AIRBORNE SPECTROMETRY AND MAGNC:TOMETR Y OF WADI ARABA AREA, NORTHERN EASTERN DESERT, EGYPT, IN SUPPORT OF GEOLOGICAL MAPPING AND WNERAL EXPLORATION

Abstract

Wadi Araba area is situated in the Northern Eastern Desert of Egypt. Its surface area reaches about 2800 km2 . The exposed rock units in the study area are represented by various lithologic associations ranging in age from Late Paleozoic to Quaternary.

An airborne geophysical (spectrometric and magnetic) survey for the study area was carried out by Aero-Service Division, Western Geophysical Company of America in I 984. This survey has been carried out along traverse flight lines oriented in a NE-SW direction at a I .5 km spacing, while the tie lines were flown perpendicularly in a NW-SE direction at IO km intervals.

The aim and purpose of this airborne geophysical study is to help delineate, modify and correct the regional lithology and structure as well as to define the anomalous radiometric zones of the Wadi Araba area using the aerialradiospectrometric and magnetic survey data as well as the regional geological map as the main sources of information.

The aeroradiospectrometric survey data have been statistically analysed and correlated with the compiled geological map ofthe area under study. This analysis resulted in the delineation of several new interpreted radiometric lithologic (IRL) units. Corresponding statistical characteristics have been computed and established for each IRL unit in the investigated area.

The radiometric-lithologic mapping will include the whole area under study which includes six formations in addition to the Quaternary and Mixed Group of Sediments. Their ranges of total aeroradioactivity vary from 0.30 to 7.70 Ur, individual arithmetic means change from 1.10 to 5.60 Ur, individual standard deviations oscillate between 0.2 I and 1.39 Ur, and arithmetic means of the means differ from 2.0 to 4.82 Ur.