Hydrothermal Reservoir and Electrical Anisotropy Investigated by Magnetotelluric Data, Case Study of Asal Rift, Republic of Djibouti

At the center of Republic Djibouti, an eroded rift called Asal is located where tectonic and magmatic activities can be observed at surface. Multiple studies were carried out with different exploration methods, such as structural, geophysical hydrogeological, to understand rifting processes characterize subsurface this rift. Among these deep geoelectrical structures need better defined magnetotelluric (MT) method delineate resistivity structures. With objective improving our understanding structure, data acquired in analyzed inverted build a 2D electrical conductivity model hydrothermal system. To achieve this, dimensionality analysis MT along profile perpendicular axis was out. Results justify approximation structure. Then, inversion models achieved conductive Dimensionality results revealed existence anisotropy. Consistent correlation between geoelectric strike anisotropy direction suggested. Electrical determined from ellipticity phase tensor for short periods interpreted consequence activity horizontal deformation Moreover, long assumed related effects combined magmatic-tectonic predominant magma/dyke intrusion, which implies vertical subsidence may imply alignment Olivine. variation rotation paleo recent stress fields plate motion junction three diverging plates—Arabia, Nubia Somalia—over geological time generate both turn induce preferred highest conductivity. While north-south parallel Red Sea Rift propagation, north-east aligned extension Arabia Somalia plates. presented allowed identify two superimposed units close surface are shallow aquifer wide potential These mediums overlying relatively resistive medium. The latter associated system likely containing hot and/or partly molten rocks. developed study could considered conceptual prior modeling multiphase fluid flow heat transfer used future drilling target depth geothermal exploration.