Acta Geophysica vol. 59, no. 3, Jun. 2011, pp. 633-656 DOI: 10.2478/s11600-011-0006-4 © 2011 Institute of Geophysics, Polish Academy of Sciences Gravity and Magnetotelluric Investigations to Elicit the Origin of Hammam Faraun Hot Spring, Sinai Peninsula, Egypt Mohamed ABDELZAHER 1,2 , Jun NISHIJIMA 1 , Gad EL-QADY 2 , Essam ABOUD 2 , Osama MASOUD 2 , Mamdoh SOLIMAN 2 , and Sachio EHARA 1 1 Geothermic Laboratory, Earth Resource Engineering Department, Kyushu University, Fukuoka, Japan, e-mails: moh_zaher@yahoo.com (corresponding author), nishijima@mine.kyushu-u.ac.jp, ehara@mine.kyushu-u.ac.jp 2 National Research Institute of Astronomy and Geophysics, Cairo, Egypt e-mails: gadosan@yahoo.com, eaboud@yahoo.com, usaad2007@yahoo.com, amsoliman2001@hotmail.com Abstract There is a clear correlation between the principal areas of current geothermal development and the seismically active boundaries of the moving segments of lithosphere defined by the plate tectonic models of the Earth. The tectonic position of Egypt in the northeastern corner of African continent suggests that the most important areas for geothermal exploration are in the region where a cluster of hot springs with varied temperatures was located around the Gulf of Suez. Gravity and magnetotelluric surveys were made in the area of Hammam Faraun hot spring, which represents the most promising area for geothermal development in Egypt. These surveys were carried out for the purpose of eliciting the origin of Hammam Faraun hot spring. The results of the analyses and interpretations of these data show that the heat source of the hot spring is due to uplift of hot basement rock. This uplift may cause deep circulation and heating of the underground water. Key words: geothermal resources, magnetotelluric survey, geothermal development, Gulf of Suez, Hammam Faraun hot spring.