流体包裹体技术在断裂构造分析中的应用

Application of fluid inclusion in analysis of faulted structure

断裂是油气运移的主要通道之一,断裂带岩石中的包裹体可以反映流体当时的物化性质及断裂性质。通过对断裂带中流体包裹体成分及镜下特征的研究可以判断断裂的力学性质;利用包裹体均一温度可以判断断裂带内流体活动时期,达到间接判断断层的活动期次。以平南油田平南断裂中流体包裹体的分析测试为例,通过研究,表明平南断裂是一条经历了正、反转运动的复杂断裂;均一温度测试表明,平南断裂带中有2期油气运移事件发生,对应的温度分别为60-85℃和90-120℃,并对应着断裂2个期次的活动。

Faults were one of the important paths of oil and gas migration.Fluid inclusion in the rocks of faulted zone can reflect the physical and chemical properties of the fluid and fracture property.The mechanic property of a fault can be decided by the composition and features of fluid inclusions under microscope.The active period of a fluid within a faulted zone can be decided by the homogenization temperature of fluid inclusions,so as to indirectly determine the active stages of a fault.The study on the fluid inclusions in the Pingnan fault of the Pingnan oilfield indicates that this fault had experienced normal and reverse movements.A test of homogenization temperature shows that there were two stages of oil and gas migration in the Pingnan faulted zone,at respective temperatures of 60-85℃ and 90-120℃,corresponding to two stages of fault movements.