气候变化领域集成服务门户(CCPortal): Negative Unjacketed Pore Modulus in Limestones? Critical Examination of a Peculiar Laboratory Observation

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DOI	10.1029/2020JB020525
	Negative Unjacketed Pore Modulus in Limestones? Critical Examination of a Peculiar Laboratory Observation
	Tan W.; Müller T.M.; Ba J.
发表日期	2021
ISSN	21699313
卷号	126 期号:2
英文摘要	There is recent experimental evidence that the effective pressure coefficient for pore volume exceeds unity in limestones with dual porosity structure. Within the realm of linear poroelastcity, this means that the unjacketed pore modulus is negative. This would be a rather unusual rock behavior since it implies that the pore volume increases for a positive pressure increment during hydrostatic compression. Generally, any deviation of the unjacketed pore modulus from strictly positive mineral bulk modulus means that the deformation is inhomogeneous. We critically examine these observations by attempting to reconcile them with the poroelastic constitutive equations of micro-inhomogeneous rocks that encompass inhomogeneous deformations. Consistency checks among measured poroelastic constants reveal that the measurement accuracy of pore volume changes concurring with the deformation experiments is not as high as desired. However, assigning moderate variations to the measured pore volume changes either due to random or systematic measurement errors, we show that the experimental observations are indeed reconcilable with the constitutive poroelastic equations. Hence, the negative unjacketed pore modulus observed is deemed plausible though overestimated. Within the poroelasticity framework for micro-inhomogeneous rocks, a negative unjacketed pore modulus is the result of a partial localization of elastic strain energy in the fluid space. This in turn could be caused by dissolved calcite particles that block thin pore throats and thus generate temporary fluid pressure compartmentalization. A far-reaching consequence of a negative unjacketed pore modulus is that description of the undrained bulk modulus in rocks with dual porosity structure is more complicated than previously thought. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	Effective stress coefficient; experiment; micro-inhomogeneous; poroelasticity; unjacketed pore modulus
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/187337
作者单位	School of Earth Sciences and Engineering, Hohai University, Nanjing, China; Department of Exploration Geophysics, Curtin University, Perth, WA, Australia; Department of Seismology, Centro de Investigación Científica y de Educación Superior de Ensenada, Enseneda, Mexico
推荐引用方式 GB/T 7714	Tan W.,Müller T.M.,Ba J.. Negative Unjacketed Pore Modulus in Limestones? Critical Examination of a Peculiar Laboratory Observation[J],2021,126(2).
APA	Tan W.,Müller T.M.,&Ba J..(2021).Negative Unjacketed Pore Modulus in Limestones? Critical Examination of a Peculiar Laboratory Observation.Journal of Geophysical Research: Solid Earth,126(2).
MLA	Tan W.,et al."Negative Unjacketed Pore Modulus in Limestones? Critical Examination of a Peculiar Laboratory Observation".Journal of Geophysical Research: Solid Earth 126.2(2021).