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111.
Double packer equipment for hydraulic test can be used to measure pressure of test zone directly, and it is frequently used to perform many kinds of hydraulic tests and take groundwater sample from borehole. The test method of this equipment mainly includes the test design, implementation, interpretation and synthetic analysis. By adopting the double packer equipment for hydraulic test, the parameter distribution of rock permeability along borehole can be acquired, as well as the connectivity, water conductivity and water bearing capacity of the disclosed structure and the chemical characteristics of the deep groundwater. It is a necessary method for the research and evaluation of the complex hypotonicity terrace site selection under geological conditions. This method is not only suitable for the geological disposal of high level radioactive waste, but also can be used in the site selection of underground facilities such as storage of petroleum and carbon dioxide. Meanwhile, it has a good application prospect in other hydrogeological investigation fields.  相似文献   
112.
Late Jurassic organic-rich shales from Shabwah sub-basin of western Yemen were analysed based on a combined investigations of organic geochemistry and petrology to define the origin, type of organic matter and the paleoenvironment conditions during deposition. The organic-rich shales have high total sulphur content values in the range of 1.49–4.92 wt. %, and excellent source rock potential is expected based on the high values of TOC (>7%), high extractable organic matter content and hydrocarbon yield exceeding 7000 ppm. The high total sulphur content and its relation with high organic carbon content indicate that the Late Jurassic organic-rich shales of the Shabwah sub-basin were deposited in a marine environment under suboxic-anoxic conditions. This has been evidenced from kerogen microscopy and their biomarker distributions. The kerogen microscopy investigation indicated that the Late Jurassic organic-rich shales contain an abundant liptinitic organic matter (i.e., alginite, structureless (amorphous organic matters)). The presence of alginite with morphology similar to the lamalginite alga and amorphous organic matter in these shale samples, further suggests a marine origin. The biomarker distributions also provide evidence for a major contribution by aquatic algae and microorganisms with a minor terrigenous organic matter input. The biomarkers are characterized by unimodal distribution of n-alkanes, low acyclic isoprenoids compared to normal alkanes, relatively high tricyclic terpanes compared to tetracyclic terpanes, and high proportion of C27 and C29 regular steranes compared to C28 regular sterane. Moreover, the suboxic to anoxic bottom water conditions as evidenced in these Late Jurassic shales is also supported based on relatively low pristane/phytane (Pr/Ph) ratios in the range of 0.80–1.14. Therefore, it is envisaged here that the high content of organic matter (TOC > 7 wt.%) in the analysed Late Jurassic shales is attributed to good organic matter (OM) preservation under suboxic to anoxic bottom water conditions during deposition.  相似文献   
113.
许厂煤矿下组煤中蕴藏着较为丰富的瓦斯、二氧化碳资源。下组煤位于瓦斯风化带内,含瓦斯、二氧化碳和氮气等气体,瓦斯含量与埋藏深度呈正相关关系,主要存在低含量瓦斯、二氧化碳抽采率、二氧化碳资源化转换等技术方面的问题。从国家相关优惠政策、资源优势、煤与煤层气一体化开发技术、近水平长钻孔定向钻进技术、煤层压裂造缝技术、煤层注气增产技术和瓦斯、二氧化碳气体提纯技术等关键技术的发展程度,结合煤矿的下组煤层的开采方案,认为许厂煤矿有着较好的煤炭与瓦斯、二氧化碳一体化开发利用前景。  相似文献   
114.
柴达木盆地北缘侏罗系页岩气地质条件   总被引:1,自引:1,他引:0  
侏罗系泥页岩是柴达木盆地的主力烃源岩之一,具备形成页岩油气的地质条件。对采自柴北缘鱼卡、大煤沟、小煤沟、开源、绿草沟、大头羊等煤矿附近地表露头的11块中侏罗统泥页岩样品进行单样品多参数实验分析,探讨了陆相页岩有机地化、储层物性、含气量等参数之间的关系,建立了页岩气资源评价参数体系。结果表明,柴达木盆地北缘中侏罗世处于浅湖-半深湖湖相沉积,断裂较发育,泥页岩富含有机质,具有低孔、低渗、低熟、较高含气量等特点,具备形成页岩油气的地质条件,进一步的勘查开发需优选地层压力系数高、保存条件较好、脆性矿物含量高的页岩气甜点区。  相似文献   
115.
西藏改则县多不扎地区上侏罗统对望山组的建立及意义   总被引:1,自引:0,他引:1  
董宇超  李才  王明  范建军  吴浩 《地质通报》2016,35(8):1263-1270
对望山组是发育在羌南板块南缘的一套岩石组合,以安山岩、流纹岩、玄武质凝灰岩为主,有少量的玄武安山岩夹层,具有明显的岩浆喷出相和沉积相韵律分布的特点。利用LA-ICP-MS同位素定年技术对对望山组安山岩中的锆石进行了U-Pb同位素测年,获得锆石的~(206)Pb/~(238)U年龄加权平均值为150.5±0.6Ma,表明对望山组的形成时代为晚侏罗世中晚期,在详细剖面测制和区域对比的基础上建立了对望山组。对望山组的建立对完善班公湖-怒江缝合带的地层系统、探讨班公湖-怒江洋的晚侏罗世构造演化具有重要的地质意义。  相似文献   
116.
王贝  李鹏  刘智贤  程龙  闫磊  王卫军 《地质通报》2016,35(9):1479-1487
西藏谢通门县一带区域上属于冈底斯花岗岩带南亚带,侵入岩极其发育,目前填绘有白垩纪、古近纪和新近纪岩体。通过同位素年代学研究,获得12个锆石的U-Pb同位素年龄数据,在原划归白垩纪、古近纪和新近纪岩体中解体出侏罗纪侵入体,按其岩石类型特征,归并为早侏罗世东热村序列和中侏罗世东嘎乡序列。其中,在约拉嘎莫岩体中获得锆石U-Pb同位素年龄166.9±2.8Ma,时代为中侏罗世巴柔期。  相似文献   
117.
Anchiornis huxleyi, which is a member of the Middle–Late Jurassic Yanliao Biota, is the smallest feathered dinosaur ever known. It has been described as a critical link between feathered dinosaurs and birds. Recent studies, including those of Anchiornis, Xiaotingia, Eosinopteryx and Aurornis, challenged Archaeopteryx as the most basal bird. The new Anchiornis huxleyi specimens that are described in this paper show some minor different characters compared to previously reported Anchiornis specimens, which has revised the character list of Anchiornis and indicates a different phylogenetic point from former opinions.  相似文献   
118.
南海北部潮汕坳陷侏罗系具有很大的油气勘探潜力,沉积特征对其储层的发育具有明显的控制作用。通过对研究区最新地震资料精细解释,可以划分出4个典型地震反射界面和3个地震反射层,根据层序界面圈出侏罗系分布特征和残留厚度;通过地震相-沉积相转换对比分析研究,识别出侏罗纪地层不同时期的沉积相类型及其分布特征,重塑了潮汕坳陷侏罗系沉积演化史。该区主要发育5类沉积相、8种沉积亚相,其中滨岸三角洲前缘亚相和深水扇中亚相分别控制了碎屑流砂岩优质储层的发育;此外,浊流砂岩储层主要受控于物源供给的影响,距离三角洲砂体朵叶越近,滑塌浊积体数量越多,面积也越大。总体上,滨岸三角洲前缘亚相、深水扇中亚相和滑塌浊积体是研究区良好的储集相带,该类储集体由于埋藏较深加之被泥岩覆盖,对油气聚集较为有利。  相似文献   
119.
The geological structure and conditions of formation of a Lower Cretaceous clinoform complex in West Siberia are examined based on sequence stratigraphy. The regional Berriasian-Hauterivian clinoforms are interpreted as third-order sequences, and their formation should be considered in terms of the Depositional Sequence III model. Productive beds of both shallow and deep marine as well as continental genesis formed mostly in a regressive basin and belong to the highstand systems tracts.  相似文献   
120.
We discuss the geologic structure of the Berriasian-Lower Aptian deposits of the Gydan Peninsula. Eight seismic sequences have been distinguished; most of them are associated with Lower Cretaceous regional clinoforms of West Siberia, their characteristics are given. A correlation of productive beds was based on the stratotype sections of the Yamal and Gydan Peninsulas as well as seismic and well data. A sequence stratigraphic model of the Berriasian-Lower Aptian complex is proposed.  相似文献   
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