Ground follow-up of the airborne gamma-ray spectrometric survey data, ramlet HOMAYYER area, east abu-zeneima, southwestern Sinai, Egypt

Abstract

Ramlet Homayyer area is located in the southwestern part of Sinai Peninsula, Egypt, to the east of Abu-Zeneima city, located on the eastern coast of Gulf of Suez, Red Sea. The Paleozoic succession in the study area (up to 300 m thick) overlies the basement complex and is covered by basaltic sheets. The lithologic nature of the Paleozoic rocks played a very important role in the localization of various mineralizations (e.g. Mn, Fe, Cu, REEs, Th … etc.)In the present study of Ramlet Homayyer area, ground spectral gamma-ray survey was conducted along N-S profiles, equally-spaced, with lengths of about 2.5 km, and the total area equals about 10 km2. The measurements were conducted using a portable gamma-ray spectrometer, model GS-512. The examination of the total-count (T.C.) radiometric contour map shows that the radioactivity values vary widely from 3.4 Ur to 101.3 Ur. The potassium (K) content in Ramlet Homayyer area ranges from 1.2% to 16.0%. The equivalent thorium (eTh) content in the study area has a maximum value reaching about 68.9 ppm. The equivalent uranium (eU) content attains its maximum value reaching about 84.0 ppm. Factor analysis technique, which provides a way of thinking about radiospectrometric elements and ratio interrelationships alltogether was carried out.The application of factor analysis technique, helped to delineate the zones of high concentrations of eU, eTh and K separately, where the first factor (F1) can delineate high eU zones, (F2) high eTh zones and (F3) high K zones. The radiometric lithologic mapping was conducted for the whole area, by testing the homogeneity of all measurements recorded indicates that the distribution of the radioactivity all over the area is not homogeneous. This indicates that the lithological cover of the study area cannot be considered as one lithologic unit, but contains different types of rock units. Each Interpreted radiometric lithologic units (IRLU) is corresponding to one geomorphological mass or features.As a result of the ground radiometric survey of the study area, chemical analyses for some selected samples were taken and conducted from the anomalous zones at G. Homayyer, G. Ghorabi and Khameila areas. These analyses showed presence of concentrations of uranium up to 147 ppm, 58 ppm, 52 ppm in addition to trace elements with high concentrations of some elements as: Y, Cr, W, Sr and Ag, which gives 6819,768,314,561 and15 ppm respectively.