摘要：Using the stress-strain oscillation method, we conducted experiments on a sandstone over a frequency range of 1-100 Hz at a differential pressure of 5 MPa to investigate the effects of oil saturation and oil/water substitution on modulus dispersion and attenuation. We first saturated the sandstone with a low viscosity oil (2#) at different saturation degrees, then replaced the 2# oil with a more viscous oil (68#) and finally injected distilled water in the oil-saturated sample. Young's modulus, Poisson's ratio and extensional attenuation were measured during these saturation processes. The measured moduli of this sandstone, when saturated with the 2# oil at different saturation degrees (0% to 100%) or when fully saturated with the 68# oil, manifest little dispersion over the frequency range of 1-100 Hz, and low attenuation was observed. The measured bulk modulus for the oil-saturated sandstone agrees well with the prediction of Gassmann's fluid-substitution theory, suggesting that wave-induced fluid flow (WIFF) plays an insignificant role in control of the bulk modulus when the sandstone is filled with oil. However, as oil saturation and viscosity increase, the shear modulus keeps increasing, violating the Gassmann's fluid-substitution theory, which may be caused by the viscous coupling mechanism. When water was injected into sandstone fully saturated with the 68# oil, distinct modulus dispersion and attenuation were observed. The characteristics of the modulus dispersion and attenuation are consistent with mesoscopic WIFF theory, indicating that mesoscopic WIFF is the main cause of modulus dispersion and attenuation for this sandstone saturated with oil-water mixture at seismic frequencies.

关键字：Rock physics low frequency dispersion attenuation saturation

ISSN号：0812-3985

卷、期、页：卷: 50 期: 3 页: 324-335

发表日期：2019-05-04

期刊分区（SCI为中科院分区）：四区

收录情况：SCIE（科学引文索引网络版）,ESI（基本科学指标数据库）,EI（工程索引）

发表期刊名称：EXPLORATION GEOPHYSICS

参与作者：Wang, Xingmou,Liu, Haojie,Wei, Guohua,Li, Minlong

通讯作者：赵立明

第一作者：唐跟阳,王尚旭,赵建国,孙超,杨立敏

论文类型：期刊论文

论文概要：赵立明,唐跟阳,王尚旭,赵建国,Wang, Xingmou,Liu, Haojie,Wei, Guohua,孙超,Li, Minlong,杨立敏，Laboratory study of oil saturation and oil/water substitution effects on a sandstone's modulus dispersion and attenuation，EXPLORATION GEOPHYSICS，2019，卷: 50 期: 3 页: 324-335

论文题目：Laboratory study of oil saturation and oil/water substitution effects on a sandstone's modulus dispersion and attenuation