气候变化领域集成服务门户(CCPortal): The Power-Law Relation Between Inclusion Aspect Ratio and Porosity: Implications for Electrical and Elastic Modeling

CCPortal

DOI	10.1029/2019JB019187
	The Power-Law Relation Between Inclusion Aspect Ratio and Porosity: Implications for Electrical and Elastic Modeling
	Cilli P.A.; Chapman M.
发表日期	2020
ISSN	21699313
卷号	125 期号:5
英文摘要	Geophysicists depend on rock physics relationships to interpret resistivity and seismic velocity in terms of rock porosity, but it has proven difficult to capture the effect of pore geometry on such relations through simple and easy to apply formulae. Inclusion modeling relates moduli to porosity through an equivalent grain or pore aspect ratio but often fails to account for observed trends, whereas empirical relations can be hard to extrapolate beyond their range of validity, often giving incorrect results in the low and high porosity limits. We show that introducing a power-law relationship between porosity and equivalent grain or pore aspect ratio allows inclusion models to reproduce five published empirical resistivity-porosity and velocity-porosity relationships, providing a first principles basis for extrapolation to other cases of interest. We find that the deviation of resistivity from Archie's law in carbonates is related to a systematic change of grain shape with porosity, and we derive a new relation that fits carbonate resistivity data with similar accuracy to the Humble equation while being correct at high porosity. We then obtain an analog for the Castagna and Pickett relationships for wet, calcitic rocks, which is valid in the low and high porosity limits, giving rise to a new, physically derived Vp/Vs versus porosity model. ©2020. The Authors.
英文关键词	carbonates; elastic properties; electrical properties; inclusion model; power-law; rock physics
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/187848
作者单位	Grant Institute, School of GeoSciences, University of Edinburgh, Edinburgh, United Kingdom; International Centre for Carbonate Reservoirs, Edinburgh, United Kingdom; Now at Department of Earth Sciences, University of Oxford, Oxford, United Kingdom
推荐引用方式 GB/T 7714	Cilli P.A.,Chapman M.. The Power-Law Relation Between Inclusion Aspect Ratio and Porosity: Implications for Electrical and Elastic Modeling[J],2020,125(5).
APA	Cilli P.A.,&Chapman M..(2020).The Power-Law Relation Between Inclusion Aspect Ratio and Porosity: Implications for Electrical and Elastic Modeling.Journal of Geophysical Research: Solid Earth,125(5).
MLA	Cilli P.A.,et al."The Power-Law Relation Between Inclusion Aspect Ratio and Porosity: Implications for Electrical and Elastic Modeling".Journal of Geophysical Research: Solid Earth 125.5(2020).