نتایج جستجو برای: alkali granite
تعداد نتایج: 20054 فیلتر نتایج به سال:
The petrogenesis of aluminous A-type granites is a contentious subject. Here, we focused on the North Kudi pluton in Western Kunlun orogen to investigate origin and magmatic processes responsible for generating granites. Samples from are metaluminous weakly peraluminous. K-feldspar granite samples characterized by high alkali Cl contents, HFSE concentrations FeO/MgO, low F content, negative Ba,...
We describe the Jebel Aja igneous intrusion (JAII), which sits at farthest northeastern edge of exposed Arabian Shield in Saudi Arabia. The JAII consists late Neoproterozoic post-collisional A-type granites, and was emplaced during tectonic extension. It is a composite pluton consisting granitic core (monzogranite, syenogranite alkali feldspar granite) surrounded by later phase alkaline peralka...
Cancer Risk Assessment and Geochemical Features of Granitoids at Nikeiba, Southeastern Desert, Egypt
Different rock types (syenogranite, alkali feldspar granite and quartz syenite intruded by microgranite dikes veins) were investigated in the Nikeiba region Egypt. The main components of studied intrusive rocks, comprised granites syenite, are plagioclase, amphibole, biotite, K-feldspar different proportions. Ground gamma ray measurements show that syenogranite, have highest radioactivity (K, e...
A thin glacial diamicton, informally termed Granite drift, occupies the floor of central Beacon Valley in southern Victoria Land, Antarctica. This drift is ,1.0 m thick and rests with sharp planar contacts on stagnant glacier ice reportedly of Miocene age, older than 8.1 Ma. The age of the ice is based on 40Ar/39Ar analyses of presumed in situ ash-fall deposits that occur within Granite drift. ...
Lying along the south of Mongol–Okhotsk Suture Belt (MOSB) in Horqin Right Middle Banner Inner Mongolia, Chuhuertu granite is exposed Duerji tectonic melange. Based on systematic field geological characteristics, petrology, geochemistry, and zircon U-Pb chronology, we determined petrogenesis pluton setting, provide evidence for dominant factors magmatism study area. LA-ICP-MS dating showed an a...
Occupational exposure to crystalline silica has received renewed attention. The National Conference to Eliminate Silicosis in March 1997, was extensive. The conference included workshops that covered silica exposures and the risks in construction, the mining industry, quarries, and foundries.(1) The Occupational Safety and Health Administration (OSHA) launched a special emphasis program in May ...
decompression to achieve the same result appear to require extreme The Manaslu granite is the most studied of the dozen or so plutons conditions not permitted by available geological constraints. that make up the High Himalayan leucogranite belt. The inferred relationship of the Manaslu granite with important Himalayan tectonic structures has inspired repeated attempts to determine its crystall...
An innovative ultrasensitive technique was used for lead isotopic analysis of individual zircons extracted from granite core samples at depths of 960, 2170, 2900, 3930, and 4310 meters. The results show that lead, a relatively mobile element compared to the nuclear waste-related actinides uranium and thorium, has been highly retained at elevated temperatures (105 degrees to 313 degrees C) under...
Cretaceous represents one of the hottest greenhouse periods in the Earth's history, but some recent studies suggest that small ice caps might be present in non-polar regions during certain periods in the Early Cretaceous. Here we report extremely negative δ(18)O values of -18.12‰ to -13.19‰ for early Aptian hydrothermal zircon from an A-type granite at Baerzhe in northeastern China. Given that ...
The granite stone is the most widely used in the construction and granite slurry is generated through cutting and polishing of the stone. Granite slurry is waste material consisting of very fine powder and creats disposal and environmental problems in worldwide today. Disposal of granite waste leads to health hazards like respiratory and allergy problems to the people around. It also causes the...
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