EXPLORATION FOR URANIUM AND THORIUM MINERALIZATIONS AT 
WADI UM LASEIFA AREA, CENTRAL EASTERN DESERT, EGYPT: 
USING REMOTE SENSING TECHNIQUE 
T. M. Ramadane, S. À . El Mongy" and S. Salah El Deins, 
aNational Authority for Remote Sensing and Space Sciences, Egypt, ramadan_narss2002@yahoo.com 
bNational Center for Nuclear Safety and Radiation Control” 
KEY WORDS: Remote sensing, Uranium mineralizations, Airborne radiometric data, Eastern Desert, Granitic rocks, Radiometric 
materials, Gamma ray spectrometry 
ABSTRACT: 
This research aims at integrating airborne radiometric and remote sensing satellite data to prospect for radioactivity of the rocks at Wadi 
Um Laseifa, located in the Central Eastern Desert of Egypt. The study recorded some uranium anomalies along NNE-SSW trending 
fault zones within the granitic rocks. These occurrences are associated with alkali granites, pegmatitic and manganese veins, trachytic 
dykes (Gabal Hamrat Ghanam, Gabal El Delihmi, Gabal Nusla and Gabal Abu El Tiyur). Gamma ray spectrometer measurements for 
representative samples indicate the presence of Uupto 17.2 ppm in the trachytic dykes, 12 ppm in the pegmatites and 9 ppm in the 
manganese veins. Results demonstrate the accuracy of airborne radiometric data and the suitability of remote sensing techniques as a 
powerful tool in exploration for radioactive materials. 
1. INTRODUCTION 
The study region lies in the central part of the Eastern Desert of 
Egypt between Lat. 25° 30° and 25° 55° N and Long. 34° 00° and 
34? 40^ E. This study aims at integrating airborne radiometric and 
Landsat Thematic Mapper (TM) data for detecting radioactive 
anomalies in this area. 
Several authors used airborne geophysical data for geological 
mapping and regional exploration (Misener, et al., 1985, Reeves, 
1985 and Ramadan and Sultan, 2003). The radioactive 
mineralizations of the Egyptian Eastern Desert have been studied 
by many authors, the most recent studies are carried out by El 
Ghawaby, 1973, El Shazly, et al., 1973 & 1974), Ammar et al. 
(1991), El Rakaiby, (1995), Ammar, (1997) and Ramadan et al. 
(1999). 
The study area has been regionally mapped before by Sabet, 
(1961), Dardir, (1968), Sabet et al. (1976), Kamal et al. (1991), 
EGSMA, (1992), El Alfy, (1992) and Ramadan, et al., (1999). 
In the present work, the airborne radiometric maps for the 
investigated area were processed to show the distribution and 
intensities of uranium (U), thorium (Th) and potassium (K^) 
within the studied area. These maps were correlated with geologic 
and structural maps prepared by using Landsat TM images, to 
show the lithological and structural features. 
2. METHODOLOGY 
Spatial integration of various data sets such as geological map (1: 
100,000 scale), Landsat TM images (1: 100,000 scale) and 
airborne radiometric data is applied to show the distribution and 
intensities of uranium (U), thorium (Th) and potassium wy) 
within the studied area. Geographic Information System (GIS ) 
model has been designed and implemented based on the 
intersection of the buffering zones of each input layer. 
2.1 Remote sensing analysis 
2.1.1 Landsat TM Data: Landsat Thematic Mapper (TM) data for 
the study area was processed for geological and structural 
mapping using the ERDAS imagine 8.5 at the NARSS's Image 
Processing Lab. A single Landsat TM scene (Path 174 , Row 42, 
date 1986) covering the investigated area has been geometrically 
corrected and radiometrically balanced and digitally processed. 
Digital processing of Landsat TM image for the study area 
generated several products ranging from single band images, false 
color composite images (7, 4, 2 in RGB), principal component 
images (4, 2, | in RGB) to ratio images (bands 5/7, 5/1 and band 
4/3), (4/3, 3/1, 5/7) in R, G, B (scale 1:100,000). Landsat TM 
images (bands 7, 4, 2) and Principal component analysis of bands 
4. 3 and 2 were used for detecting the regional tectonic structures 
in the study area. Ratio images (5/7, 5/1, 4/3) and (4/3, 3/1, 5/7) 
in R, G, B were used for lithological discrimination of different 
rock types. In such images the investigated ultramafic rocks are 
indicated by green color, the granodiorites are indicated by red to 
pinky color, the younger granitic rocks are indicated by purple 
color (Fig. 2). 
2.1.2 Airborne Gamma-ray Survey: Wadi Um Laseifa area was 
included in the airborne gamma-ray spectrometric survey 
conducted by Aero-Service over a large segment of the central and 
southern Eastern Desert, Egypt, designated as area-11 (Aero- 
Service 1985). Airborne radiometric data represent measurements 
of the gamma-ray flux above the earth’s surface, caused by the 
radioactive decay of U, Th and K* with resolution of 200 m. The 
survey was flown along a set of parallel traverse flight lines 
oriented in a northeast-southwest direction, at 1 km spacing, while 
tie lines were flown northwest-southeast at 10 km intervals. The 
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