陡坡带砂砾岩体油藏是断陷盆地油气勘探的主要类型之一.钻井证实,渤海湾盆地济阳坳陷近EW向断层下降盘近源粗碎屑沉积物发育,而N(N)E向断层下降盘近源沉积欠发育或不发育.针对这一特殊地质现象,在凸起区剥蚀量恢复的基础上,探讨了凸起与凹(洼)陷的耦合关系,划分出凸隆凹降型和凹降凸隆型2种关系类型;以现代沉积考察为依据,提出物源区面积、剥蚀厚度以及物源沟谷发育程度等是近源沉积物发育与否的主控因素;研究了EW向断层和N(N)E向断层下降盘的沉积特点,指出在古近纪SN向拉张应力状态下,EW向断层属于同沉积断层,NNE向断层以右旋走滑作用为主,运动学性质和活动时间的不同是沉积差异性的主因.%Glutenite oil deposits in steep slope zone are major hydrocarbon exploration targets in rift basins. Drilling proves that near?source coarse debris sediments were well developed on the downthrown side of EW oriented faults. On the contrary, near?source sediments seldom or even did not develop on the downthrown side of N(N)E oriented faults. The article discussed the coupling relationship between bulge and depression, and came up with two kinds of coupling relationship which are the mountain?upheaval basin?sedimentary type and basin?sedimentary mountain?upheaval type, focusing on this special phenomenon and based on the recovery of the denudation quantity in the bulge area. Prove?nance area, erosion thickness and passageway development degree determined whether near?source sediments deposited or not based on the studies of the Dabie orogenic belt. The deposition characteristics of the downthrown side of the EW and N(N)E oriented faults were analyzed, indicating that the EW faults are syndepositional ones and the N(N)E faults are right?lateral strike-slip ones influenced by the SN extensive stress during Paleogene. The difference between kinematic properties and activity time is the main cause of sedimentation difference.
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