渤海湾盆地东濮凹陷的形成及断裂构造研究

讨论了中、新生代以来．中国东部构造应力场的变化及其对渤海湾地区的影响、作用；提出渤海湾盆地是在中国东部陆壳伸展、拉张作用的构造背景上，叠加右行走滑拉分作用形成的“拉分──伸展型”复合盆地．东濮凹陷作为渤海湾盆地系统的一部分，具有与渤海湾盆地相同的基底构造和相似的构造演化历史．本文通过对东濮凹陷基底断裂构造的特征及沿兰聊断裂两侧众多探井岩芯破裂构造的观察、分析和研究，证实了兰聊断裂在东濮凹陷形成过程中的右行平移作用．

STUDY ON THE FORMATION AND FAULT STRUCTURES OF THE DONGPU DEPRESSION OF BOHAI GULF, EASTERN CHINA

The Bobal Gulf basin located in eastern China is a great Cenozoic basin,beating huge amount of oil and natural gas resources, and Dongpu depression setting at the south end of the Bobal Gulf basin is a critical part of the Gulf basin. The plate tectonic setting and the Changing of structural stress field in eastern China, and their influences and effects on the Bobal Gruff region during the Mesozoic and Cenozoic were discussed in this Paper. The present authors suggested that the Bobal Gulf basin was a pull-apart extension composite basin resulting from the superimposition of the continental crustal extension of eastern China and the pull-apart process by the dextral strike slip displacement along the Tan-Lu fault and the Lan-Liao fault. The Dongpu depression, asia part of the Bobal Gulf basin, has the same basement structures and a similar tectonic evolution history. The evolution of the Dongpu depression canbe divaaed into five.periods i.e. 1. genetic stag4 two grabens and a host were formedi 2. development stage, the oil and natural gas were generated; 3. decrease stag6, the extension decreased and some erosion occurred on the margins of the depression; 4. old stage; 5. ending stage, cooling subsidence happened. In the light of the observation, analysis and study on the characteristics of the features of the basement fault of the Dongpu depression and the fractural structures in the cores from the boreholes along the both sides of the Lan-Liao fault, the dextral strike slip along the Lan-Liao fsult during the formahon process of the Dongpu depression was identified.