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湖北铜绿山矿床石英闪长岩的矿物学及Sr-Nd-Pb同位素特征   总被引:3,自引:8,他引:3  
铜绿山是长江中下游鄂东南矿集区最重要的、大型夕卡岩型Cu-Fe(Au)矿床。本文对该矿区中与成矿密切的石英闪长岩进行了详细的矿物成分、地球化学及Sr-Nd-Pb同位素研究。结果表明:岩石中斜长石主要为更长石(An=21~31);角闪石贫Ti(0.2),高Mg/(Mg+Fe)(0.5),属于富镁角闪石;而黑云母为镁质黑云母。岩石的地球化学具有高硅(58.86%~67.71%),富碱(Na2O+K2O=5.67%~9.63%),富集轻稀土元素(LREE)和大离子亲石元素(LILE),并强亏损元素Nb、Ta、Ti等特征。岩石的(87Sr/86Sr)i为0.7055~0.7069,εNd(t)为-7.65~-3.44;(206Pb/204Pb)i=17.66~18.00,(207Pb/204Pb)i=15.49~15.56,(208Pb/204Pb)i=37.73~38.19。矿物成分、地球化学和同位素特征说明,铜绿山岩体与阳新岩体为同源岩浆的产物,源区为深度大于40km的富集地幔,经下地壳的混染及分离结晶作用形成。岩浆熔体形成的温度应大于889℃。角闪石和黑云母的温度计估算岩浆结晶温度分别为650~800℃和500~630℃,黑云母开始结晶温度略低于角闪石结晶结束温度,压力为1.49kbar,对应侵位深度约4.9km。岩浆具有利于Cu、Fe、Au等成矿元素进入熔体的条件,可能与板块俯冲作用相关。  相似文献   
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Cultivated in the Eastern Mediterranean region for millennia, the opium poppy (Papaver somniferum) was profoundly significant in the economies, ecologies, cultures, and diets of the peoples of many towns and villages of rural Anatolia. When the United States compelled Turkey to eradicate cultivation of the plant in the early 1970s in order to diminish the flow of heroin into America, farmers were obliged to deal with not only changes in their incomes but also profound changes in their relationships with the land and the state. Although Turkish officials later allowed production to resume in a highly controlled manner for pharmaceutical purposes, significant socioeconomic and ecological dimensions of Turkey's poppy-growing communities were forever changed. Interviewing now-retired poppy farmers, I employ oral history as my primary source of historical evidence to reconstruct these past ecologies and associated social relationships and to give voice to the informants.  相似文献   
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白云鄂博地区碳酸岩墙及岩墙旁侧石英岩中的包裹体研究   总被引:11,自引:6,他引:11  
倪培  A H RANKIN  周进 《岩石学报》2003,19(2):297-306
白云鄂博的碳酸岩墙中包裹体类型有多子晶包裹体、两相水溶液包裹体、含CO_2三相包裹体和含子晶三相包裹体,岩相学和显微测温结果表明,这些包裹体与国外典型的碳酸岩中的包裹体具有很大程度的一致性,反映了其岩浆成因特点;碳酸岩墙中旁侧的白云鄂博H2石英岩中含有大量的流体包裹体,主要类型为NaCl-H_2O包裹体、CO_2包裹体和H_2O±CO_2±固体的包裹体。包裹体的岩相学、显微测温、阴极发光特征、包裹体成分ICP-MS测定,激光拉曼研究等,揭示出石英岩中的包裹体捕获了来自碳酸岩墙的碳酸岩浆流体,提供了一种不可多得的直接研究碳酸岩流体的手段。  相似文献   
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Historical scholarship in traditional geopolitics often relied on documents authored by states and by other influential actors. Although much work in the subfield of critical geopolitics thus far has addressed imbalances constructed in official, academic, and popular media due to a privileging of such narratives, priority might also be given to unearthing and bringing to light alternative geopolitical perspectives from otherwise marginalized populations. Utilizing the early-1970s case of the United States' first “war on drugs,” this article examines the geopolitics of opium-poppy eradication and its consequences within Turkey. Employing not only archival and secondary sources but also oral histories from now-retired poppy farmers, this study examines the diffusion of U.S. antinarcotics policies into the Anatolian countryside and the enduring impressions that the United States and Turkish government created. In doing so, this research gives voice to those farmers targeted by eradication policies and speaks more broadly to matters of narcotics control, sentiments of anti-Americanism, and notions of democracy in Turkey and the region, past and present.  相似文献   
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