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981.
This study discussed the division of matrix- and fracture-type shale oils in the Jiyang Depression, and proposed the concept of fracture development coefficient. The fracture development coefficient is defined as the ratio of fault throw to the distance between a shale oil well and the nearest fault. Based on CO2 content, state of water, oil production and logging response of shale oil formations, the classification of shale oils was established, i.e., a fracture-type shale oil well has a fracture development coefficient greater than 0.2, while a matrix-type one has a fracture development coefficient less than 0.2. Furthermore, the key control factors of matrix- and fracture-type shale oil enrichment were analyzed using typical anatomical and statistical methods. For matrix-type shale oil enrichment, these factors are lithofacies, total organic carbon (TOC), shale porosity and abnormal pressure; for fracture-type shale oil enrichment, they are lithofacies, extent of fracture development, and abnormal pressure. This study also first described the differences between matrix- and fracture-type shale oils. The results provide reference for the exploration of terrestrial faulted basins in eastern China.  相似文献   
982.
The Duocaima carbonate-hosted Pb-Zn deposit is a newly found large deposit in the southern area of Qinghai Province.In this paper, the characteristics, genesis, significance to Pb-Zn mineralization of the widely developed breccias, and the ore-forming process have been carefully studied based on geological documentation of drilling holes, microscopic observations of petrography and microstructure and some stable isotope measurements.Based on the compositions of the clast and matrix, the breccias can be classified into three types: limestone clasts cemented by marl; limestone clasts with fine-grained calcareous materials; and limestone clasts cemented by hydrothermal calcite.The mineralization in the first type of breccia is weak, whereas it is strong in the latter two types of breccias.According to the locations of occurrence and structural characteristics of the breccias along with the relationship between the breccias and mineralization, part of the limestone clasts that are cemented by marl and outcrop in the contact zone between the Wudaoliang Formation(Nw) and the underlying Jiushidaoban Formation(Pj) are attributed to synsedimentary fault-genetic breccia, whereas the last of the limestone clasts that are cemented by marl and developed in the Jiushidaoban Formation(Pj) are attributed to the breccia generated by karst cave collapse; the limestone clasts with fine-grained calcareous materials and the limestone clasts cemented by hydrothermal calcite are attributed to breccia formed by hydrothermal dissolution.The breccia formed by karst collapse had consistently evolved for a long period of time, while the breccias with other origins were formed around the period of mineralization(i.e., about or slightly later than 20–16 Ma).The breccia generated by karst cave collapse and hydrothermal dissolution are somewhat related; the formation of the breccia from karst cave collapse provided open space for the later mineralization and reaction between hydrothermal fluids and host rocks, and the subsequent strong dissolution by hydrothermal fluids transformed some of the breccia formed earlier by karst cave collapse.Meanwhile, carbonate host rocks with breccias and brecciaed mineralization can be a potential sign of Mississippi Valley Type(MVT) deposits and important indicators for regional mineral exploration.The δ13CV-PDB, δ18OVSMOW, and 87Sr/86 Sr values of hydrothermal calcite in the Duocaima deposit range from 4.3‰ to 7.1‰, 14.9‰ to 20.1‰, and 0.707494 to 0.708185, respectively; the δ13CV-PDB, δ18OV-SMOW, and 87Sr/86 Sr values of the host limestones of the Jiushidaoban Formation range from 3.6‰ to 5.3‰, 18.0‰ to 20.5‰, and 0.707372 to 0.707945, respectively.The δ13CV-PDB and 87Sr/86 Sr values of hydrothermal calcite and limestone are similar, indicating single sources of C and Sr in this deposit, with the likely source being the limestone of the Jiushidaoban Formation.The minor scattering of the δ18OV-SMOW values suggests that different O isotope fluids underwent the isotope exchange reaction.The C-O-Sr isotope characteristics indicate that the host limestones experienced a dissolution and precipitation process during mineralization, which is beneficial to improving the porosity of host rocks and promoting the precipitation of metal sulfides.The δ34SV-CDT value of the breccia-type mineralization sulfides ranges from-30.4‰ to-0.3‰; that is, the δ34SV-CDT value is negative with considerable variation, illustrating that during the breccia-type mineralization process, the bacteriogenic reduction of sulfates provided the vast majority of sulfur, whereas the thermochemical reduction of sulfates was relatively unimportant.The brecciation that occurred as a result of karst cave collapse was mainly generated by the dissolution of groundwater; however, the brecciation related to hydrothermal dissolution and mineralization processes were caused by mixing of different fluids.  相似文献   
983.
Two new species, Cretolimonia excelsa sp. nov. and Mesotipula gloriosa sp. nov., in Limoniidae of Diptera are described and illustrated, based on three fossil specimens with bodies and complete wings. These specimens were collected from the latest Middle Jurassic Jiulongshan Formation at Daohugou, Inner Mongolia, China. These are the first fossil records of these two genera from China.  相似文献   
984.
<正>Chambersite is a rare mineral worldwide,a manganese chloride borate(Mn3B7O13Cl),which was first discovered in the recovered brine from a salt dome at Chambers,Texas,USA.This rare mineral has been proven to have a great utilization value in anti-nuclear radiation,hightemperature friction materials,medicine and stealth materials,and can be used in aerospace and  相似文献   
985.
干树金矿是河南熊耳山矿集区内的构造蚀变岩型金矿,矿区的金矿体主要赋存在构造蚀变岩带内,且与多阶段的热液活动密切相关。深源的含金成矿流体沿深大断裂向上运移,在温度、压力控制下,在构造的有利部位与围岩发生交代作用,形成多种围岩蚀变和金矿化。其中,硅化、绢云母化、黄铁绢英岩化、钾化与金矿化关系密切;围岩蚀变具有水平分带和垂直分带特征:从中心向两侧,蚀变依次为黄铁绢英岩化→石英绢云母化→钾化→绢云母化→绿泥石化,金品位呈逐步降低的分布规律;从地表向深部,则出现蚀变为褐铁矿化-高岭土化-硅化-碳酸盐化-绢云母化-钾化-黄铁矿化-黄铁绢云岩化,金品位呈由低转高的变化趋势。  相似文献   
986.
<正>There is a general consensus that Plate Tectonics can explain metallogenesis based on the collisions between oceanic and continental crust.For instance,the large-sized porphyry copper deposits that occur along the Cordillera of the Andes around the east coast of the Pacific,and in the Phillipines,Malaysia and Indonesia along the western coast of the Pacific that sit upon the massive Pacific plates.They are considered to be typical of deposits resulting from collision between the oceanic and continental crust.Many experts,however,have long held a negative view about whether the collision between  相似文献   
987.
<正>Hot Dry Rock(HDR)refers to those generally deeply buried impermeable metamorphic or crystallized biotite gneiss,granite and granodiorite rock bodies,with a burial depth greater than 2000 m,containing no water or vapor.HDR is as implied,hot and dry,with temperatures ranging from 150 to 650℃,and it can be utilized as a heat  相似文献   
988.
<正>Geological Brigade 405 of Hunan Provincial Geology and Mineral Exploration and Development Bureau discovered the Danaopo and Yangjiazhai super-large PbZn deposits through 5 years(2009–2014)of exploration in Huayuan County,Hunan Province.These deposits contain208.4942 million tons of(332+333)class Pb+Zn ores and4.8746 million tons of metal amounts,of which metal amounts of 333 class zinc are 4.1198 million tons and metal amounts of lead are 0.7548 million tons,associated with useful components of Cd,Ag and Se.In addition,the Limei,Qingshuitang and Yutang Pb-Zn deposits were  相似文献   
989.
【目的】探求真空微波干燥凡纳滨对虾的最佳工艺条件,以期为开发凡纳滨对虾即食食品提供技术参考。【方法】以新鲜凡纳滨对虾为原料,模糊数学感官评分为主要考察指标,在单因素试验基础上,选择载装量A、功率B、真空度C为自变量,利用响应面法和模糊数学评价法对真空微波干燥工艺进行优化。【结果】以感官评定为基础对真空微波干燥凡纳滨对虾的品质进行权重分析,得到权重集K=(色泽0.335,滋味0.305,香气0.215,组织质地0.145)。建立二次多项回归方程:Y=84.588+1.084A+1.409B+1.700C-7.353A2-8.793B2-13.860C2,显示载装量A、功率B、真空度C对感官评分有极显著影响(P<0.01)。通过响应面分析,得到真空微波干燥凡纳滨对虾的最佳工艺条件:载装量75 g,加热功率400 W,真空度0.08 MPa。在此条件下,真空微波干燥凡纳滨对虾品质良好,感官评分为(85.6±0.07)分,与预测值85.92分误差较小。【结论】响应面法优化凡纳滨对虾真空微波干燥工艺具有操作简单、优化条件精确、结果显示直观等优点;建立的回归方程能反映装载量等三个因素对指标的影响规律,并可进行实际预测。  相似文献   
990.
水资源、能源、粮食安全是实现可持续发展的重要支撑,与可持续发展各目标存在紧密联系。论文基于水—能源—粮食纽带关系(WEF nexus)系统相关的理论、方法与应用等最新研究成果,根据研究对象的时空尺度,考虑系统物质、能量、信息交换,重新解析了WEF nexus系统的定义与组成、内部相互作用过程、输入与输出、影响因素;阐明了气候变化对水、能源、粮食3个子系统及其纽带关系,以及不同类别人类活动对WEF nexus系统的正面和负面影响。进一步分析了水、能源、粮食与可持续发展目标的关联性,以“研究主题—学科理论—技术方法—实践应用”为主线,提出了面向可持续发展的WEF nexus系统研究框架及其3个核心研究内容:WEF nexus系统内部纽带关系和总体状态评估、系统变化的驱动因素识别和系统的外部性影响分析。最后,针对WEF nexus系统跨学科分析的需求,基于纽带关系的理论研究与应用不足的现状、系统时空边界的多样性特点,剖析了多学科交叉与融合研究的具体思路;提出了基于纽带关系的综合性分析指标与计算方法的研究设想;指出了多尺度研究成果耦合应用的必要性和方式。研究可为WEF nexus系统的基础理论...  相似文献   
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