基于地应力的库车前陆盆地储层有效性测井评价

库车前陆盆地高陡构造的白垩系致密砂岩储层处于异常高压和强地应力状态,常规测井解释技术评价该类储层有效性的结论常与试油结果相矛盾,影响了该类油气田的高效开发。针对该类低孔隙度裂缝性高压储层,从岩石力学角度出发,准确计算高陡构造地层的地应力,研究其与储层有效性的对应关系,提取有效应力比和走向应力差等参数,建立储层有效性评价标准并识别优质储层,形成了一套基于地应力的高陡构造储层有效性的测井评价方法,为研究区深层裂缝性砂岩储层有效性的测井评价提供了全新的途径,也为试油和压裂酸化等选层提供了可靠的岩石力学依据。将该方法用于新井储层有效性评价中,效果良好。

Log Evaluation of Reservoir Validity from Formation Stress in Kuche Foreland Basin

Because the cretaceous tight sandstone reservoir in the front of high steep tectonic of Kuche forelandbasin is abnormally high pressure and strong stress,it is difficult for the conventional well logging interpretation technique to evaluate the effectiveness of the reservoir accurately.The evaluation result is often inconsistent with the oil/gas test,which affects the effectiveness of the exploitationin.Hence,it is necessary to understand the correlation of the crustal stress value and direction with the reservoir validity and how to evaluate reservoir validity.From the perspective of rock mechanics,firstly calculated the crustal stress of high deep tectonic formation,and then studied the corresponding relation of situ stress and reservoir validity,and extracted such parameters as effective crustal stress ratio and direction stress difference,and established evaluation criteria of reservoir validity and distinguished high-quality reservoir,and finally formed a set of key methods and techniques toevaluate the reservoir validity of high steep tectonic.T his set of method and techniqueprovides a full new approachtoevaluate the deep fractured sandstone reservoir validity from well logging information.Anditalso provides reliable rock mechanics basis for selecting layer in oil testing,acidification and fracture.Good results has been achieved to apply this method to reservoir validity evaluation of new wells.It is worthy of popularization and application.