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DOI	10.5194/hess-23-3305-2019
	The effect of sediment thermal conductivity on vertical groundwater flux estimates
	Sebok E.; Müller S.
发表日期	2019
ISSN	1027-5606
起始页码	3305
结束页码	3317
卷号	23 期号:8
英文摘要	Vertical sediment temperature profiles are frequently used to estimate vertical fluid fluxes. In these applications using heat as a tracer of groundwater flow, the thermal conductivity of saturated sediments (ke) is often given as a standard literature value and assumed to have a homogeneous distribution in the vertical space. In this study vertical sediment temperature profiles were collected in both a highflux stream and a low-flux lagoon environment in sand- and peat-covered areas. ke was measured at the location of each temperature profile at several depths below the sediment- water interface up to 0.5m with a measurement spacing of 0.1 m. In general ke values measured in this study ranged between 0.55 and 2.96Wm-1 °C-1 with an increase with depth from the sediment-water interface. The effect of using a vertically homogeneous or heterogeneous distribution of measured ke values on vertical flux estimates was studied with a steady-state HydroGeoSphere model. In the high-flux stream environment estimated fluxes varied between 0.03 and 0.71md-1 and in the low-flux lagoon between 0.02 and 0.23md-1. We found that using a vertically heterogeneous distribution of sediment thermal conductivity did not considerably change the fit between observed and simulated temperature data compared to a homogeneous distribution of ke. However, depending on the choice of sediment thermal conductivities, flux estimates decreased by up to 64% or increased by up to 75% compared to using a standard ke sediment thermal conductivity for sand, frequently assumed by previous local studies. Hence, our study emphasizes the importance of using spatially distributed thermal properties in heat flux applications in order to obtain more precise flux estimates. © Author(s) 2019.
语种	英语
scopus关键词	Groundwater; Groundwater flow; Heat flux; Sediments; Temperature control; Groundwater fluxes; Heterogeneous distributions; Homogeneous distribution; Lagoon environments; Saturated sediments; Sediment water interface; Stream environment; Temperature profiles; Thermal conductivity; flux measurement; groundwater flow; lagoon; sediment property; sediment-water interface; temperature profile; thermal conductivity; tracer; vertical movement
来源期刊	Hydrology and Earth System Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/159631
作者单位	Sebok, E., Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, Copenhagen, 1350, Denmark; Müller, S., Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, Copenhagen, 1350, Denmark
推荐引用方式 GB/T 7714	Sebok E.,Müller S.. The effect of sediment thermal conductivity on vertical groundwater flux estimates[J],2019,23(8).
APA	Sebok E.,&Müller S..(2019).The effect of sediment thermal conductivity on vertical groundwater flux estimates.Hydrology and Earth System Sciences,23(8).
MLA	Sebok E.,et al."The effect of sediment thermal conductivity on vertical groundwater flux estimates".Hydrology and Earth System Sciences 23.8(2019).