【摘要】 四川盆地拉张断裂在地震资料中的识别研究,印证了晚元古-早古生代盆地处于张性构造作用环境。结合川中地区新老探井地层对比,提出存在早寒武世拉张槽的观点。使用四川盆地钻至寒武系和震旦系的探井约束解释覆盖全盆地的二维、三维地震资料后,以下寒武统麦地坪组、筇竹寺组和沧浪铺组3套地层总厚度展布特征,揭示了拉张槽在平面上为近南北走向;确定了四川盆地早寒武世拉张槽两侧边界(断裂)东陡西缓的特征,中段呈箕状拗陷构造形态。以其展布中线区域,命名为绵阳-乐至-隆昌-长宁拉张槽。更多还原

【Abstract】 The study and identification of the extensional structures in the pre-Sinian to Cambrian strata confirm the extensional tectonic setting during the late Proterozoic-early Palaeozoic in Sichuan Basin.The paper proposes the view of the existence of the Early Cambrian Mianyang-LezhiLongchang-Changning intracratonic sag by interpreting the drilling well information and seismic profiles.In the section,the Early Cambrian intracratonic sag possesses the general characteristics of half-graben.Its boundaries are steep on the east side and relatively gentle on the west side.The east steep boundary is more obvious in the middle segment of the sag,and weak in the north and south segments.On the plane,the distribution of the thickness of Lower Cambrian Canglangpu,Qiongzhusi and Maidiping Formations shows that the sag is wide in the north and south segments,and narrow in the middle segment.The determination of the early Cambrian intracratonic sag is of great importance to the petroleum exploration in Sichuan Basin.更多还原