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61.
银坑山铀矿点位于赣南九龙嶂火山盆地南东边缘,矿体呈脉状,水云母化、赤铁矿化明显.与围岩相比,矿石的Al2O3、SiO2含量降低,Fe2O3(FeO)、MnO、CaO、S、Cl呈富集趋势,Mo、Ag、Th为主要伴生组分.从矿化蚀变组合特征看,银坑山矿点属岩浆热液型,且位于岩浆热液成矿系统的上部,深部具成矿前景. 相似文献
62.
《China Geology》2020,3(4):511-523
Natural gas hydrate, oil and gas were all found together in the Qilian Mountain permafrost area, northeast of Qinghai-Tibet Plateau, China. They are closely associated with each other in space, but whether they are in any genetic relations are unknown yet. In this paper, a hydrocarbon gas-generation series, gas-fluid migration series and hydrocarbon gas-accumulation series are analyzed to probe the spatial, temporal and genetic relationships among natural natural gas hydrate, oil and gas. The subsequent results show that natural gas hydrate, oil and gas actually form a natural gas hydrate-oil-gas system. Based on the Middle Jurassic and the Upper Triassic hydrocarbon gas-generation series, it is divided into four major sub-systems in the study area: (1) A conventional Upper Triassic gas-bearing sub-system with peak hydrocarbon gas-generation in the late Middle Jurassic; (2) a conventional Middle Jurassic oil-bearing sub-system with low to mature hydrocarbon gas-generation in the late Middle Jurassic; (3) a natural gas hydrate sub-system with main gas source from the Upper Triassic gas-bearing sub-system and minor gas source from the Middle Jurassic oil-bearing sub-system as well as little gas source from the Middle Jurassic coal-bed gas and the microbial gas; (4) a shallower gas sub-system with microbial alteration of the main gas source from the Upper Triassic gas-bearing sub-system. This natural gas hydrate-oil-gas system and its sub-systems are not only theoretical but also practical, and thus they will play an important role in the further exploration of natural gas hydrate, oil and gas, even other energy resources in the study area. 相似文献
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针对湘中地区邵阳凹陷二叠系龙潭组页岩气资源评价,部署了页岩气调查井2015H-D3井,通过现场解析气等相关样品测试定量分析了页岩含气性特征及其影响因素,并借助气体稳定碳、氢同位素对气体成因进行了初步探讨.结果显示:钻深从150m处开始出现气显,随深度增加,解析气含量呈现先逐渐增大后减小的趋势,300~425m为最高含气层段,累计厚度达125m,现场解析气含量全部大于0.5m^3/t,最高为2.35m^3/t,平均1m^3/t,证实龙潭组具良好页岩气资源潜力.当埋深大于300m时,解析气含量受有机碳含量控制,而埋深小于300m时,解析气含量并不简单受控于有机碳含量,而是受到保存条件的严重制约.气体碳、氢同位素测试显示δ13C1介于-29.87‰~-36.82‰,平均为-34.52‰,δ13C_2介于-29.45‰~-31.02‰,平均为-30.09‰,δD1介于-131.20‰~-178.40‰,平均为-167.40‰.气体成因分析揭示龙潭组页岩气属热成因中的油型气类型.基于沉积现象判断龙潭组为海陆过渡相环境,与氢同位素判断结果基本吻合,但目前还无法确定具体判定区间. 相似文献
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Natural disasters like floods, tornadoes, tropicalcyclones, heat and cold wavewreak havoc and cause tremendous loss ofproperty all over the world. Most ofthe natural disasters are either dueto weather or are triggered due toweather related processes.Extreme weather events claimed thousands oflives and caused damage on vastscale. Recent super cyclone which affectedOrissa in 1999, Bangladesh cyclone of1970 and Hurricane Andrew in 1992 areexamples of some of the more damagingtropical cyclones which affected developingas well as the developed world. Heatand cold waves are also extreme events,which cause enormous losses in terms oflives lost and human discomfort and ailmentsarising out of them. The heat waveof 1995 and 1998 are still fresh in the mindof the Indian public. The estimated lossof human lives due to heat wave in 1998 was morethan 15,000. Economic losses asa result of these disasters and in particular inassociation with tropical cyclones haveincreased enormously over the last three decades.During 1961–1991, total loss oflives from drought alone was 1,333,728 overthe whole world. In terms of economiclosses, there is 8–10 fold increase from thebase figure of 1960. The socio-economicimpact of natural disaster is complex dependingupon the vulnerability of the placeand mitigation strategies that are put in place.Meteorology plays a crucial role in forewarningpeople about the severe/extremeweather systems and a constant endeavour by themeteorological services worldover has gone a long way towards minimizing thelosses caused by natural disasters.The paper summarises the natural disasterstatistics over south Asia and the possibleprediction strategies for combating theirsocio-economic impacts. 相似文献
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农坪金矿床地质特征及成因类型 总被引:6,自引:0,他引:6
农坪金矿床产于下古生界五道沟群与燕山期英云闪长(斑)岩接触带英云闪长(斑)岩体内。矿化类型为含金硅化蚀变岩型,矿体受NW、NE向断裂及裂隙构造控制,矿床成因类型为次火山热液型。 相似文献
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