【摘要】 由于大杨树盆地表层广泛分布的火山岩的强反射屏蔽作用造成地震中、深层反射能量弱,致使盆地基底(T5)及主要目的层九峰山组、龙江组沉积岩分布范围不清,严重制约了勘探进程。通过在GM-SYS重磁拟合软件中加载地震剖面,在地震解释的基础上建立重磁模型,利用地震浅层可靠解释成果做约束条件,减少了重力反演深层构造界面的多解性。在消除高位玄武岩的重力干扰效应后,反演了基底深度,揭示了大杨树盆地南部坳陷区基底形态为两断阶(西部断阶、东部断阶)夹两凹一凸(太平川断陷、玉林屯断陷及格泥乡凸起)的构造格局。经综合分析认为,玉林屯断陷为有利勘探目标区,预测了主要目的层九峰山组、龙江组沉积岩分布范围,为该区的进一步油气勘探奠定了基础。更多还原

【Abstract】 The weak reflected energy in middle and deep strata, which is caused by the shielding effect of strong reflection of the volcanic rocks widely distributed on the surface of Dayangshu Basin, leads to the unknown distribution of sedimentary rocks in the basement (T5) and such main target formations as Jiufengshan Formation and Longjiang Formation, severely limiting the exploration progress. Through embedding seismic profile in simulated GM-SYS gravity and magnet software, a gravity and magnetic model is established based on seismic interpretation. The multiplicity of deep structure interface of gravity inversion is decreased based on taking the available explanation achievements of shallow strata as restrictions. After eliminating the gravity interference effect of the high-locality basalts, the inversion of the base depth is carried out. The basement of the south depression in Dayangshu Basin features in two fault terraces (western and eastern fault terraces), two sags (Taipingchuan and Yulintun faulted-depressions), and one uplift (Genixiang uplift). On the basis of combinational analysis, Yulintun depression is thought to be a favorable target of exploration, which lays a solid foundation for predicting the distribution of Jiufengshan and Longjiang Formations.更多还原