在主力勘探领域未明确的背景下,探讨桂中地区下石炭统寺门组砂岩储层物源特征,结合野外剖面和钻井薄片、砂地比和砂砾岩厚度分布、重矿物组合、古流向、地震相等资料,研究桂中地区下石炭统寺门组物源体系及沉积相展布规律.结果表明:桂中地区寺门组可分为3个物源组合区,Ⅰ区主要位于桂中西北部的南丹、环江地区;Ⅱ区主要位于桂中东部柳城、鹿寨地区;Ⅲ区为Ⅰ、Ⅱ区的混源区.母岩主要来源于北部雪峰古陆与东部云开古陆,靠近古陆发育三角洲相沉积,前缘受古地貌、潮汐及波浪影响,形成砂坝或滩.该结果为桂中地区油气勘探评价提供指导.%Guizhong depression, large scale late Paleozoic marine residual basin that formed basically in the stable craton of late Paleozoic to Mesozoic, indicates excellent oil and gas accumulation and exploration potential.Several exploration drilling operations reveal that the generation of the sand reservoir has well matched with the source rock and was covered by finely tight layers in Simen formation in the lower Carboniferous in host area.There are several major discoveries in this type of clastic reservoir in the lower Carboniferous in China, such as Tarim and Ordos basin.In the background of unclear exploration area, the study on this new type of reservoir with great potential is significant strategic.Based on research of the regional geology and analysis of geological and geophysics materials, it worked out that there were 3sources zones, zoneⅠ was mainly located in Nandan and Huanjiang areas in the northwest of Guizhong, zoneⅡ was mainly located in Liucheng and Luzhai areas in the eastern part of Guizhong, and zoneⅢ was the mixed source area.In addition, the mother rock of sandrock came from the Xuefeng landmass in north and the Yunkai landmass in east.There were delta facies near landmass and sand dam distributed in the leading edge area that influenced by ancient landforms, tides and waves.The research results provide guidance for oil and gas exploration evaluation in host area.
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