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排序方式: 共有237条查询结果,搜索用时 343 毫秒
131.
Journal of Oceanology and Limnology - The aim of this study was to test the effects of including sweet potato tuber and stem powder in feed on the body composition and digestive enzyme activities... 相似文献
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134.
K1孔位于罗布泊“耳轮”构造的北缘。磁性地层初步研究得知,在孔深61~62m处为界,以上为布容正向极性时(Br),以下为松山反向极性时(Ma)。在孔底97~100m处的正向极性偏移应属Cobb Mountains事件,对照S.C.Cande和D.V.Kenk修定的古地磁极性年表,氏地层的年代为1.2Ma,归属早更新世中期。中更新世地层厚50余米,晚更新世地层厚10m左右,全新世地层厚度小于5m。根 相似文献
135.
<正>Shallow lacustrine delta front(SLDF)comprises mainly sheetlike subaqueous distributary channels(SDC)formed in shallow,gentle,and tectonically steady slope(Cai and Zhu,2011).SDC proves an important hydrocarbon reservoir type in the Daqing oilfield,Changqing oilfield,and the newly discovered Moxizhuang oilfield in Central Junggar Basin.However,SDC tends to prograde quickly 相似文献
136.
塔里木盆地北部志留系碎屑锆石测年及其地质意义 总被引:3,自引:0,他引:3
志留系是塔里木盆地第一套砂岩储层广泛分布的沉积盖层,其沉积来源与成因对志留纪构造演化及周边造山带的研究具有重要意义。塔里木盆地北部地区2个志留系代表性样品的碎屑锆石LA-ICP-MS U-Pb定年研究表明,志留系具有比较集中的三期物源年龄:中元古代早期1500~1600Ma、新元古代早期750~900Ma、奥陶纪450~500Ma。碎屑锆石定龄表明东部地区志留系物源主要来自阿尔金地区奥陶纪火成岩,而西部塔北地区志留系物源主要来自北部古隆起前寒武纪基底。前寒武纪锆石年龄揭示塔里木板块在新元古代时期与Rodinia超大陆具有相似的聚合与裂解演化史,塔里木北部地区在中元古代存在与Columbia超大陆裂解时间一致的构造-热事件。 相似文献
137.
正Objective Lop Nur is one of the world's largest Quaternary salt lakes and is currently a playa. In this lake, unique giant glauberite deposits occur, of which the intercrystalline pores host super-large liquid potash deposits. Recently, it has been thought that the potassium-rich brine was formed when the enormous quantity of glauberite deposited. To clarify this issue 14 C dating for brine is used to provide new evidence of chronology illustrating the relationship of potassium-rich brine with the host glauberite rock and improve our understanding of the formation mechanism of the brine in Lop Nur playa. 相似文献
138.
在柴达木盆地阿尔金斜坡第三系地层中,砂岩中碳酸盐重结晶强烈、压实程度弱、石英自生加大较弱、早期碳酸盐胶结物发育。碳酸盐主要为无机成因,少量与生物气有关,其含量受盐度的影响。泥岩中粘土矿物以伊利石、绿泥石和伊蒙混层为主,缺少蒙脱石和高岭石,随埋深增加,伊利石相对含量变化无规律可循,绿泥石相对含量减少,推测伊利石主要为陆源成因。 相似文献
139.
电磁资料在柴达木盆地东部地区石炭系勘探中的应用 总被引:1,自引:0,他引:1
以柴达木盆地东部新采集的电磁资料为基础,同时以钻井、地震资料为约束,结合其他勘探资料、重力资料进行柴东地区石炭系综合研究、联合解释。研究过程中,首先对电磁资料进行了前期的预处理和反演,主要采用了一维Bostick反演、一维连续介质反演、二维共轭梯度反演、二维连续介质反演及最优化电性分层等反演技术;而后通过对电磁资料进行联合解释和综合研究,得出了柴达木盆地东部石炭系厚度图、石炭系埋深图等柴东地区综合研究成果;最后利用上述研究成果预测了柴达木盆地东部石炭系含油气有利区带,并且进一步针对柴达木盆地东部石炭系勘探提出了有意义的结论和建议。 相似文献
140.
ZHANG Xu LIU Chenglin LI Bing WU Linqiang GUI Herong WANG Ziling ZHANG Zhihui LIANG Dexiu 《《地质学报》英文版》2020,94(2):337-351
The Songliao Basin is one of the most important petroliferous basins in northern China. With a recent gradual decline in conventional oil production in the basin, the exploration and development of unconventional resources are becoming increasingly urgent. The Qingshankou Formation consists of typical Upper Cretaceous continental strata, and represents a promising and practical replacement resource for shale oil in the Songliao Basin. Previous studies have shown that low-mature to mature Qingshankou shale mainly preserves type Ⅰ and type Ⅱ1 organic matter, with relatively high total organic carbon(TOC) content. It is estimated that there is a great potential to explore for shale oil resources in the Qingshankou Formation in this basin. However, not enough systematic research has been conducted on pore characteristics and their main controlling factors in this lacustrine shale reservoir. In this study, 19 Qingshankou shales from two wells drilled in the study area were tested and analyzed for mineral composition, pore distribution and feature evolution using Xray diffraction(XRD), scanning electron microscopy(SEM), low-pressure nitrogen gas adsorption(N2-GA), and thermal simulation experiments. The XRD results show that clay, quartz, and feldspar are the dominant mineral constituents of Qingshankou shale. The clay minerals are mostly illite/smectite mixed layers with a mean content of 83.5%, followed by illite, chlorite, and kaolinite. There are abundant deposits of clay-rich shale in the Qingshankou Formation in the study area, within which many mineral and organic matter pores were observed using SEM. Mineral pores contribute the most to shale porosity;specifically, clay mineral pores and carbonate pores comprise most of the mineral pores in the shale. Among the three types of organic matter pores, type B is more dominant the other two. Pores with diameters greater than 10 nm supply the main pore volume;most are half-open slits and wedge-shaped pores. The total pore volume had no obvious linear relationship with TOC content, but had some degree of positive correlation with the content of quartz + feldspar and clay minerals respectively. However, it was negatively correlated with carbonate mineral content. The specific surface area of the pores is negatively related to TOC content, average pore diameter, and carbonate mineral content. Moreover, it had a somewhat positive correlation with clay mineral content and no clear linear relationship with the content of quartz + feldspar. With increases in maturity, there was also an increase in the number of carbonate mineral dissolution pores and organic matter pores, average pore diameter, and pore volume, whereas there was a decrease in specific surface area of the pores. Generally, the Qingshankou shale is at a low-mature to mature stage with a TOC content of more than 1.0%, and could be as thick as 250 m in the study area. Pores with diameters of more than 10 nm are well-developed in the shale. This research illustrates that there are favorable conditions for shale oil occurrence and enrichment in the Qingshankou shale in the study area. 相似文献