大情字井地区特征参数反演储层预测

Reservoir prediction using characteristic parameter inversion in Daqingzijing Area

高精度特征参数反演是目前储层横向预测的手段之一,是波阻抗反演效果不理想情况下的岩性反演,适用条件是储层特征曲线同地震记录能建立良好关系,储层特征曲线与地震记录砂体响应关系良好。文中在详细分析松辽盆地大情字井地区青山口组地质、测井、沉积相、岩性特征及地球物理参数的基础上,采用对储层岩性特征刻化明显的自然伽马和自然电位测井曲线,对三维工区内青山口组青一段7小层进行了拟声波反演,并将反演结果与常规声波阻抗反演结果进行比较,发现自然伽马拟声波反演对识别工区内砂泥岩界面具有更高的精度和分辨率。在此基础上,采用伽马特征反演方法开展青一段7小层砂岩储层预测,预测砂体厚度分辨率达到2 m,预测厚度及平面展布范围与实钻结果吻合度较高,为该层的岩性-构造圈闭确定、滚动勘探及开发井网设计提供了可靠的地质依据,进一步证实了储层特征参数反演技术在钻井较多的开发区具有一定的实用性。但应注意,不同地区应用效果也会有所不同,还需要进一步实践验证和改进。

High-precision characteristic parameter inversion is one of the present technologies in lateral prediction of reservoir, It is a type of lithologie inversion used while the wave impedance inversion result is not good. It needs that the characteristic curve not only matches the seismic record well, but also has a good relationship with the sand bodies. Based on the analysis of geology, well logging, sedimentary facies, lithologic characteristics and geophysical parameters in the Daqingzijing Area of Shongliao Basin, the GR and SP data, which are obvious for the descriptiou of reservoir fithologic characteristics, are used to conduct the pseudo acoustic wave inversion for the seventh layer of the first member of Qingshankou Formation in three dimension working area. The GR inversion result is thought as the best to identify the sandstone-mudstone interface by comparing with the normal acoustic wave impedance inversion result. So the seventh layer sandstones are predicted by using the GR characteristic inversion and the predicted sand body thickness reaches 2 m resolution. The predicted thickness and plane distribution scope are almost consistent with the drilled wells, which provide a reliable geological reference for the determination of lithologie-struetural trap, rolling exploration and development well pattern design. And it also proves that the characteristic parameter inversion is practical in the development area with many wells. But it should be concerned that the characteristic parameter inversion would have the different application effects in different areas, and further verification and improvement need to be done.