摩洛哥近海杜卡拉盆地构造特征及油气勘探前景

Structural characteristics and hydrocarbon exploration prospects of the Doukala Basin, offshore Morocco

  • 摘要: 摩洛哥近海杜卡拉盆地油气资源丰富,目前对该区域的构造演化特征及油气地质条件缺乏系统认识。本文基于前人研究成果,结合地震资料精细解剖,总结了杜卡拉盆地构造特征,分析了构造演化过程及构造变形机制,探讨了油气成藏特征。结果表明,杜卡拉盆地伸展变形表现为东强西弱、南强北弱的特征,盐构造变形表现为中部强两侧弱、南强北弱的特征,挤压变形表现为东部隆升、西部稳定的特点。盆地具有“横向分带、纵向分层” 的基本特征,区域上自西向东可划分为贫盐稳定带、富盐底辟带和贫盐挤压带,剖面上则自下而上构成了“断陷-隆坳相间-坳陷”的三层结构。盆地演化经历了裂谷阶段、稳定漂移阶段及侧向挤压阶段,且构造变形迁移及盐流动差异性造成了盆地构造变形在空间上的差异。此外,杜卡拉盆地发育志留系-三叠系和侏罗系-白垩系两套油气成藏组合,其中盐上下白垩统油气藏是研究区重点勘探目标。

     

    Abstract: The Doukala Basin off the coast of Morocco is rich in hydrocarbon. However, there is a lack of systematic understanding of the structural evolution characteristics and geological conditions of hydrocarbon. Based on previous research results and combined with detailed seismic data interpretation, we summarized the structural characteristics, analyzed the structural evolution process and structural deformation mechanism of the Doukala Basin, and discussed the characteristics of hydrocarbon accumulation. Results show that the extensional deformation of the Doukala Basin is characterized by stronger deformation in the east and weaker in the west, and stronger in the south and weaker in the north. The salt structural deformation is characterized by stronger in the middle and weaker on both sides, and stronger in the south and weaker in the north. The compression deformation is characterized by uplift in the east and stability in the west. The Basin has the basic characteristics of “horizontal zoning and vertical stratification”. Regionally, from west to east, it can be divided into a salt-poor stable zone, a salt-rich diapir zone, and a salt-poor compression zone. On the cross-section, it formed a three-layered structure of “fault depression — uplift-depression alternation — depression”. The basin evolution went through a rift stage, a stable drift stage, and a lateral compression stage, and the migration of structural deformation and salt flow differences have caused spatial differences in basin structural deformation. In addition, the Doukala Basin has two hydrocarbon accumulation assemblages of the Silurian-Permian and the Jurassic-Cretaceous, of which the Lower Cretaceous oil and gas reservoirs above the salt layer are the key exploration targets in the study area.

     

/

返回文章
返回