酒泉盆地晚白垩世—古新世构造特征

A study on characteristics of the Late Cretaceous-Paleocene structures in Jiuquan Basin

酒泉盆地普遍发育了始新统与下白垩统之间的不整合。通过对地震剖面和下白垩统中沟组残余厚度的分析,提出了酒泉盆地晚白垩世—古新世发生了强烈的构造变形,构造线总体方向为北西向。晚白垩世—古新世的变形导致了早白垩世连通的酒泉盆地和民乐盆地、酒泉盆地的花海凹陷和石大凹陷开始分割。该期变形还对盆地的油气聚集和后期的沉积起到了控制作用。

The unconformity between the Eocene and the Lower Cretaceous is common in Jiuquan basin. Based on analyses of the seismic profiles and remnant thickness of the Lower Cretaceous Zhonggou Formation, it is suggested that a strong structural deformation had happened during the Late Cretaceous-Paleocene, resulting in generally NW-trending structural lines in the basin. The deformation resulted in the separation of Jiuquan Basin from Minle Basin that were previous connected in the Early Cretaceous and Huahai depression from Shida depression in Jiuquan basin. It also controlled the hydrocarbon accumulation and the later sedimentation in the basin.