【摘要】 胶莱盆地为中生代残留盆地,受郯庐断裂带、牟—即断裂带活动的影响,盆地南部、东北部地震活动强烈,发育一系列与地震作用有关的地震事件沉积构造。利用大量的岩心、野外露头资料,在胶莱盆地东北部下白垩统莱阳组砂泥质沉积物中可识别出两大类地震事件沉积构造:软沉积物变形构造(液化变形构造、拉伸变形构造、挤压变形构造)和硬岩层脆性变形构造,共计9小类,并对其成因机制进行了分析。盆地东部的牟—即断裂带是一条重要的控盆边界断裂带,在莱阳组沉积时期以NW-SE向伸展构造活动为主,致使盆地东北部地震活动频发,盆地内早期沉积的莱阳组以普遍发育震积岩为特征,且以软沉积物液化变形为主,反映地震强度为5<Ms<8。地震活动使岩层产生大量的微裂缝,裂缝沟通了原有的孔隙,使渗透率大幅度增加。震积岩的发现可以合理解释研究区水南段泥岩中浊积岩的触发机制为地震作用,地震活动诱发形成的震浊积体易形成岩性圈闭,为油气勘探提供了新的视角和领域。更多还原

【Abstract】 The Jiaolai Basin is a Mesozoic residual basin.The southern and northeastern parts of the basin were intensively affected by Tanlu and Mou-Ji Faults in the Cretaceous,and several types of deformational structures that are interpreted as seismites were formed.Based on core and outcrop observation,two types of sedimentary structures formed by seismic events were observed,including deformation structures of soft-sediments(liquefied deformation structure,stretch deformation structure,stress deformation structure)and hard rock.These sedimentary structures can be subdivided into 9 subclasses,and their genetic mechanisms were analyzed.The Mou-Ji Fault is a main fault which controlled the formation of the Jiaolai Basin,and stretched with NW-SE direction in Laiyang Formation depositional period,which caused frequent earthquake in the northeastern Jiaolai Basin.As a result,seismites were formed and were dominated by liquefied deformation of soft-sediments,which demonstrated the earthquake intensity was 5<Ms<8.A large number of micro-fractures in rocks were formed due to the earthquake,and the pores were connected by micro-fractures,which finally increased the permeability of rocks.The trigger mechanism of turbidite of the Shuinan Member can be explained as earthquake according to the discovery of seismites.Seismo-turbidites can be preserved as diagenetic traps because of dissolution caused by organic acids,which provides a new perspective and field for oil and gas exploration.更多还原