松辽盆地古龙页岩跨频带岩石物理测量

Cross-band petrophysical measurements of Gulong shale in Songliao Basin

松辽盆地古龙页岩为典型的陆相淡水湖盆沉积,特殊的沉积环境造就了古龙页岩具有不同于其他盆地的独特矿物组成、演化程度和微观结构,其弹性也必然异于其他页岩地层。为了研究古龙页岩岩石物理声学特征及影响因素,开展了包括跨频带岩石物理声学测量、有机质热解、扫描电镜、全岩衍射分析等实验测试和数据分析,研究古龙页岩在不同方向的纵横波速度、各向异性参数及频散衰减属性的变化规律。结果表明:古龙页岩具有高于其他盆地页岩地层的强各向异性和高频散高衰减岩石物理特征,这一独特的特征与古龙页岩的黏土矿物含量及定向排列程度、页理发育程度、有机质含量及成熟度、孔隙度等因素密切相关。研究结果揭示了古龙页岩岩石物理声学特征和影响因素,能够为古龙页岩油地震成像处理及富集层预测提供理论依据和数据支撑。

Gulong shale in Songliao Basin is typical continental freshwater lake-basin deposit.The special depositional environment created Gulong shale with unique mineral compositions,evolution degree and microstructure different from other basins,and necessarily different elastic property.In order to study petrophysical acoustic characteristics and their influencing factors of shale in Gulong,lab tests and data analyses including cross-band petrophysical acoustic measurement,organic matter pyrolysis,SEM and whole-rock diffraction analysis are performed and studied the rule of velocity variation patterns of P-wave and S-wave in different direction,the anisotropy and the dispersion-attenuation.The results show that Gulong shale has petrophysical characteristics of stronger anisotropy,higher frequency dispersion and higher attenuation than those in other basins.This unique characteristics is closely related to claymineral content and oriented alignment,lamellation developed degree,organic matter content and maturity,porosity of Gulong shale.The research conclusion reveals the petrophysical acoustic characteristics and influencing factors of Gulong shale,which can provide theoretical basis and data support for seismic imaging processing and enrichment layer prediction of Gulong shale oil.