松辽盆地杏山地区深部火山岩有利储层的控制因素及分布预测

Controlling Factors and Distribution Prediction of Deep-buried Favorable Volcanic Reservoir in the Xingshan Area of Songliao Basin

深层火山岩储层研究是松辽盆地油气勘探的新领域。地球化学和岩石学研究表明,与松辽盆地南部深层火山岩相比,盆地北部杏山地区营城组的火山岩以中酸性喷出岩类为主,其中灰白色流纹岩中的原生气孔、风化溶蚀孔和构造裂缝为较好的储集空间。利用常规测井资料可以对火山岩岩性进行较好的识别,结合成像测井资料可以较好地描述和预测裂缝—孔隙性储层。研究表明:常规测井解释的裂缝孔隙度、产状以及预测结果与成像和取心结果符合较好;近火山口有利岩相带中,风化淋滤溶蚀作用和构造裂缝是营城组火山岩储层形成有利储集空间的主要控制因素。利用测井约束地震反演预测的3种火山岩体参数(火山岩厚度、上覆盖层厚度和构造曲率)进行叠合可以较好地预测火山岩优质储层的空间分布特征。结合有利相带、储集空间类型以及储层物性特征,提出了研究区火山岩储层的综合分类评价标准。将营城组火山岩储层划分为3类,预测出8个有利储层发育区,其预测结果与实际钻井和测试数据符合较好,为本区的深部天然气勘探指明了方向。

The research on deep-buried volcanic reservoir is an important new field of oil and gas exploration in Songliao Basin. Geochemical and petrological research proves that neutral and acid extrusive volcanic rock is the major type of volcanic rocks in Yingcheng Formation, Xingshan area, compared with that of south part of this basin. In ryolite, the gas pores, dissolved pores caused by efflorescence as well as structural fracture are favora- ble reservoir spaces. Core analysis shows that relationship between porosity and permeability is different in dif- ferent areas, so does the heterogeneity. Different volcanic lithologies can be well identified with imaging well logging with conventional logging data, and it＇s possible to describe and predict porous and fractural reservoir. Lateral resistivity is used to predict the porosity and architecture of fracture, which coincides well with the ima- ging logging data and core describing. Favorable volcanic facies, efflorescence and structural fracture are three major controlling factors of favorable volcanic reservoir. Under the direction of these major controlling factors, three kinds of volcanic rock body parameters （volcanic thickness, seal thickness and structural curvature） achieved by log restricted seismic inversion, favorable facies, the type of reservoir spaces and physical property of reservoir, volcanic reservoir of Yingcheng Formatioin in the research area can be divided into three types and eight favorable distribution areas of reservoir can be predicted. The results are consistent with drilling and testing data very well, and provide direction for exploration of deep volcanic reservoir.