气候变化领域集成服务门户(CCPortal): Constraining Microfractures in Foliated Alpine Fault Rocks With Laser Ultrasonics

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DOI	10.1029/2020GL087378
	Constraining Microfractures in Foliated Alpine Fault Rocks With Laser Ultrasonics
	Simpson J.; Adam L.; van Wijk K.; Charoensawan J.
发表日期	2020
ISSN	0094-8276
卷号	47 期号:8
英文摘要	Quantifying the amount and alignment of microfractures is important to understand the geomechanics, fluid flow, and seismic imaging of fault zones. At the Alpine Fault, New Zealand, the preferred alignment of minerals, foliation, and fractures results in elastic wave anisotropy. We have designed a unique laser-ultrasonic laboratory setup to study Alpine Fault rock samples at upper crustal conditions. Combined with differential effective medium modeling, we distinguish microfracture porosity and orientation from mineral alignment, as a function of distance to the principal slip zone (PSZ). Nearest to the PSZ, the cataclasite has the lowest P wave anisotropy with the most (randomly oriented) fractures. Next, the ultramylonite exhibits the greatest P wave anisotropy (∼45%) with 40% of its fractures aligned with foliation. Further from the PSZ, P wave anisotropy is 14–19% on average, due to 20–30% of the fractures being oriented in the same direction as mineral alignment. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Alignment; Anisotropy; Flow of fluids; Fracture; Minerals; Ultrasonics; Alpine Faults; Differential effective mediums; Laboratory set-up; Laser ultrasonics; Micro-fracture; Microfractures; Seismic imaging; Ultramylonite; Seismic waves; alpine environment; elastic wave; fault plane; foliation; fracture; geomechanics; imaging method; laser method; P-wave; seismic anisotropy; ultrasonics; upper crust; New Zealand
语种	英语
来源期刊	Geophysical Research Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/170468
作者单位	Dodd-Walls Centre for Photonic and Quantum Technologies and The Physical Acoustics Laboratory, Department of Physics, University of Auckland, Auckland, New Zealand; Physics of Rocks Laboratory, School of Environment, University of Auckland, Auckland, New Zealand
推荐引用方式 GB/T 7714	Simpson J.,Adam L.,van Wijk K.,et al. Constraining Microfractures in Foliated Alpine Fault Rocks With Laser Ultrasonics[J],2020,47(8).
APA	Simpson J.,Adam L.,van Wijk K.,&Charoensawan J..(2020).Constraining Microfractures in Foliated Alpine Fault Rocks With Laser Ultrasonics.Geophysical Research Letters,47(8).
MLA	Simpson J.,et al."Constraining Microfractures in Foliated Alpine Fault Rocks With Laser Ultrasonics".Geophysical Research Letters 47.8(2020).