摘要：Using the forced oscillation method and the ultrasonic transmission method, we measure the elastic moduli of a clay-bearing Thuringen sandstone under dry and water-saturated conditions in a broad frequency band at [0.004-10, 10(6)]Hz for different differential pressures up to 30MPa. Under water-saturated condition, clear dispersion and attenuation for Young's modulus, Poisson's ratio, and Bulk modulus are observed at seismic frequencies, except for shear modulus. The measured dispersion and attenuation are mainly attributed to the drained/undrained transition, which considers the experimentally undrained boundary condition. Gassmann's predictions are consistent with the measured undrained bulk moduli but not with the shear moduli. Clear shear weakening is observed, and this water-softening effect is stronger at seismic frequencies than at ultrasonic frequencies where stiffening effect related to squirt flow may mask real shear weakening. The reduction in surface free energy due to chemical interaction between pore fluid and rock frame, which is not taken into account by Gassmann's theory, is the main reason for the departure from Gassmann's predictions, especially for this rock containing a large number of clay minerals.

关键字：Low frequency experiments Gassmann's theory shear weakening Dispersion and attenuation Clay-bearing sandstone

ISSN号：2169-9313

卷、期、页：卷: 124 期: 2 页: 1254-1272

发表日期：2019-02-01

期刊分区（SCI为中科院分区）：二区

收录情况：SCI（科学引文索引印刷版）,ESI（基本科学指标数据库）,SCIE（科学引文索引网络版）

发表期刊名称：JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH

参与作者：Borgomano, Jan V. M.,Tiennot, Mathilde,Fortin, Jerome,Gueguen, Yves

通讯作者：殷晗钧

第一作者：王尚旭

论文类型：期刊论文

论文概要：殷晗钧,Borgomano, Jan V. M.,王尚旭,Tiennot, Mathilde,Fortin, Jerome,Gueguen, Yves，Fluid Substitution and Shear Weakening in Clay-Bearing Sandstone at Seismic Frequencies，JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH，2019，卷: 124 期: 2 页: 1254-1272

论文题目：Fluid Substitution and Shear Weakening in Clay-Bearing Sandstone at Seismic Frequencies