An Assessment of the Geothermal Potential of Bangladesh

In Bangladesh, many deep abandoned wells, originally drilled for oil and gas exploration, have been used to extract valuable information about the subsurface geology and temperature of areas of interest. Analysis of the temperature data of these wells indicates that the average geothermal gradient varies from 19.8 to 29.5°C/km along the southeast part of the Bengal Foredeep region and from 20.8 to 48.7°C/km along the northwest stable shelf. The author of this paper attempted to recalculate different geothermometer temperatures using the geochemical data taken from water samples of the basement aquifer of the Madhyapara hard rock mine area, and using acquired knowledge from this training programme. The author found that the predicted temperature is quite variable, ranging from 67 to 153°C, which may refer to a potential low-temperature geothermal field in the Madhyapara area. For assessment of the geothermal potential of Bangladesh, the authors recommends preliminary surface geological and geochemical studies be done, followed by geophysical investigations and drilling of shallow gradient wells to make a conceptual model of any geothermal systems before proceeding with drilling of a deep well.