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361.
Oxygen Isotope Exchange Kinetics Between Coexisting Minerals and Water in the Aral Granite Pluton of the Altay Mountains, Northern Xinjiang 总被引:2,自引:0,他引:2
Liu Wei Research Center of Mineral Resources Exploration Chinese Academy of Sciences Chinese Academy of Sciences BeijingHe Baichu Changsha Institute of Geotectonics Chinese Academy of Sciences Changsh Hunanand Chen ZhenshengYichang Institute of Geology Mineral Resources Chinese Academy of GeologicalSciences Yichang Hubei 《《地质学报》英文版》1996,70(4)
Coexisting quartz, feldspar and biotite vary widely in their δ18O values and display a remarkable 18O/16O disequilibrium relation; especially, a quartz-feldspar reversal (△ 18OQUartz_feldspar< 0) exsists in the Aral granite pluton of the Altay Mountains, northern Xinjiang. The 18O / 16O exchange reaction definitely occurred between granite and water. Initial δ18O values of the granite and exotic fluid are evaluated by the mass balance consideration. The conventional method of discrimination between various magma derivations simply with δ18O values of either whole rock or separate minerals is misleading and unreliable. Experiments carried out by the authors show that the 18O / 16O exchange reaction is not accompanied by what geologists describe as petrological and mineralogical alteration effect. This decoupling relation implies that exchange reaction occurs at a relatively high temperature during subsolidus-postmagmatic cooling of magmas. The exchange mechanism is mainly diffusion-controlled. It is 相似文献
362.
催化分光光度法测定痕量钛 总被引:2,自引:0,他引:2
催化分光光度法测定痕量钛周之荣1吴伟华东地质学院应化系江西临川344000催化褪色光度法测定钛的报道较少[1],本文研究了痕量Ti(Ⅳ)催化过氧化氢氧化酸性铬蓝K褪色反应的影响因素,建立了测定痕量Ti(Ⅳ)的催化光度法,并用于测定植物及人发中钛。方法... 相似文献
363.
is paper is concerned with the geochemical features of major elements,transition metal elements,large ion lithophile elements,rare-earth elements and Sr isotopes in alkaline-ul-trabasic rocks in the Jijie complex of Lufeng,Yunnan Province,which is located in southern Sichuan-Yunnan rift zone,one of Luoci alkaline-ultrabasic complexes in central Ynnnan,Moreover,its origin pertaining primary magma,magma soure region,fractional crystallization,etc.are also discussed in the present paper. 相似文献
364.
侯渭 《中国地球化学学报》1996,15(2):100-104
The data available show that some Antarctic carbonaceous chondrites are similar to Cl meteorites.Tehy contain a lot of phyllosilicate aggregates and the oxygen isotopic composition of the whole-rock samples is approximate to that of C1 chondrites,so they are named after quasi-C1(Q-C1)chondrites Unlike Cl metcorites,the Q-Cl chondites possess chondrule structrue,and the compositions of hih temperature condensates(chondrule fragments,mineral grains or aggregates)show that the oxygen fugacity varied within a wide range in the surroundings where they were formed,similar to the variation range from E.H.L,LL to C group chondrites.It is inferred that the Q-C1 chondrites could be formed at the edges far from the equator in the whole asteroid region of the solar nebular disk.where the nebula was lower in density and the condensates were lower in accretion velocity,so that the hydration of chon drules and matrix occurred during the late stage of nebular condensation.The discovery of the Q-Cl chondrites and the fact that the earth and other terrestrial planets contain water indicate that at the edges far from the equator in the terrestrial reigion of the solar nebular disk,a large amount of water was incorporated into the lattice of minerals in the condensates as a result of hydration during nebular condensation,and then found its way into the interior parts of the Earth and other terrestrial planets due to accretion. 相似文献
365.
安徽省大别山南部宿松杂岩变质作用研究 总被引:7,自引:13,他引:7
宿松杂岩的变质作用可分为3个阶段:早期、主期和晚期阶段。主期阶段的矿物组合在云母片岩中为石榴石+多硅白云母+石英+磁铁矿±钠云母±绿帘石/黝帘石;在白云母钠长(二长)片岩和片麻岩中为石榴石+多硅白云母+钠长石+石英+绿帘石/黝帘石±冻蓝闪石;在石榴石钠长角闪岩中为石榴石+冻蓝闪石+钠长石+黝帘石+石英±钠云母±金红石/磁铁矿。根据多种地质温压计和变质反应可以推测主期变质条件为:T=520℃~580℃,P=1.2~1.4GPa,地热梯度为12℃/km,相当于高压过渡型。晚期阶段变质条件为:T=460℃~480℃,P=0.6~0.7GPa,为中压绿帘角闪岩相。宿松杂岩的变质条件介于其南部的蓝闪绿片岩相和北部的榴辉岩相之间,三者是扬子板块向华北板块之下俯冲到不同深度的产物。 相似文献
366.
The incidence of lung cancer in the Gejiu area of Yunnan Province ranks the first in the world.The radon level(indoor,soil) was measured in the Gejiu area by the SSNTD method from 1990 to 1996,The result indicates an extensive high-level of indoor radon in that area though U and Th are lower in local limestones,The indoor radon level of houses located in the geologic fault zone is 6 times high that 2km far from the fault zone.The reason probably is that the radon level of soil in the fault is 6-8 times high that 1 km far from the faults.our data indicate that a lower range of radon levels,0-100Bq.m^-3,exists in healthy families.However,a higher radon level,over 800 Bq.m^-3,is often found corresponding to that of cancer patients‘ homes(the house-owners are suffering from either lung cancer or leukaemia or liver cancer),Obviously,an increase in lung cancer incidence follows an increase in indoor radon level,The risk of cancer induced by indoor radon is no longer an inference,but a fact. 相似文献
367.
大长沙火山岩盆地铀成矿条件分析 总被引:7,自引:0,他引:7
文章分析了盆地的火山活动、火山岩的地球化学特点和铀矿化特征。认为盆地是塌陷式的,岩浆活动分为两个旋迥,并且不同族迥的岩浆来源深度不同。盆地发育有多期次的矿化蚀变,铀源有地幔铀、基底铀及盖层蚀变而迁移出的活化铀。盆地断裂构造发育,有较好的矿质沉淀场所,又处在有利的铀成矿区域背景之下,因此具有较大的铀成矿远景。 相似文献
368.
新疆伊犁盆地侏罗纪煤岩特征及煤相 总被引:2,自引:1,他引:2
应用煤岩学方法,探讨了新疆伊犁盆地侏罗纪煤的煤岩特征及煤相划分,将煤相划分为9种类型即干燥森林沼泽相,潮湿森林沼泽相,草木混生型沼泽相或芦苇沼炭沼泽相。通过煤相分析,为伊犁盆地成煤环境的研究提供了佐证。 相似文献
369.
相山铀矿田成矿作用的地球化学模拟 总被引:4,自引:0,他引:4
相山铀矿田是我国最大的火山岩型热液铀矿田,在地质地球化学和高温高压实研究的基础上,利用地球化学模式程序EQ3/6模拟了成矿热水溶液的形成过程和减压排泄区铀成矿作用。计算机模拟结果表明,通过大气降水与碎斑熔岩相互作用,可以形成富含F和SiO2等矿化剂的含铀热水溶液;由于铀以UO2F^3和UO2(CO3(^2-3等配合形式存在,非常稳定,即使在深部强还原环境中仍能能够迁移;酸性和碱性环境,尤其是强酸性 相似文献
370.