裂陷盆地构造演化及盆地伸展模式—以东濮凹陷为例

Tectonic evolution and extensional pattern of rifted basin:a case study of Dongpu depression

苏惠 曲丽萍 张金川 王萍霞 何锋 王敏 王琦 胡玉杰

Su Hui Qu Liping Zhang Jinchuan Wang Pingxia He Feng Wang Min Wang Qi Hu Yujie

东濮凹陷是我国东部典型的裂陷盆地。盆地的构造演化经历了早古生代至三叠纪的克拉通盆地旋回和新生代的裂陷盆地旋回。新生代裂陷盆地旋回又划分为早期裂陷、强烈裂陷、晚期裂陷和晚第三纪整体坳陷4个阶段。东濮凹陷基底伸展量的变化总趋势是由北向南加大,地壳上部的伸展构造变形为简单剪切伸展模式,而地壳下部具有纯剪切机制。滑脱面变异带可能是造成东濮凹陷内桑村集-桥口-白庙横向构造变换带、南北构造活动差异性以及油气富集程度差异性的重要原因。

Dongpu depression is a typical rifted basin in eastern China. The tectonic evolution of the basin includes an Early Paleozoic-Triassic cratonic basin cycle and a Cenozoic rift basin cycle. The latter can be subdivided into 4 stages, including initial rifting, intense rifting, late rifting and Late Tertiary integral downwar-ping. The basement extension in Dongpu depression increases, as a whole, from north to south. The extensional tectonic deformation is of simple shear extensional pattern in the upper earth crust, and of pure shear extensional pattern in the lower earth crust. The mutation zone of detachment surface might be the main factor causing the lateral tectonic transformation belt from Sangcunji to Qiaokou to Baimiao, and the difference of tectonic activity and the enrichment of oil and gas in the northern and southern parts of Dongpu depression.

10.11743/ogg20060112