【作者】 程艳清；

【导师】 毛小平；

【作者基本信息】 中国地质大学（北京） ， 矿产普查与勘探， 2010， 硕士

【摘要】 为了进一步扩大二连盆地的勘探领域及提高勘探成功率,本文以二连盆地赛汉塔拉凹陷作为研究区。通过对赛汉塔拉凹陷内部基础地质资料、岩心资料、录井图、地震资料并结合单井相分析及剖面相对比,以沉积学及石油地质学等学科为指导,对研究区内地层、物源、砂体平面展布特征进行了重点研究,分析了研究区内的沉积相特征及展布规律,确定了重点层段的沉积相类型,为下一步的油气勘探提供了一定的依据。地层对比剖面显示出阿尔善组和腾格尔组有着明显的东厚西薄的特点。由于边界断裂锡林断裂的构造活动较强,并且快速下沉,在其断裂中部沉积了巨厚的阿尔善组和腾一段泥岩,为本凹陷的烃源岩打下了坚实的基础。同时锡林断裂的下降盘也沉积了来自东部的多个近裙带状分布的水下扇、湖底扇扇体。加之腾二段、赛汉组沉积时期的沉积物源的丰富,为油气储集提供了良好的条件。沉积相分析上表明,区内发育有扇三角洲平原亚相、扇三角洲前缘亚相、前扇三角洲亚相、湖底扇、湖泊相和辫状河三角洲平原亚相。阿尔善沉积时期湖水范围较小,以滨浅湖为主。晚期西北方向物源充足,以辫状河三角洲沉积为主,南北长轴方向,主要发育以三角洲沉积为主,而在东西的短轴方向,则以水下扇、扇三角洲沉积为主要沉积。在这个时期,湖盆内部和东部陡岸,沉积了厚度较大的湖相暗色泥岩沉积,成为本凹陷的第一套烃源岩层。腾一段沉积时期,以湖相泥岩沉积为主,厚度巨大。而在赛4东洼槽,形成东部物源的大规模扇三角洲前缘沉积,厚度稳定,易于油气的成藏。在湖盆的南北长轴方向,以三角洲沉积为主。腾二段沉积时期西部缓坡带形成规模较大的扇三角洲沉积,东部陡岸主要为近岸水下扇、湖底扇扇体。东部陡坡带的湖底扇与水下扇砂岩体临近烃源岩,易于形成岩性圈闭,对油气勘探具有重要意义。更多还原

【Abstract】 In order to enlarge the exploration field and improve the exploration success rate in Erlian Basin, this thesis used Saihantala Depression of Erlian Basin as a study area. In current thesis, the stratum, source, distribution of sand bodies of Saihantala depression were emphatically studied, then the sedimentary facies and distribution rules were analyzed by collecting and analyzing basic geological data, logging, logging maps, seismic data, single well facies and profile facies comparison under the guidance of sedimentology and petroleum geology, etc. finally, the sedimentary facies of key layers were determined based on frontal results. The results of this thesis will provide certain foundation of oil and gas exploration for the next step.Stratigraphic correlation section showed that Aershan group and Tenggeer group were thicker in east and thiner in west, Due to strong tectonic activity and rapid subsidence of Xilin rupture of boundary fault, very thick Aershan group and Tenggeer group mudstone were deposited, it laid a solid foundation for the source rocks of this depression. At the same time, the thrown side fault deposited multiple waistband-like underwater fan and sublacustrine fan from east, plus plenty sediment source during sedimentary period of Tengger group and Saihantala groupk, It provided a favorable condition for oil and gas reservoir.Sedimentary facies analysis shows that fan-delta plain subfacies, fan-delta front subfacies, front fan-delta subfacies, lacustrine fan, lacustrine facies and braided delta plain subfacies were developed in the research area.During Aershan depositional period, the lake range was rather smaller and shore-shallow lake facies is the main characteristic. At the late phase of Aershan period, the Northwest uplift provided a large number of sedimentary sources for the studied region and the braided river delta was the preferential depositional system, along the north-south long axis trend, mainly developed delta facies, otherwise at the short direction of east-west, underwater fan and fan delta sedimentaries were abroadly deposited. In this period, both at the lake and the east steep shore, it deposited thick dark shale deposition, as the first set of source rocks depression of the depression.During Teng 1 episode, a great thichness of lake mudstone was yielded, at the east Sai 4 trough, forming the large-scale fan delta front deposits of the eastern provence, thickness keep stability through research region and easy-to-oil and gas accumulation. As The long axis of the lake, north to south, donimated by delta deposits.Within Teng 2 episode, large scale fan-delta deposits was formed in the west gentle slope zone, and the steep eastern shore mainly formed subaqueous fan and lacustrine fan.Sandstone body of the lacustrine fan and submarine fan around the east Steep slope closed to the source rock, which easy to form subtle trap and has significant meaning for the oil and gas exploration.更多还原