渤中、渤东凹陷结构认识及有利勘探方向

渤中、渤东凹陷沙河街组三、四段为断陷沉积:凹陷东部断陷沉积受NE向断裂(郯庐断裂系)控制.雁行排列的NE向断裂将其分隔成3个主半地堑.凹陷西部断陷沉积受NW或近E-W向断裂控制,亦形成3个主半地堑.断陷期的沙河街组三段是凹陷的主力烃源岩,厚度可达3000m,而东营组下段生油指标达到好烃源岩标准,也是一套值得重视的烃源岩.环渤中凹陷的诸多凸起是寻找上第三系油藏的有利地区,凸起边缘和凹中隆则是寻找上第三系油藏和东营组优质油气藏的有利地区.

GEOLOGICAL CONFIGURATION AND POTENTIAL EXPLORAITON AREAS OF BOZHONG AND BODONG SAGS

Bozhong and Bodong sags were at a rfifting stage during the deposition of 3rd/4th members of Shahejie formation. In the eastern part of Bozhong sag, sedimentation of rifting stage was controlled by NE striking fault system(Tanlu fault system)which was characterized by an echelon pattern, and three major half grabens were formed. In the western part of the sag,sedimentation was controlled by NW or nearly EW striking faults which formed another three major half grabens. The 3rd member of Shahejie formation deposited during rifting stage contains major source rocks with its thickness up to 3000m. Lower Dongying formation is a set of potential source rock with geochemical parameters up to the criteria of good source rocks. Uplifts encircling Bozhong sag are favorable areas for searching upper Tertiary oil accumulations,and the marginal areas of the uplifts and the low relief uplifts within the sag are the prospective areas for searching upper Tertiary oil accumulations and good quality oil and gas in Dongying formation.