Electrical Resistivity Tomography and TDEM Applied to Hydrogeological Study in Taubaté Basin, Brazil

Abstract

This research applies Electrical Resistivity Tomography (ERT) and Time Domain Electromagnetic Method (TDEM) to study the hydrogeology of the Taubaté basin, which is characterized by half-grabens with about 850 m of maximum sediments thickness. The study area is in Taubaté city, São Paulo State, Brazil, where the Taubaté aquifer is an important water source. The Taubaté Group is the main sedimentary package of the basin; it is formed mainly by shales that form aquicludes, and thin layers of sandstones that form the aquifer. There are 40 groundwater exploration wells in Taubaté city that provide important information. The study purpose is to characterize the geoelectrical stratigraphy of the subsurface to locate the contact between the Quaternary and Tertiary sediments and to identify the Taubaté aquifer. The ERT is used for shallow investigations (tens of meters) and the TDEM can reach a great investigation depth (hundreds of meters). Therefore, these geo- The TDEM method defined the Taubaté Group as a single geoelectric layer because the shale and the sandstone layers are all very conductive. The basement is formed by gneiss, which is a very resistive rock. The TDEM method is not able to identify a high conductor/resistor contrast. Overall, the results are

The Use of Electrical Resistivity Tomography and Time Domain Electromagnetic Methods to Investigate the Superficial Deposits at Al al-Bayt University, Jordan as a Case Study

“…The Electrical Resistivity Tomography (ERT) technique is used in shallow applications around tens of meters, while the Time Domain Electromagnetic method (TDEM) technique is used for deep applications around hundreds of meters, and it can detect layers of different conductivities (McNeill,1994;Christiansen et al, 2006;Rangel et al, 2018). The ERT method is considered as a strong tool to study subsurface geological features for different engineering, geotechnical, and environmental applications (Al Amoush and Abu Rajab, 2018;Olasunkanmi et al, 2021).…”

Application of Aquifer Delineation and Hydrogeophysical Techniques in Estimating Groundwater Recharge to Enhance Water Allocation in Groundwater-Dependent Areas, Northern Cape, South Africa

“…Besides its limitations, the electrical resistivity method can provide detailed information about subsurface layer variations [13]. The method has the potential to identify subsurface structures, aquicludes, and aquitards, which normally are more conductive than the surrounding layers and are sensitive to geological properties, like clay content [14].…”

Investigação de Depósitos Auríferos no Quadrilátero Ferrífero, MG, Por Meio da Análise de Dados HTEM

“…The TEM method or Time Domain Electromagnetic (TDEM) method is an inductive electromagnetic (EM) method used to map the electrical conductivity (or resistivity) contrast in subsurface. The method is quite versatile and finds applications in the mineral exploration (Oliveira, 2014;Couto et al, 2016;Viezzoli et al, 2016;Couto et al, 2017b;Oliveira, 2020), hydrogeology investigation (Danielsen, et al, 2002;Porsani et al, 2012aPorsani et al, , 2012bBortolozo et al, 2014;Bortolozo et al, 2015;Almeida, et al, 2017;Campaña, et al, 2017;Hamada, et al, 2018;Leite, et al, 2018;Rangel, et al, 2018).The TEM methodology was developed in face of the difficulties in the applications of the Frequency Domain Electromagnetic (FDEM) method, which the induction of the EM field in subsurface (secondary field) is generated through an alternate current (AC) within a transmitter loop (Tx) on surface and the secondary field is measured through a receiver coil (Rx) still in the presence of the primary field generated by the current in Tx (Figure 3. 1-a).…”