The calculation of apparent resistivity in electrical methods is relatively simple and consolidated in the literature. Furthermore, in the case of DC methods, the apparent resistivity values are for the most part, int...The calculation of apparent resistivity in electrical methods is relatively simple and consolidated in the literature. Furthermore, in the case of DC methods, the apparent resistivity values are for the most part, intuitive and enable an initial interpretation of the results. On the other hand, in TEM method the apparent resistivity values are not very intuitive and interpretation based only on the apparent resistivity values cannot be done reasonably. In this way, this paper presents a discussion about the reasons and effects of the negatives values of apparent resistivity in TEM soundings. The main objective of this paper is to clarify the meanings of these negatives values and the possible effects in TEM inversion.展开更多
Resistivity is used to evaluate soil water content(SWC),which has the advantages of not causing soil disturbance and in low price.It is an effective way to assess the SWC variability.This paper aims to evaluate the va...Resistivity is used to evaluate soil water content(SWC),which has the advantages of not causing soil disturbance and in low price.It is an effective way to assess the SWC variability.This paper aims to evaluate the variability of loess slope SWC through the change of resistivity.It provides a simple way for long term SWC monitoring to solve the expensive cost of deploying moisture sensors.In this context,geoelectric and environmental factors such as soil temperature and SWC were monitored for three years.The prediction model of apparent resistivity and SWC was calibrated.The post processing of geoelectric data was introduced.In addition,the SWC collected by Time-Domain Reflectometry(TDR)was used to verify the feasibility of electrical resistivity tomography(ERT)data.The SWC variability in the process of rainfall,the evolution of four seasons,and the alternation of drying and wetting were evaluated.The research results show that:i)the SWC monitored by ERT and TDR can reflect the response and hysteretic effect of water content at 0.5-3.0 m depth.ii)The moisture content monitored by ERT reflects that the soil is relatively wet in summer and autumn and dry in winter and spring.iii)From 2017 to 2020,the SWC increased in August,and the soil became dry in January.iv)Two areas with high SWC and three areas with low SWC on loess slope are reflected by resistivity.The outcome can provide the change information of SWC to a great extent without excavating boreholes.展开更多
文摘The calculation of apparent resistivity in electrical methods is relatively simple and consolidated in the literature. Furthermore, in the case of DC methods, the apparent resistivity values are for the most part, intuitive and enable an initial interpretation of the results. On the other hand, in TEM method the apparent resistivity values are not very intuitive and interpretation based only on the apparent resistivity values cannot be done reasonably. In this way, this paper presents a discussion about the reasons and effects of the negatives values of apparent resistivity in TEM soundings. The main objective of this paper is to clarify the meanings of these negatives values and the possible effects in TEM inversion.
基金supported by the National Natural Science Foundation of China(Grant Nos:42107209and 41530640)the National Key Research and Development Program of China(Grant No:2018YFC1504701)。
文摘Resistivity is used to evaluate soil water content(SWC),which has the advantages of not causing soil disturbance and in low price.It is an effective way to assess the SWC variability.This paper aims to evaluate the variability of loess slope SWC through the change of resistivity.It provides a simple way for long term SWC monitoring to solve the expensive cost of deploying moisture sensors.In this context,geoelectric and environmental factors such as soil temperature and SWC were monitored for three years.The prediction model of apparent resistivity and SWC was calibrated.The post processing of geoelectric data was introduced.In addition,the SWC collected by Time-Domain Reflectometry(TDR)was used to verify the feasibility of electrical resistivity tomography(ERT)data.The SWC variability in the process of rainfall,the evolution of four seasons,and the alternation of drying and wetting were evaluated.The research results show that:i)the SWC monitored by ERT and TDR can reflect the response and hysteretic effect of water content at 0.5-3.0 m depth.ii)The moisture content monitored by ERT reflects that the soil is relatively wet in summer and autumn and dry in winter and spring.iii)From 2017 to 2020,the SWC increased in August,and the soil became dry in January.iv)Two areas with high SWC and three areas with low SWC on loess slope are reflected by resistivity.The outcome can provide the change information of SWC to a great extent without excavating boreholes.
基金National Basic Research Program of China(2015CB150502)National Natural Science Foundation of China(31172032)Special Fund for Agro-scientific Research in the Public Interest of China(201003016)