塔中顺西三维区碳酸盐岩储层预测方法研究及应用

Study and Application of the Prediction Method of Carbonate Reservoir in Shunxi 3DArea of Tazhong

顺西地区奥陶系碳酸盐岩储层埋深大、地质情况复杂、岩溶发育强度总体较弱,储层厚度不大,储层与非储层段地球物理特征差异小,沙漠区地震资料品质差,给该区储层地震识别模式的认识、响应特征的总结以及有效储层的预测评价带来了诸多困难。为了解决该区目标储层反射特征不清,识别预测精度不高,"串珠"之外储层如何预测等问题,进而有效预测不同层系缝洞型储层发育区带、落实优选圈闭及勘探目标。首先在三维目标处理地震资料基础上,结合区内钻井、测井及地质综合解释等资料,分层系建立符合地下地质特征的缝洞型储层模型,并开展正演模拟分析工作;然后在此基础上总结各层系储层地震识别模式,明确储层地震响应特征;最后建立了一套适合顺西地区的碳酸盐岩储层预测方法技术系列。通过方法技术的实施,在顺西三维区发现、落实了一批圈闭,并在优选部署的多口井获得了油气发现,研究应用取得了较好的效果。

The Ordovician carbonate reservoir in Shunxi area usually has a larger burying depth,complicated geological conditions,slighter karstification and small reservoir thickness.More importantly,the difference of geophysical features between reservoir and nonreservoir is little,and the quality of seismic data in desert area is poor.All these factors bring some problems in constructing seismic reservoir identifying patterns,summarizing reservoir response characteristics and predicting and evaluating the reservoir effectively in this area.In order to solve the problems that the reflection characteristics of target reser-voir are unclear;prediction accuracy is not high,and how other reservoir types but ＂ beaded reservoir＂ are forecast in Shunxi area,the paper carries out a lot of research work to predict the favorable and fractured reservoir zone in different strata,to choose preferential traps and to realize exploration targets.On the basis of processing seismic data by using 3 Dtarget,the geological models are established for different types of fracture-cavity reservoirs,with the combination of the actual drilling,logging and geological interpretation data.After forward analysis in this district,the result summarizes seismic and attribute response characteristics of carbonate reservoir,and investigates the method to predict effective reservoir.Through the implementation of methods and techniques,a number of traps are found in the three-dimensional area of Shunxi,and multi-wells detection gets a breakthrough in finding oil and gas.Compared with exploration practice,the predicted results are basically consistent with the actual data.It has some reference value in carbonate reservoir prediction in Shunxi area or other similar background reservoir.