【摘要】 综合利用钻井、分析化验、岩心等资料,研究北部湾盆地福山凹陷西部地区流二段(流沙港组二段)湖底扇的沉积特征及成因机制,通过钻井标定,结合地震属性分析,精细刻画湖底扇体的空间分布形态。结果表明,流二段湖底扇形成于福山凹陷的缓坡带一侧,其受控于同生断裂所形成的断裂坡折;流二段湖底扇主要由南部辫状河三角洲前缘滑塌体经过多级断裂控制后进入湖底形成,具有近物源区、多期叠置发育的特点;流二段湖底扇形成于低位体系域形成晚期,主要包括浊积型、滑塌型两种成因类型,扇体形成的触发机制主要为凹陷内强烈的火山活动;流二段湖底扇上部及下部发育巨厚的暗色泥岩,是凹陷内最主要的烃源岩,对油气勘探具有重要意义。更多还原

【Abstract】 By comprehensive use of drilling data, analysis assay, core data, etc., the sedimentary characteristics of sublacustrine fan in the second member of Liushagang formation in the western area of Fushan Sag, Beibuwan Basin are studied. Through drilling calibration and with the seismic attributes analysis, the spatial distribution of sublacustrine fan is described in detail. The research shows that the sublacustrine fan formed along the side of slope belt, and was controlled by the faulted slope break background formed by synsedimentary faults. The slumps of the northern braided delta front were transported via multi-fault-terrace to the lake bottom and the sublacustrine fan was formed. The fan was with the characteristics proximal to source area, and of multi- superimposed development. They were formed during the late of the lowstand period, including the turbidite and slump types. The trigger mechanism of the fan is the intensive volcanic activities within the sag. There are thick dark mudstones in the upper and the lower parts of the fan, which constitute the main source rocks in the sag and are significant for petroleum exploration.更多还原