气候变化领域集成服务门户(CCPortal): Seismic Diffusivity and the Influence of Heterogeneity on Injection-Induced Seismicity

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DOI	10.1029/2021JB021768
	Seismic Diffusivity and the Influence of Heterogeneity on Injection-Induced Seismicity
	Haagenson R.; Rajaram H.
发表日期	2021
ISSN	21699313
卷号	126 期号:6
英文摘要	The spatiotemporal patterns of injection-induced seismicity (IIS) are commonly interpreted with the concept of a triggering front, which propagates in a diffusion-like manner with an associated diffusivity parameter. Here, we refer to this diffusivity as the “seismic diffusivity.” Several previous studies implicitly assume that seismic diffusivity is equivalent to the effective hydraulic diffusivity of the subsurface, which describes the behavior of the mean pressure field in heterogeneous porous media. Seismicity-based approaches for hydraulic characterization or simulations of IIS using domains of homogeneous equivalent porous media are implicitly based on this assumed equivalence. However, seismicity is expected to propagate with the threshold triggering pressure, and thus not be controlled by the evolution of the mean pressure field. We present numerical simulations of fluid injection to compare the seismic and effective hydraulic diffusivities in heterogeneous formations (including fractured rock). The numerical model combines uncoupled, linear pressure diffusion with the Mohr-Coulomb failure criterion to simulate IIS. We demonstrate that connected pathways of relatively high hydraulic diffusivity in heterogeneous media (particularly in fractured rock domains) allow the threshold triggering pressure to propagate more rapidly than predicted by the effective hydraulic diffusivity. As a result, the seismic diffusivity is greater than the effective hydraulic diffusivity in heterogeneous porous media, possibly by an order of magnitude or more. Additionally, we present a case study of IIS near Soultz-sous-Forêts where seismic diffusivity is found to be at least one order of magnitude larger than the effective hydraulic diffusivity. © 2021. The Authors.
英文关键词	enhanced geothermal systems; fractured porous media; injection-induced seismicity; subsurface modeling
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/187072
作者单位	Environmental Health and Engineering, Johns Hopkins University, Baltimore, MD, United States; Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, Boulder, CO, United States
推荐引用方式 GB/T 7714	Haagenson R.,Rajaram H.. Seismic Diffusivity and the Influence of Heterogeneity on Injection-Induced Seismicity[J],2021,126(6).
APA	Haagenson R.,&Rajaram H..(2021).Seismic Diffusivity and the Influence of Heterogeneity on Injection-Induced Seismicity.Journal of Geophysical Research: Solid Earth,126(6).
MLA	Haagenson R.,et al."Seismic Diffusivity and the Influence of Heterogeneity on Injection-Induced Seismicity".Journal of Geophysical Research: Solid Earth 126.6(2021).