塔河油田三叠系阿四段超深层河道砂识别与描述技术

The Identification and Description of the Super Deep Channel Reservoir of T_2a^4 in Tahe Oilfield

塔河油田三叠系阿四段水下分流河道砂岩性圈闭是碎屑岩领域近几年增储上产的重要目标,该类圈闭埋藏深(>4 200m),砂岩厚度薄(<15m),横向变化快,地震识别难度大。通过近几年实践总结,研究开发了一套针对阿四段河道砂识别与描述技术:利用正演模拟技术确定河道识别标志、属性提取及RGB分频混色技术落实河道边界、拟声波阻抗反演结合振幅属性预测砂体厚度、频率衰减梯度属性辅助进行流体检测。通过多技术方法的综合应用,在塔河油田阿四段共落实河道15条,其中6条河道已开发评价。河道砂岩性油藏的发现不仅扩大了塔河油田碎屑岩领域勘探开发阵地,同时也为寻找岩性圈闭积累了宝贵经验。

Channel sand reservoir of T2a4 played an important role in production in Tahe oilfield.Such traps are characterized by high buried depth（more than 4 200 meters）,small sand thickness（less than 15meters）and large lateral variation,which is difficult to be identified and evaluated.Through the practice in recent years,a series of techniques for identification and evaluation of deep channel sandstone reservoirs in Tahe oilfield are developed.Using forward simulation technique to determine the channel identification mark,attribute extraction and RGB plotting technique implement the river boundary.The prediction of sand body thickness with the combination of acoustic impedance inversion and amplitude attribute and frequency attenuation gradient attribute is used for fluid detection.Through the comprehensive application of multi technology method,15 rivers of T2a4 have been carried out in Tahe oil field,and 6rivers have been evaluated.The discovery of the channel sandstone reservoir not only expands the exploration and development of the clasticrocks in Tahe oilfield,but also accumulates valuable experience for the exploration of lithologic traps.