| Abstract |
Bhimband, a geothermal hotspot lies along the vast stretch of Munger- Saharsa Ridge fault zone bounded by the latitude 24.5:25.5N and longitude 85.0:86.75E of Eastern India. It has a geothermal potential of 60–65-degree Celsius with the highest surface manifestations temperature range with a cumulative flow rate of 1.2 to 5.5 l/sec. Our research focuses on the geochemical and geophysical surveys conducted in this region. The data obtained by conducting geochemical survey in the region suggests the presence of several elements and oxides in ppm. Bhimband is also distinguished by the presence of some trace elements like Cu, Zn, Pb and Ba in ppb. The pH of water in this region is 6.3 which suggests its slight acidic to neutral nature. The TDS is very low in the region. Based on this data some plots has been plotted in this research to elucidate the purpose of the suitability of the utilisation of geothermal water. These plots include, Piper plot, Wilcox and Durov plots. The geophysical survey in this study includes the acquisition and interpretation of gravity, magnetic and electrical resistivity data which shows the variation of density, magnetic susceptibility and conductivity respectively. In this research, the contour maps of the gravity and magnetic surveys shows the presence of four-way closure and doubly plunging saddle like features are indicative of geothermal reservoir. The gravity data varies from 3.6 to 7.2 mgals and the magnetic data varies from 37.3 nT to 71.9 nT. The electrical resistivity survey in the study area has been conducted using a 1-D resistivity metre, wenner survey method at a depth of 90 meter inferring the conductivity of the subsurface. By integrating all these surveys an integrated subsurface model can be prepared for a better understanding of the subsurface. Since, it can be observed that the area is a low- enthalpy geothermal zone, so, thermodynamic cycle like binary cycle can be incorporated by utilising a suitable working fluid in this geothermal system to generate power which can further be transmitted to the grid. In this process mechanical energy is converted into electrical energy. The existing literature suggests that the water present in this region is of mixed type as it includes the mixing of meteoric water with the parent water. Hence, the study suggests that Bhimband has sufficient potential for geothermal energy exploration and exploitation. |