Skip to Main content Skip to Navigation
Journal articles

Influence of Fluid Distribution on Seismic Dispersion and Attenuation in Partially Saturated Limestone

Abstract : Quantitatively assessing attenuation and dispersion of elastic-wave velocities in partially saturated reservoir is difficult because of its sensitivity to fluid distribution. We conducted experiments on homogeneous Indiana limestone samples, partially saturated by two methods: drying and imbibition which lead to different fluid distribution for a given saturation. Forced oscillations (from 0.004 to 100 Hz) and ultrasonic (1 MHz) measurements were done under confining pressure to measure the change of elastic moduli with frequency and their attenuation. Our measurements show that compressional (P-)velocities are strongly sensitive to the sample’s saturation method. For high saturations (above 80%), obtained by drainage, compressional velocities are frequency dependent, and clear peaks of attenuation can be observed. However, at the same saturations obtained by imbibition, no dispersion or attenuation is observed. In addition, shear velocities show little variation with frequency, saturations, and fluid distribution. The dispersion and attenuation of P-velocities are shown to be influenced by the pore fluid distribution, which was investigated using micro-computer-assisted tomographic (CT) scans. Furthermore, a numerical model developed within the framework of poroelasticity’s theory predicts well the experimental results, using the fluid distribution obtained from CT as an input. Our results show that the velocity dispersion was related to wave-induced fluid flow at mesoscopic scale controlled by the geometry and distribution of the gas patches.
Document type :
Journal articles
Complete list of metadata

https://hal-cnrs.archives-ouvertes.fr/hal-03766664
Contributor : Jerome Fortin Connect in order to contact the contributor
Submitted on : Thursday, September 1, 2022 - 12:15:40 PM
Last modification on : Saturday, September 3, 2022 - 3:51:05 AM

File

 Restricted access
To satisfy the distribution rights of the publisher, the document is embargoed until : 2022-10-21

Please log in to resquest access to the document

Identifiers

Collections

Citation

Chao Sun, Jérôme Fortin, Jan V M Borgomano, Shangxu Wang, Genyang Tang, et al.. Influence of Fluid Distribution on Seismic Dispersion and Attenuation in Partially Saturated Limestone. Journal of Geophysical Research : Solid Earth, American Geophysical Union, 2022, 127 (5), pp.e2021JB023867. ⟨10.1029/2021jb023867⟩. ⟨hal-03766664⟩

Share

Metrics

Record views

10