3D modelling of combination of array results for resistivity profiling data over a dyke for groundwater exploration and
- PDF / 1,210,601 Bytes
- 10 Pages / 595.276 x 790.866 pts Page_size
- 21 Downloads / 158 Views
ORIGINAL ARTICLE
3D modelling of combination of array results for resistivity profiling data over a dyke for groundwater exploration and development Dewashish Kumar1 · N. S. Krishnamurthy1 Received: 15 November 2019 / Accepted: 11 August 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Detailed three-dimensional (3D) modelling of resistivity profiling data collected across the long outcropping in situ dyke with significant width ~ 25–30 m and intruded within the granite host rock was performed to evaluate the resistivity anomaly response, understand the dyke characteristics properties and its role in groundwater flow. The main objective of the present research work is to develop information about the subsurface and explain the observed anomaly/data, confirm the resistivity anomaly response using two different electrode configurations, namely, Wenner and Schlumberger. Interpretation of the 3D modelling results indicate high resistivity anomaly over the in situ dyke. The extent of degree of weathering of rocks (here, granite) is quite and clearly visible from the anomaly responses in model output in terms of resistivity contrasts. The results are fairly well in agreement with the field resistivity anomaly especially in terms of shape of the anomaly. The 3D theoretical forward modelling approach performed using resistivity profiling data set is much helpful and significant in establishing the knowledge of true anomaly caused due to subsurface dyke in the present geological set up. It resolved the shape and width of the dyke both laterally and vertically. The degree of weathering of dyke near the surface is well resolved. The comparison of the modelling results with the field data gives a strong correlation between resistive anomalies and the subsurface. The study is very useful for groundwater exploration and development and helps us to understand precisely the role of dyke based on the 3D modelling study. Keywords Dyke · Resistivity profiling · 3D modelling · Resistivity anomalies · Granite terrain · India
Introduction Resistivity profiling in one of the geoelectrical method, which is commonly used for groundwater exploration and prospecting in groundwater hydrogeology. But using the combination of arrays has added advantage over single array method in delineating the resistivity of the subsurface anomaly as an indirect indicator of groundwater especially in hard rock terrain, where inherent large variability of physical parameters and heterogeneity exists. Resistivity survey using Wenner and Schlumberger configurations over dolerite and metadolerite dykes have been carried out to find the potentiality for water accumulation (Singh and Jha 1972; Kumar 2004). According to them these dykes gave rise both high and low resistivity anomaly as compared to the * Dewashish Kumar [email protected] 1
CSIR-National Geophysical Research Institute, Hyderabad 500007, India
host rock and the suitable sites for groundwater have been delineated. Resistivity survey with three Wenner configur
Data Loading...
