冀中坳陷束鹿凹陷潜山分类与成藏模式

冀中坳陷束鹿凹陷发育于太古宙变质岩结晶基底上,其经历了中晚元古代裂陷槽阶段、古生代克拉通盆地阶段、中生代构造转换调整阶段和新生代断陷型盆地等4个阶段,为一典型地台-断陷-坳陷多层结构的复合盆地。盆地历经多次构造运动改造,潜山较发育,类型多样。在总结前人对潜山研究的基础上,结合束鹿凹陷三维连片地震资料,对该地区潜山类型进行系统划分,并对典型潜山的构造特征及生储盖匹配关系进行了描述。研究区潜山根据成因可划分为剥蚀型潜山和拉张型潜山两大类,根据形态可划分为剥蚀残丘型潜山、不整合潜山、断阶型潜山、断槽冲蚀沟型潜山、断垒型潜山和断块型潜山等类型。束鹿凹陷潜山的发育具有分带性,按潜山的构造位置,分为凸起潜山带、缓坡潜山带、洼槽潜山带和陡坡潜山带,不同构造带发育不同类型的潜山。研究结果表明束鹿凹陷中新元古界、古生界潜山数量众多,规模较大,是束鹿凹陷实现油气突破的一种重要油气藏类型。

Tectonic Characteristics and Hydrocarbon Accumulation Models of the Buried-hill in Shulu Sag,Jizhong Depression

The Shulu Sag was developed on the Archaean metamorphic crystalline basement, and had undergone four tectonic stages: Meso-/Neo-Proterozoic rifting, Paleozoic cratonic basin, Mesozoic tectonic transformation-modification and Cenozoic fault-depression basin. It is a typical multi-layered basin of platform-fault-depression. Due to the multiple tectonic movements, various buried hills are well developed. Based on previous buried hill studies and combining with 3D multi-block-jointed seismic data from the Shulu sag, the local buried hill types are systematically classified, and their tectonic characteristics and source-reservoir-cap correlation are described. We divided the buried hills into denudation and stretch types according to their origin, and into denudation stump, unconformity, fault-step, fault-channel erosion ditch, fault-barrier and fault-block types based on their morphology. Buried hill development in the Shulu sag exhibits zonation patterns, and according to the tectonic location it can be divided into raised, gentle-slope, trough, and steep-slope buried hill belts. Different types of buried hills were developed in the different tectonic zones. We show that there are a large number of large-scale buried hills in the Mesoproterozoic and Paleozoic Shulu sag, which is an important type of oil-gas reservoir for exploration breakthrough in the sag.