The fluvial-deltaic reservoirs of the Oligocene Huagang Formation in the Xihu sag of the East China Sea shelf basin reflect rapid lateral change in sedimentary facies and poor morphology of conventional slice attribut...The fluvial-deltaic reservoirs of the Oligocene Huagang Formation in the Xihu sag of the East China Sea shelf basin reflect rapid lateral change in sedimentary facies and poor morphology of conventional slice attributes,which bring difficulties to the reservoir prediction for subsequent exploration and development of lithologic reservoirs.The traditional seismic sedimentology technology is optimized by applying the characteristic technologies such as frequency-boosting interpretation,inversion-conventional–90°phase shift joint construction of seismic lithologic bodies,nonlinear slices,paleogeomorphology restoration,and multi-attribute fusion,to obtain typical slice attributes,which are conducive to geological form description and sedimentary interpretation.The Huagang Formation developed three types of sedimentary bodies:braided river,meandering river and shallow water delta,and the vertical sedimentary evolution was controlled by the mid-term base-level cycle and paleogeomorphology.In the early–middle stage of the mid-term base-level ascending cycle,braided channel deposits were dominant,and vertical superimposed sand bodies were developed.In the late stage of the ascending half-cycle and the early stage of the descending half-cycle,meandering river deposits were dominant,and isolated sand bodies were developed.In the middle–late stage of the descending half-cycle,shallow-water delta deposits were dominant,and migratory medium–thick sand bodies were developed.Restricted paleogeomorphology controlled the sand body distribution,while non-restricted paleogeomorphology had little effect on the sand body distribution.Based on reservoir characterization,the fault sealing type and reservoir updip pinch-out type structural lithological traps are proposed as the main directions for future exploration and development in the Xihu sag.展开更多
HY气田位于西湖凹陷中央反转构造带南部,主要目的层花港组上段为浅水三角洲沉积,储层为中低孔低渗储层,地震响应特征表现为Ⅱ类AVO(Amplitude Variation with Offset)。受压实作用影响,储层孔隙度由上至下逐渐降低,AVO类型由Ⅱb类向Ⅱa...HY气田位于西湖凹陷中央反转构造带南部,主要目的层花港组上段为浅水三角洲沉积,储层为中低孔低渗储层,地震响应特征表现为Ⅱ类AVO(Amplitude Variation with Offset)。受压实作用影响,储层孔隙度由上至下逐渐降低,AVO类型由Ⅱb类向Ⅱa类转变。从岩石物理分析、正演模拟、相位转换及AVO投影角度旋转等方面,制定了针对低渗储层不同AVO特征的精细描述方法。研究认为,区内中孔低渗储层表现为Ⅱb类AVO响应特征,叠后地震砂顶标定于波谷,储层描述应采用叠后-90°相移波形解释、叠后包络属性流体检测等方法;低孔低渗储层表现为Ⅱa类AVO响应特征,储层描述应采用叠后0°相移波形解释、叠前扩展弹性阻抗流体检测等方法。基于上述"一层一策"储层精细描述方法,成功指导研究区多口钻井实施,储层预测及流体检测成功率100%,大幅改善气田开发现状。展开更多
基金Supported by the China National Science and Technology Major Project(2016ZX05027-004)CNOOC(China)Science and Technology Projects(CNOOC-KJ 135,ZDXM 39 SH03).
文摘The fluvial-deltaic reservoirs of the Oligocene Huagang Formation in the Xihu sag of the East China Sea shelf basin reflect rapid lateral change in sedimentary facies and poor morphology of conventional slice attributes,which bring difficulties to the reservoir prediction for subsequent exploration and development of lithologic reservoirs.The traditional seismic sedimentology technology is optimized by applying the characteristic technologies such as frequency-boosting interpretation,inversion-conventional–90°phase shift joint construction of seismic lithologic bodies,nonlinear slices,paleogeomorphology restoration,and multi-attribute fusion,to obtain typical slice attributes,which are conducive to geological form description and sedimentary interpretation.The Huagang Formation developed three types of sedimentary bodies:braided river,meandering river and shallow water delta,and the vertical sedimentary evolution was controlled by the mid-term base-level cycle and paleogeomorphology.In the early–middle stage of the mid-term base-level ascending cycle,braided channel deposits were dominant,and vertical superimposed sand bodies were developed.In the late stage of the ascending half-cycle and the early stage of the descending half-cycle,meandering river deposits were dominant,and isolated sand bodies were developed.In the middle–late stage of the descending half-cycle,shallow-water delta deposits were dominant,and migratory medium–thick sand bodies were developed.Restricted paleogeomorphology controlled the sand body distribution,while non-restricted paleogeomorphology had little effect on the sand body distribution.Based on reservoir characterization,the fault sealing type and reservoir updip pinch-out type structural lithological traps are proposed as the main directions for future exploration and development in the Xihu sag.
文摘HY气田位于西湖凹陷中央反转构造带南部,主要目的层花港组上段为浅水三角洲沉积,储层为中低孔低渗储层,地震响应特征表现为Ⅱ类AVO(Amplitude Variation with Offset)。受压实作用影响,储层孔隙度由上至下逐渐降低,AVO类型由Ⅱb类向Ⅱa类转变。从岩石物理分析、正演模拟、相位转换及AVO投影角度旋转等方面,制定了针对低渗储层不同AVO特征的精细描述方法。研究认为,区内中孔低渗储层表现为Ⅱb类AVO响应特征,叠后地震砂顶标定于波谷,储层描述应采用叠后-90°相移波形解释、叠后包络属性流体检测等方法;低孔低渗储层表现为Ⅱa类AVO响应特征,储层描述应采用叠后0°相移波形解释、叠前扩展弹性阻抗流体检测等方法。基于上述"一层一策"储层精细描述方法,成功指导研究区多口钻井实施,储层预测及流体检测成功率100%,大幅改善气田开发现状。
