薄互层油藏注水地震监测理论研究  

Seismic monitoring research on waterflooding in thin-interhedded reservoir

作　　者：云美厚[1] 易维启 陈卫军 张国富[2] 

机构地区：[1]大庆石油学院 [2]大庆石油管理局

出　　处：《石油地球物理勘探》1999年第6期723-732,共10页Oil Geophysical Prospecting

摘　　要：注水作为一种提高原油采收率的有效手段已被世界上许多油田所采用，但注水驱油效果的好坏在很大程度上取决于人们对注水动态的监控程度。本文借助于Gassmann方程就薄互层油藏注水地震监测的可能性进行了正演模拟分析，结果表明：砂岩孔隙率是决定注水地震监测成败的关键，砂岩孔隙率越高，越有利于注水地震监测的实施。对于不同的砂泥岩互层模型，只要砂岩孔隙率足够大，且砂岩总厚度足够大，利用地震方法进行注水动态监测是可行的。从地震响应结果发现，当孔隙率固定时，注水会引起反射同根轴的抬升，抬升幅度只与互层内砂岩总厚度有关，与互层总厚度无关，且注水砂岩总厚度越大，反射同根轴抬升越高，同时出现振幅异常。因此，其正演结果既可确定注水波及范围，又可定性或定量判定注水前缘位置及推进方向、推进速度等。Waterflooding, an effective means for improving oil recovery, are used in many oil fields all over the world. The waterflooding effect greatly depends on the monitoring of waterflooding. The possibility of seismically monitoring the waterflooding in thin interbed reservoir is analysed by making forward modeling with the use of Gassmann equation. Analysis result says that sand porosity is a key to successful or failing monitoring of waterflooding, higher sandstone porosity leading to better seismic monitoring of waterflooding. The modeling analysis of different sand-shale interbeds shows that when the porosity and total thickness of sandstone are high enough, it is possible for us to achieve seismic monitoring of waterflooding. The authors found from seismic responds that in the case of constant porosity, waterflooding uplifts reflection legs, and that the uplift amount has much to do with the totalthickness of sand layers in interbedded series but has nothing to do with the totalthickness of the interbedded series, bigger thickness of waterflooded sand layerscausing more obvlous uplift of reflection legs, with abnormal amplitude in this case. Thus, the forward modeling result helps reservoir engineer to determine waterflooding extent and to know qualitatively or quantitatively the location, advancedirection and advance velocity of waterfront.

关 键 词：薄层 动态监测 油藏 油田注水 驱油 地震监测 

分 类 号：TE357.6[石油与天然气工程—油气田开发工程]