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161.
东海陆坡及邻近槽底天然气水合物成藏条件分析及前景 总被引:3,自引:1,他引:2
在西太平洋边缘海中,东海是唯一没有获得天然气水合物样品的边缘海。利用已有的地震资料、海底温度资料等,从沉积物来源、沉积地层厚度、烃源岩条件、沉积速率、海底温度—压力条件等方面对东海水合物成藏条件进行了分析。认为冲绳海槽沉积物源丰富,沉积厚度大,且发育烃源岩地层。冲绳海槽较高的沉积速率主要分布于冲绳海槽槽底沉积中心,以及西部陆坡连接海底峡谷底部的三角洲区域。根据冲绳海槽实测的海底温度数据,整个冲绳海槽地区600m以深的范围都能够满足水合物发育的温度、压力条件。以温度梯度为30℃/km计算,冲绳海槽中水合物稳定域的最大厚度为650m。冲绳海槽盆地中普遍发育的底辟构造、背斜构造等局部构造,以及网格状断裂系统,为烃类气流体的向上及侧向运移创造了有利条件,成为天然气水合物发育的有利区带。根据已经发现的BSR特征来看,东海地区天然气水合物前景广阔。 相似文献
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165.
准噶尔盆地西北缘八二区三叠系克下组沉积相研究 总被引:4,自引:0,他引:4
依据沉积学基本理论和方法,综合运用露头、钻/测井及地震资料,对准噶尔盆地西北缘克百地区八二区三叠系克下组进行了沉积相研究.统计了西北缘八二区84口井克下组砂体厚度和砂砾岩含量,在此基础上编制了克下组S7和S6砂组的砂砾岩等厚图和砂砾岩含量等值线图,结合取心井岩心观察,编制了相应的沉积相平面展布图.通过本次研究认为,S7砂组是克下组砂体最发育的层位,也是最主要的勘探目的层.工区主要有2个物源方向,即西北方向和正北方向,均受南白碱滩断裂控制.研究区克下组主要发育的沉积相类型为辫状河、辫状河三角洲和湖泊. 相似文献
166.
辽宁东五家子金矿的矿脉由蚀变岩和石英脉透镜体构成,可采矿体均为硫化物石英脉型.工业矿脉中,石英为烟灰色,发育他形、半自形的细粒黄铁矿等硫化物,有较大规模的矿体.矿化脉中,石英为乳白色,发育粗粒、自形的浅色黄铁矿,无可采矿体.在工业矿脉、次要矿脉、矿化脉的蚀变岩和石英脉样品中,Au,Hg与其他元素的相关性有明显区别.用石英脉样品的As-Ni-Ba图解和蚀变岩样品的Au-Ag-Ba图解预测,矿区外围的西沟1号脉和西沟3号脉属于工业矿脉. 相似文献
167.
168.
Benthic nutrient fluxes in the intertidal flat within the Changjiang (Yangtze River) Estuary 总被引:1,自引:0,他引:1
GAO Lei LI Daoji WANG Yanming YU Lihua KONG Dingjiang LI Mei LI Yun and FANG Tao State Key Laboratory of Marine Geology Tongji University Shanghai China State Key Laboratory of Estuarine Coastal Research East China Normal University Shanghai China 《中国地球化学学报》2008,27(1):58-71
In an annual cycle from March 2005 to February 2006, benthic nutrient fluxes were measured monthly in the Dongtan intertidal flat within the Changjiang (Yangtze River) Estuary. Except for NH4^+, there always showed high fluxes from overlying water into sediment for other four nutrients. Sediments in the high and middle marshes, covered with halophyte and consisting of macrofauna, demonstrated more capabilities of assimilating nutrients from overlying water than the low marsh. Sampling seasons and nutrient concentrations in the overlying water could both exert significant effects on these fluxes. Additionally, according to the model provided by previous study, denitrification rates, that utilizing NO3- transported from overlying water (Dw) in Dongtan sediments, were estimated to be from -16 to 193 μmol·h^-1·m^-2 with an average value of 63 μmol·h^-1·m^-2 (n=18). These estimated values are still underestimates of the in-situ rates owing to the lack of consideration of DN, i.e., denitrification supported by the local NO3^- production via nitrification. 相似文献
169.
Treatment with metallic copper for the removal of elemental sulfur from bitumen extracted from sedimentary rocks or petroleum is the most widely used method. Little attention has been paid, however, to its disadvantages. It was observed that copper can interact with some polar organic substances during conventional sulfur removal, which can strongly influence the quantitative and qualitative determination of bitumen, as has been confirmed by interaction of long-chain fatty acids with copper. The copper soap generated was analyzed by element analysis, inductively coupled plasma optical emission spectrometry (ICP-OES), thermal analysis (TG-DSC) and Fourier Transform Infrared spectroscopy (FFIR). Mechanism of the interaction was investigated and elucidated. Our experimental results would necessitate improvement of the present method for sulfur removal and/or a search for a new one. 相似文献
170.
The Central Tianshan belt in northwestern China is a small Precambrian block located in the southern part of the Central Asia Orogenic Belt (CAOB), which is considered as "the most voluminous block of young continental crust in the world" that comprises numerous small continental blocks separated by Paleozoic magmatic arcs. The Precambrian basement of the central Tianshan Mountains is composed of volcanic rocks and associated volcano-sedimentary rocks that were intruded by granitic plutons. Geochemical analyses demonstrate that the granitic plutons and volcanic rocks were generated in the Andean-type active continental arc environment like today's Chile, and the zircon U-Pb SHRIMP dating indicates that they were developed at about 956 Ma, possibly corresponding to the subduction of the inferred Mozambique Ocean under the Baltic-African super-continent. 相似文献