东北地区白垩纪断陷盆地群形成模式及其油气地质意义

Formation Models of Northeast Group of Cretaceous Rift Basin and Their Petroleum Geological Significance

东北地区白垩系断陷盆地群是在古生代褶皱造山带的基础上发展起来的早白垩世宽范围火山断陷盆地群,经历了一个完整的拉张断陷到挤压回返的构造旋回,伸展作用强烈,坳陷广泛发育,具有构造样式复杂、垒堑相间、断超结构的特点。郯庐断裂带北段在早白垩世发生的左旋走滑运动控制了断裂带两侧盆地的发育。中生代断陷盆地群是在较新的地壳上发展起来的,中酸性火山活动强烈,在松辽盆地和海拉尔盆地存在两个岩石圈减薄区。断陷盆地群具有相似的构造特点,火山断陷作用强烈。在前人研究的基础上,证实了松辽盆地存在裂前隆起。本文从裂谷成盆模式模式入手,认为断陷盆地群东部是窄裂谷成盆模式,西部及中部是宽裂谷成盆模式,认为东北断陷盆地群是在幔隆过程中形成。

The Cretaceous fault basin group in northeast China is the group of early cretaceous wide range volcanic fault basin which developed on the basic of paleozoic fold orogenic belt. It goes through a complete tectonic cycle from extension to extrusion, with strong extensional regime and widely developed depression. It has characteristics of complex structural style, uplifted and depression units and fracture-overlap structure. The left-lateral strike slip motion took place in early cretaceous in northern section of the Tan-Lu in the Early Cretaceous that controls the bilateral basin development. The Mesozoic fault basin group was developed on the compared newer crust, and it has a strong intermediate-acid volcanic activity. There are two lithosphere thinner areas in the Songliao and Hailer basin. The fault basin group has similar characteristics and strong volcanic fault effect. In previous studies, based on the sum of six evidences, we confirmed the existence of uplift before cracking in Songliao basin. This study started from the model of rift into basin. And we think that the east fault basin group is the narrow rift into basin model, the western and central is the wide rift into basin mode, and the fault basin group in northeast China was formed during the mantle uplift.