摘要
渤南油田发育大型低渗透油藏,由于其储层物性差、部署井网时未考虑现今地应力影响,导致压裂改造后发生严重水淹水窜。随着开发的不断深入,须对研究区现今地应力的分布进行系统研究。以渤南油田五区沙三段为例,利用差应变法、声发射法和波速各向异性法等岩心室内实验方法以及测井资料计算,确定渤南油田五区沙三段现今地应力的大小和方向;通过测井资料计算,建立岩石的动、静态力学参数转化关系,求取准确的岩石力学参数并建立地质模型,进而利用有限元数值模拟方法分析现今地应力的分布特征及影响因素。研究结果表明,渤南油田五区现今地应力方向具有明显的分区特征,东部水平最大主应力方向平均为北东61.4°,西部平均为南东58°;水平最大主应力表现为中部低、四周高、环带状分布的特征;水平最小主应力整体具有北高南低的特征,且在研究区中心的局部区域应力值较大。造成现今地应力方向异常主要是研究区东西两侧呈"V"字形分布的断裂系统在近东西向挤压应力作用下派生出对称侧向剪切应力所导致,而剖面应力展布则主要受埋深和岩石力学参数的影响。
The Bonan oilfield,developing large low permeability reservoirs,suffers serious water flood after fracturing because of its poor reservoir property and not considering the influence of current stress during exploitation. It is necessary toresearch the distribution of current stress systematically in the further development. Taking the Es3 of the 5th block ofBonan oilfield as an example,the current stress for the Es3 of the 5th block of Bonan oilfield and its direction were identified by means of laboratory core test method,such as differential strain method,acoustic emission method and velocity anisotropy method;and the relationship between dynamic and static rock mechanical parameters was established by loggingdata interpretation. The relationship between rock dynamic and static mechanical transformation parameters was extractedthrough logging data interpretation to pick up accurately rock mechanical parameters and establish the geologic model,andthen the stress distribution characteristics and influence factors were analyzed combining with the finite element numericalsimulation. The result shows that the current terrestrial stress exists regionally in the 5th block of Bonan oilfield. The maximum horizontal principal stress direction is N61.4°E in the east and S58°E in the west. The maximum horizontal principalstress is low at the center,high in the boundaries with a ring-shaped distribution pattern. The minimum horizontal principal stress decreases from north to south. The regional stress is higher in the study center. The abnormal direction of in-situstress is mainly resulted from symmetric lateral shear forces which are formed when the V-shaped fracture system issqueezed by nearly east-west stress. The section stress is mainly influenced by depth and mechanical parameters.
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2016年第3期26-32,共7页
Petroleum Geology and Recovery Efficiency
基金
国家科技重大专项"精细油藏描述技术及剩余油赋存方式研究"(2011ZX05011)
关键词
沙三段
现今地应力
有限元数值模拟
岩石力学参数
渤南油田五区
Es3
current stress
finite element numerical simulation
rock mechanical parameters
the 5th block of Bonanoilfield
