普光地区中三叠统雷口坡组顶部储层分布预测

Reservoir distribution prediction on the top of Middle Triassic Leikoupo Formation in Puguang Area

普光地区雷口坡组顶部储层薄,与围岩物性的差异小,地震响应微弱,难以识别,对储层预测造成了极大的困扰。针对这一难点,利用反褶积拓频和90°相位转换技术对地震资料进行了处理,并利用处理后的资料进行储层标定,明确储层的地震响应特征;在此基础上,利用属性分析、波形聚类、相干分析、波阻抗反演等方法进行了储层预测。预测结果表明储层分布主要受古地貌和断裂的控制,工区西南部是储层发育的有利区域。在普光地区应用表明:通过反褶积拓频和90°相位转换对地震资料的处理,突出了雷口坡组顶部薄储层(5~20m)的地震响应特征;并形成了一套以精细标定为基础、适合雷口坡组顶部储层的预测思路,预测结果可靠性较高。

Reservoirs buried in the uppermost part of the Middle Triassic Leikoupo Formation in Puguang are characterized by thinness,little difference of surrounding rock physics,and weak seismic response.So they are very difficult to be identified.To solve this problem,we first use deconvolutionbased frequency expansion and 90°-phase shifting to process seismic data.Then we calibrate reservoirs on the processed seismic data and determine clearly reservoir seismic response.On this basis,we conduct reservoir prediction with different ways such as attribute analysis,waveform clustering,coherence analysis,and impedance inversion.According to our prediction,the reservoir distribution is mainly controlled by ancient landform and fractures,and the southwest part of the study area is favorable for reservoir development.Our applications in Puguang Area shows that deconvolution-based frequency expansion and 90°-phase shifting highlight thin reservoirs(5~20 m)in the top Leikoupo Formation,and ensure high reliability of thin reservoir prediction.