Application of geophysical techniques to the interpretation of aeromagnetic survey data, South Eastern Desert, Egypt

Abstract EN

The regional-structural framework of an area (Gabal Urn Samiuki) located in the South Eastern Desert of Egypt, was delineated through the integration of six modern geophysical techiques from the informations and interpretations of aeromagnetic survey data reduced to the north magnetic pole (R I P).

Two main average interfaces at depth 0.8 and 2.0 kms below the measuring level were calculated through the application of local power spectrum.

Filtering combined with the' analytical downward continuation of the RTI’ magnetic data at the assigned two interlaces was conducted.

Four maps were drawn, two at each interface : one for the regional, and the other for residual components of the magnetic field.

In addition, the magnitude of the normalized total vector (gradient) of the field intensity was calculated at the two stated interfaces and two more maps were constructed.

Moreover, variations of the phase angle were calculated, and two other maps were prepared.

Techniques of statistical analysis of trends using the overlap method were conducted for most of the resulting maps and ten frequency curves were plotted.

Results from this study suggest die existence of five major magnelic-slruetural trends namely: Gulf of Suez-Red Sea (NNW and NW).

Najd (WNW), Tethyan (E-W), Syrian arc or Qattara (ENE) and Trans-African (NE).

The meridional (N-S) and Gulf of Aqaba (NNE) trends are not represented in the study area.

The preferred major trends of the whole lineaments coincide with the mentioned five directions.

There are series of uplifted and subsided blocks (or folding in the form of anticlines and synelines) correlate well with three main trends: WNW, E-W and ENE.

The Najd and Syrian are trends are proved to be similar in many aspects and are considered as conjugate trends.

The deep-sealed tectonic zones (diabase dykes) are associated with the NW trend, into one of which lies Gabal (G.) El Kahfa ring complex.

A similar feature to G.

El Kahfa was discovered at depth within the same zone of magnetic highs.