الفهرس 
CHAPTER ?: INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 241 |  |  |
| | | from | 241 | | |
Abstract
Wadi El-Tarfawy-Wadi El-Dabbah area is located at about 40Km southwest of Qusseir on the Red Sea coast. An airborne geophysical survey (magnetic and radiometric) and detailed ground gamma-ray spectrometric, magnetic surveys were carried out on grid lines at two areas (Um Sweider-I and Wadi
El-Ghawaby) to delineate the structural framework and to define the radiometric
anomalous zones in the study areas. In addition to five induced polarization (IP)
profiles were chosen to follow the radiometric anomalous zones at deeper depths
for the Wadi El-Ghawaby area.
The analysis of the radiometric data revealed that the highest radioactive
level is associated with the postgeosynclinal sediments (Hammamat sediments).
The high radioactivity values for the postgeosynclinal sediments are due to the
injection of these rock units by bostonite rocks, which are considered the most
important rock unit in the study area. The recorded highest equivalent uranium
values are 136.7ppm and 90.4ppm for Um Sweider-I and Wadi El-Ghawaby
areas respectively. Dose rate maps for Um Sweider-I and Wadi El-Ghawaby
areas revealed that, the most parts of the these areas are harmful to the
individuals and outside the safe limit of the permissible safe radiation dose rate
(1mSv/y).
Through the application of the two-dimensional power spectrum technique,
two main average magnetic interfaces for shallow and deep magnetic sources are
60m and 810m, 11m and 23m, 22m and 72m for Wadi El-Tarfawy-Wadi
El-Dabbah, Um Sweider-I and Wadi El-Ghawaby areas respectively. These
depths were used to discriminate the shallow and deep sources of magnetic
anomalies and produced the residual and regional magnetic component maps.
Also, Euler deconvolution technique was applied to the aeromagnetic and ground
magnetic data with two structural indices (SI) 0.0 and 1.0 to deduce the depths,
contacts, dyke or sill and faults.
The integration of all gamma-ray spectrometric and magnetic results
revealed that, the bostonite rocks have good responses on gamma-ray
spectrometric maps. Meanwhile, the bostonite rocks haven’t responses on all the
iii
magnetic maps and this is due to no magnetic contrasts between the bostonites
and the surrounding rocks.
The surface structural lineaments trends are outlined from the radiometric
data; however the shallow and deep structural lineaments are deduced from the
magnetic data. By correlation the all radiometric and magnetic dataset, four
significant trends were recorded as major trends (NW-SE, NE-SW, NNE-SSW
and NNW-SSE). Two of them (NW-SE and NE-SW) are frequently occurred on
the surface geology and the various radiometric and magnetic data. Therefore,
these trends are considered the most important trends in the study area from the
radiometric and magnetic point of view.
The apparent resistivity and chargeability measurements were inverted into
models for the Wadi El-Ghawaby area. The true resistivity values are varied from
10.4 to more than 885 ohm.m reflecting the variation of resistivity values both
vertically and horizontally. The integration of the resistivity and chargeability
data may indicate that there are some mineralized zones with depth ranging from
15m to more than 70m. These zones are mainly associated with the contact zones
between the bostonites and Hammamat sediments. The study recommended
exploration core drilling at selected sites to test the thickness, depth extent and
grade of mineralization.