气候变化领域集成服务门户(CCPortal): The Thermal Diffusivity of Sedimentary Rocks: Empirical Validation of a Physically Based α − φ Relation

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DOI	10.1029/2020JB020595
	The Thermal Diffusivity of Sedimentary Rocks: Empirical Validation of a Physically Based α − φ Relation
	Fuchs S.; Förster H.-J.; Norden B.; Balling N.; Miele R.; Heckenbach E.; Förster A.
发表日期	2021
ISSN	21699313
卷号	126 期号:3
英文摘要	Understanding the thermal behavior of nonsteady state subsurface geosystems, when temperature changes over time, requires knowledge on the speed of heat propagation and, thus, of the rock's thermal diffusivity as essential thermo-physical parameter. Mixing models are commonly used to describe thermo-physical properties of polymineralic rocks. A thermal diffusivity-porosity relation is known from literature that incorporates common mixing models into the heat equation and properly works for unconsolidated, clastic clayey, and sandy marine sediments of high porosity (35%–80%). We have proofed the relation's applicability for consolidated, isotropic sedimentary rocks of low porosity (<35%). The performance of this approach was evaluated for consolidated quartz-dominated sandstones containing air, water, and heptane as pore- and/or fracture-filling medium. For these rocks, the reliability of the relation was confirmed for the entire range of porosity and all three media, with water-saturated rocks displaying an almost perfect fit between measured and modeled thermal diffusivity. Additional measurements conducted on a larger suite of low-porous siliciclastic and carbonate rocks imply that it is also suitable to acceptably good to infer the thermal diffusivity of mineralogically more diverse sedimentary rocks. In contrast to other common mixing models, this relation is appropriate to convert thermal-diffusivity data obtained on air-saturated samples into such reflecting water-saturated conditions. This is of particular importance for handling data acquired from methods limited to the measurement of dry samples, for example, laser-flash analysis. In conclusion, the applied relation is suited to model thermal-diffusivity data of isotropic sedimentary rocks of different porosity and independent of the pore fluid. © 2021. The Authors.
英文关键词	heat equation; mineral composition; mixing model; porosity; sedimentary rocks; specific heat capacity; thermal conductivity; thermal diffusivity
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/187278
作者单位	Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, Section 4.8 Geoenergy, Potsdam, Germany; Department of Geosciences, Aarhus University, Aarhus, Denmark; Now at CERENA, DECivil, Instituto Superior Técnico, Lisbon University, Lisbon, Portugal; Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences, Section 2.5 Geodynamic Modeling, Potsdam, Germany
推荐引用方式 GB/T 7714	Fuchs S.,Förster H.-J.,Norden B.,et al. The Thermal Diffusivity of Sedimentary Rocks: Empirical Validation of a Physically Based α − φ Relation[J],2021,126(3).
APA	Fuchs S..,Förster H.-J..,Norden B..,Balling N..,Miele R..,...&Förster A..(2021).The Thermal Diffusivity of Sedimentary Rocks: Empirical Validation of a Physically Based α − φ Relation.Journal of Geophysical Research: Solid Earth,126(3).
MLA	Fuchs S.,et al."The Thermal Diffusivity of Sedimentary Rocks: Empirical Validation of a Physically Based α − φ Relation".Journal of Geophysical Research: Solid Earth 126.3(2021).