Diffusion of an electromagnetic pulse in a heterogeneous earth

Verma, Saurabh

doi:10.1007/bfb0011931

Cited by 1 publication

(2 citation statements)

References 33 publications

(47 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This thin layer is hydrogeologically referred to as an unconfined aquifer unit, similar to other studies, e.g., [13]. However, because of some technical limitations, i.e., the input current turn-off time depends on the transmitter moment, which affects the TEM method's minimum detection depth [30,35], we are not confident in interpreting this layer. The low-resistivity material 6-40 Ohm-m is found at about 10-50 m depth.…”

Section: Tem 1d Modelsmentioning

confidence: 60%

“…Secondary magnetic fields due to the induced currents continue while the primary field is intentionally turned off. The coil sensor on the surface measures the voltage transient produced by the secondary magnetic field, which is linked with the subsurface material's resistivity variation [25,30]. Theoretically, the sensor opens its gate once the primary magnetic field is turned off.…”

Section: Principle Of Time Domain Electromagnetic Methods (Tem)mentioning

confidence: 99%

See 1 more Smart Citation

Mapping Hydrogeological Structures Using Transient Electromagnetic Method: A Case Study of the Choushui River Alluvial Fan in Yunlin, Taiwan

Kassie

Chang

Zeng

et al. 2023

Water

View full text Add to dashboard Cite

We used transient electromagnetic (TEM) to map the hydrogeological structures in the Choushui River Alluvial Fan in Yunlin County of central Taiwan. A total of 63 TEM measurements were collected using the FASTSNAP system with 50 × 50 m in-loop configurations in the middle and distal fan. The 1D model, based on prior information, was constructed from the inverted soundings. Results showed a thin, resistive shallow layer and a 40 m low-resistive (6–42 ohm-m) zone beneath it. High-resistive zones (50–170 ohm-m) were found from 50–120 m depth, and low-resistive zones were revealed below 120 m in some areas. Results were consistent with resistivity and lithology logs from nearby wells. The inverted TEM models provide reliable subsurface information when prior informations of vertical electrical sounding and TEM were considered. We interpolated resistivity at 10 m, 50 m, 100 m, and 160 m depth from the 1D model results to produce a slice map of the area, which indicated variations, trends, and depths of the sediment deposits. The TEM method successfully identified the hydrogeological structures, showing that the upper 40 m of sediment acts as a confining layer for the aquifer structure from 50 m to 120 m depth.

show abstract

Section: Tem 1d Modelsmentioning

confidence: 60%

Section: Principle Of Time Domain Electromagnetic Methods (Tem)mentioning

confidence: 99%