ANALYSIS OF GRAVITY AND MAGNETIC DATA IN THE STUDY OF THE STRUCTURE AND TECTONICS OF THE ARAR AREA, SOUTHWESTERN DESERT, IRAQ.

The interpretation of the Bouguer gravity map and the total magnetic field data of the Arar area reveals details of the basement depth, the general structure, and the tectonic history of the area. The locality studied is demonstrated to be a zone of uplift bordered from the east by the Ma'ania depression and by less conspicuous features from other sides. The depth to the top of the elevated basement is about 5. 5 km, judged from a basic intrusion within the uplifted zone. It is demonstrated that the application of different analytical interpretation methods to the gravity data outlines many linear features related to the rejuvenation of the older tectonic elements of the Hejaz and Najd orogenic movements during the Alpine orogeny. Other trends outlined from aeromagnetic interpretation and LANDSAT data are also related to the major trends affecting the area. The interpretation of two major magnetic and gravity profiles across the area is conducted by modeling, assuming a variety of geological settings. One of these models satisfies both sets of geophysical data and has been adopted for this study.