【作者】 罗小蓉；

【导师】 张小莉；

【作者基本信息】 西北大学 ， 固体地球物理， 2010， 硕士

【摘要】 鄂尔多斯盆地西缘奥陶系主要为碳酸盐岩地层,由于储层的非均质性和各向异性,储层的有效识别和评价存在一定的困难,大大增加了油、气勘探的难度。西缘地区下古生界自1986年天池构造的T1井在奥陶系获得日产16.4万方的气流,达到工业标准,其它地区钻探过程中虽有气显示,但未发现达工业气流标准的探井。西缘地区总体勘探程度比较低,尤其是下古生界涉及更少。本论文采用石油地质学、沉积学、固体地球物理学和岩石学等多学科的理论和方法,在录井、岩心分析、物性分析化验、试气等资料进行客观标定的基础上,与测井资料相结合,研究鄂尔多斯西缘奥陶系沉积相特征及储层特征,对储层岩性特征、物性特征、孔隙结构及含气性进行分析,对储层进行综合评价,并对有利储集区进行了预测。研究认为：盆地西缘奥陶系地层发育深水盆地、台地边缘斜坡、台地边缘浅滩、开阔海台地、局限海台地、蒸发台地等沉积相带,其中局限海台地和台地边缘浅滩相是有利的沉积相带。奥陶系有利储层主要分布在下奥陶统桌子山组(相当于马六段)和克里摩里组(相当于马四、马五段),颗粒灰岩和白云岩是主要储集岩。储集空间类型以次生溶蚀孔、洞、缝为主要储集空间,储层受到白云岩化作用影响,在准同生时期部分发育晶间孔,而在深埋藏白云岩化时期交代作用对孔隙空间的扩大起较大作用,同时热流体的参与使溶蚀作用增强,形成溶孔、溶洞,但由于埋藏自生矿物的充填,使孔隙度大大缩小。通过对有利储集岩性的展布特征进行分析,结合气层显示情况,认为中央古隆起及古隆起以西T1井—FD1井区附近范围内为研究区有利储集区。更多还原

【Abstract】 Carbonate rocks are the main of Ordovician formation in the West Margin of the Ordos Basin. It is difficult to effectively distinguish and evaluate reservoir because of its strong heterogeneity and aeolotropy, which result in the difficulty of oil and gas exploration was increased. Since 1986, when the T1 well has produced 16.4×104m3 gas in Ordovician formation lower-paleozoic of Tianchi faults belt, and it reached the Industry Standard. But other regions only have gas showing while drilling, have not to reach Industry Oil and Gas Flow Standard. The total level of exploration is low, especially in the lower-paleozoic.Petroleum geology, sedimentology, solid earth physics, petrology and others are combined for this paper. And the mud logging data, core analysis data, physical properties analysis data, gas testing data are uesd to be the basic data. The characters of Ordovician sedimentary facies and reservoirs are studied with the basic data and logging data. The characters of petrography, physical properties, pore configuration, gas potential were analysised. Last, the reservoir performance was overall evaluated, and the favorable carbonate reservoirs were finded.Results:The western margin Ordovician of Ordos Basin includes the deep-water basin, platform margin slope, platform edge shallow facies, open marine platform facies, restricted oceanic tableland and platform evaporite facies. The restricted oceanic tableland facies and the platform edge shallow facies are the favorable ones.Ordovician reservoir is mainly distributed the Lower Ordovician Series ZhuoZiShan formation (equivalent to Ma6 section) and KeLiMoli formation (the equivalent Ma4 section and Ma5 section), the granular limestone and dolomite are the main reservoir rocks.Type of reservoir space is secondary dissolution pores, holes, fractures as the main reservoir space.The reservoir rocks are effected by dolomitization, partly develop intercrystal pore during the development of quasi-crystals, and during dolomitization of the deep burial, the metasomatism play a greater role in the expansion of the pore space, while the involvement of hydrothermal fluids to enhance the dissolution, the formation of dissolved pore, caverns, but buried authigenic mineral filling, making porosity greatly reduced. By analyzing display features of favorable reservoir rocks and of the gas layers, which show the central paleo-uplift and paleo-uplift to west T1 well-FD 1 well nearby within the favorable reservoir area.更多还原