气候变化领域集成服务门户(CCPortal): Laboratory Investigations of Acoustic Anisotropy in Artificial Porous Rock With Aligned Fractures During Gas Hydrate Formation and Dissociation

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DOI	10.1029/2021JB021678
	Laboratory Investigations of Acoustic Anisotropy in Artificial Porous Rock With Aligned Fractures During Gas Hydrate Formation and Dissociation
	Liu S.; Han T.; Fu L.-Y.
发表日期	2021
ISSN	21699313
卷号	126 期号:4
英文摘要	Fractures can widely exist in hydrate-bearing reservoirs and can give rise to anisotropic acoustic properties that play an important role in the accurate assessment of fractured reservoirs. However, the knowledge of the responses of acoustic anisotropy in fractured hydrate-bearing reservoirs is still poorly understood. To obtain such understanding, we designed and implemented dedicated laboratory experiments to measure the anisotropic acoustic velocities in an artificial sandstone with aligned penny-shaped fractures parallel to the layers during hydrate formation and dissociation at the confining pressures of 20 and 50 MPa, respectively. We showed that although the velocities at higher confining pressure were systematically greater, all the velocities at both confining pressures increased and decreased during hydrate formation and dissociation, respectively. We also showed that the velocities during hydrate formation were significantly higher than those during dissociation at hydrate saturation greater than 10%. It was found that all the velocities smoothly reduced with decreasing saturation during dissociation, while the varying velocities exhibited distinct increasing gradients during formation, where the compressional wave anisotropy reduced dramatically at saturation between 10% and 25%. Analyses of the experimental results suggested that the floating hydrate evolved to bridge the surfaces of fractures when hydrate saturation exceeded 10% during hydrate formation, and the bridging hydrate gradually transformed to floating in the pore system during dissociation. The results provide new insights into hydrate distribution and its effects on acoustic anisotropy in fractured reservoirs during hydrate formation and dissociation and will contribute to improving the accuracy of hydrate assessment in such reservoirs. © 2021. American Geophysical Union. All Rights Reserved.
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187233
作者单位	School of Geosciences, China University of Petroleum (East China), Qingdao, China; Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
推荐引用方式 GB/T 7714	Liu S.,Han T.,Fu L.-Y.. Laboratory Investigations of Acoustic Anisotropy in Artificial Porous Rock With Aligned Fractures During Gas Hydrate Formation and Dissociation[J],2021,126(4).
APA	Liu S.,Han T.,&Fu L.-Y..(2021).Laboratory Investigations of Acoustic Anisotropy in Artificial Porous Rock With Aligned Fractures During Gas Hydrate Formation and Dissociation.Journal of Geophysical Research: Solid Earth,126(4).
MLA	Liu S.,et al."Laboratory Investigations of Acoustic Anisotropy in Artificial Porous Rock With Aligned Fractures During Gas Hydrate Formation and Dissociation".Journal of Geophysical Research: Solid Earth 126.4(2021).