AN ASSESSMENT OF THE GEOTHERMAL ... - Orkustofnun

Report 5 29 Akbar
Bangladesh are identified as high thermal anomalous zones, so for them further study is stressed. The
Sitakund area along the folded belt of southeast Bengal Foredeep region, where local warm springs
occur is another promising area for geothermal exploration. An attempt was made to calculate
different geothermometer temperatures using the geochemical data of the water samples of the
basement aquifer of the Madhyapara hard rock mine area and the acquired knowledge from this
training. Some of the data required for the standard practice in geochemical analysis of geothermal
exploration is relatively absent in the previously analysed data. The cation plot shows that most of the
waters are in partial equilibrium with a few samples indicating immature waters while the anions plot
suggests that the waters are peripheral. Different geothermometers have been used for calculating the
temperatures of the water samples. The predicted temperature found quite variable ranges from 67 to
153°C. The calculated saturation index (SI=log Q/log K) vs. temperature for all the samples showed
that there was no indication of silica scaling; but for calcite, most of the samples were in equilibrium
and a few of them were supersaturated so they might form scales.
The assessment of an area in the context of subsurface geothermal exploration requires a detailed
study of all surface exploration methods such as geological, geochemical and geophysical methods as
well as drilling data. Afterward, integrating all the available information needs to be done for a better
understanding on the subsurface geothermal condition, including the likely temperature of the
reservoir fluids, heat sources, flow pattern of reservoir fluids and geological structure of the reservoir,
the volume of the hot rocks, and the natural heat loss. A conceptual model of the geothermal system
has to be drawn which will comply with all results of the surface exploration before proceeding
further. The drilling of a deep exploration/production well in a geothermal system is considered the
most expensive part of the programme as well as the most risky part of a geothermal exploration.
ACKNOWLEDGEMENTS
I would like to thank the Government of Iceland for awarding me this Fellowship through the United
Nations University Geothermal Training Programme in order to attend this course.
I would like to express my most sincere thanks to Dr. Ingvar B. Fridleifsson (Director), Mr. Lúdvík S.
Georgsson (Deputy Director), Mr. Ingimar Gudni Haraldsson, Ms. Thórhildur Ísberg and Mr. Markús
A.G. Wilde for their continuous guidance, moral support, and enthusiastic help during my stay in
Iceland.
I wish to express my deepest gratitude to my supervisors, Ms. Helga Tulinius and Dr. Gísli
Gudmundsson, Mannvit Engineering, for their invaluable guidance, support, patience, and
encouragement which has made it possible to complete this project report successfully.
I am immensely benefitted by Prof. Stefán Arnórsson, University of Iceland for his valuable
suggestions on geochemistry. My special thanks to Heida Björk Halldórsdóttir, Mannvit Engineering,
for her assistance in drafting the report. I am thankful to all the lecturers who have been involved in
giving us all the knowledge and training to achieve our goals during the six months training
programme. I also appreciate all the help and assistance forwarded to me by my colleagues: Mr.
Vincent Kipkirui Koech and Mr. Jeremiah K. Kipngok, who are highly acknowledged.
Finally, I am grateful to DG of Geological Survey of Bangladesh, Ministry of Power, Energy and
Mineral Resources, Government of the People´s Republic of Bangladesh for allowing me to attend the
course with continued support.