sc and Ca) with decreasing Mg no.Web
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Postrifting thermal subsidence led to the deposition of Upper Triassic marine carbonate rocks which unconformably overlie the rift basalts. A similar tectonic history in central …Web
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LREE-enriched komatiitic basalts are commonly found in association with LREE-depleted komatiites. This association is found in a sequence of late Archaean lavas from Newton Township, Ontario. The komatiitic lavas at Newton Township differ from most late Archaean examples in that both the komatiites and the komatiitic basalts are …Web
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A geochemical study was undertaken on basaltic lava flows intercalated with Oligocene to Miocene strata in the Sabzevar region, northern Iran, to examine their petrogenesis in a regional tectonic framework. The lavas are either aphyric or have phenocrysts and micro-phenocrysts of olivine and, to a lesser extent, clinopyroxene. …Web
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Experimental studies at 1 bar and up to 30 kbar establish the crystallization sequences for basalts 12021, 12065, 12022, 12009 and 12040. Olivine is the liquidus phase at low pressures, with minor chromium spinel and pigeonitic clinopyroxene joining the olivine at lower temperatures or accompanying the olivine in the less magnesian basalts (12021, …Web
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A powerful earthquake has killed at least 1,000 people and injured 1,500 in eastern Afghanistan, an official of the ruling Taliban told the BBC. The Taliban appealed for international help for the ...Web
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Basalt rock is made from volcanos, as it forms from lava that rapidly cools above the surface. Basalt is a type of extrusive igneous rock that gets its dark color from the composition of its ...Web
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The Cenozoic intraplate volcanism in northeast China is located more than 1,000 km westward of the Japan Trench 1, while the young alkaline basalts (0–6 Ma) known as petit-spots outcrop up to ...Web
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Mg# values in basalts (from either the volcanic sequence or sheeted dyke, or individual dykes) range from 70.5 to 49.5 (average is 58) suggesting that most of these basalts likely represent melts at a low to moderate degrees of magmatic fractionation, whereas relatively primitive basalts are subordinate.Web
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The Madagascar Cretaceous igneous province exposed in the Mahajanga basin is represented by basalt and basaltic andesite lavas. New 40 Ar– 39 Ar plateau ages (92.3 ± 2.0 Ma and 91.5 ± 1.3 Ma) indicate that the magmatism in the Mahajanga basin started about 92 Ma ago. Four geochemically distinct magma types (Groups A–D) are …Web
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Basalts are usually dark colored, i.e., dark gray, brown-black, greenish-black, or black fine-grained rocks. However, they can have other textures and colors. Also, weathered hand specimens may have a tan, yellow, brown, or reddish-brown surface. Thus, try to get one with a freshly cut surface. 1. ColorsWeb
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These mafic rocks comprise pillow basalts characterized by a vesicular structure. The mid-ocean ridge basalt (MORB)-normalized trace element patterns of basalts from the study area display ...Web
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Basalts that fractionated plagioclase, ... Afghanistan moved in pair with Iran after 290 Ma 12,16,19,66, Sibumasu moved in pair with Qiantang after 289 Ma 67,70,71,72.Web
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