UTILIZATION OF HORIZONTAL–LOOP ELECTROMAGNETIC METHOD TO CONFIRM THE EXISTENCE OF AN OLD BERYL MINE WITH FOCUSING ON THE RADIOACTIVITY IN SIKEIT AREA, SOUTHEASTERN DESERT, EGYPT

Nugrus-Sikeit area was extensively mined by the ancient Egyptians, where, beryllium (Be) mineralization is associated with the mica rock along its contact with the quartzofeldspathic gneiss. Beryl and associated emerald occur in the mica rock and the quartz stringers that traverse them. The study area was considered as a limited area located in Wadi Sikeit, bounded by Long. 34o 47` 46`` & 34o 47` 51``E and Lat. 24o 37` 52`` & 24o 37` 55``N. It is covered by schist, gneiss and some granitic rocks.
The present study deals with the exploration of one of the ancient old mines in the Sikeit area using the Horizontal-Loop Electromagnetic (HLEM) method, as one of the important geophysical tools to explore the subsurface conductive bodies and mines. In addition, the radioactivity of the different rocks around the old mines was studied to determine the radiometric level and the natural radiation environment of the surveyed area. The interpretation of the data shows an important bored body related to an old mine at a depth ranging from 3 to 4.5m with a dipping angle of about 20 o to the east, and a width of more than 10m. Its conductivity reaches about 27 mho/m. In addition, the radioactivity of the rocks is in the normal level (1.4-11.4 Ur), hence, the environmental conditions remain in the safe side (the mean 0.77 mSv/y) except some scattered spots of more than 1 mSv/y.