摘要
东营凹陷八面河地区发育多期不整合,其中孔店组底界的区域性不整合对研究区深层油气成藏具有重要的控制作用。大量地震资料解释结果表明,八面河地区发育削超、平超和削平3种不整合类型。根据岩性及测井资料分析,将不整合在纵向上划分为不整合之上岩石、不整合之下风化粘土层和半风化岩石3层结构;受风化淋滤作用影响,半风化岩石的储层物性可以得到不同程度的改善。不整合构成了八面河地区油气侧向运移的重要通道,众多油气显示或油气藏均位于不整合上、下40 m范围内。研究区不同的不整合类型与其上、下岩性相配置,可形成12种不整合岩性组合模式,对油气运聚成藏具有不同的控制作用。在八面河地区削超型和平超型不整合分布区,若纵向上为砂—泥对接岩性组合,可在不整合之上的孔店组形成地层超覆油气藏;在削超型和削平型不整合分布区,若纵向上为泥—砂对接岩性组合,可在不整合之下形成潜山油气藏。
Multiphase unconformities were found in the Bamianhe area of Dongying sag. The unconformity in the bottom of the Kongdian formation is very important for petroleum accumulation in this area. Seismic section was comprehensively interpreted to discover three unconformity types including truncation-overlap unconformity, parallel-overlap unconformity and truncation-parallel unconformity. According to the log data analysis, the unconformities were divided into three parts vertically: rocks deposited above the unconformity interfaces, weathered clay layer and semi-weathered rocks below the unconformity interfaces. Under the weathering and leaching action,the permeability of semi-weathered rocks is improved. Based on the combination of different unconformity types and lithologic configurations, 12 lithological combination types were proposed, which play different roles in the oil and gas migration and accumulation. The exploration has proved that numerous oil and gas shows and petroleum accumulations exist within 40 m range both above and below the unconformity interfaces. The stratigraphic overlap reservoirs can form above the unconformity interfaces in the area where the truncation-overlap and the parallel-overlap unconformities develop combined with sand-mud lithologic configuration; the buried hill reservoirs can form below the unconformity interfaces in the area where the truncation-overlap and the truncation-parallel unconformities develop with mud-sand lithologic configuration.
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2014年第6期37-40,113,共4页
Petroleum Geology and Recovery Efficiency
