AIRBORNE MAGNETIC DATA INTERPRETATION OF AL-AYS SEISMICALLY ACTIVE AREA, SAUDI ARABIA

Interpretation of magnetic data for the volcanic and seismic active areas can provide valuable information required to imagine the most likely scenario of the site situation and future activity. Mapping the structural architecture allows elucidating the nature of the seismic activities and the controlling structures. Moreover, repeated magnetic measurements provide a key tool to update the state of the volcanic activity and magmatic intrusions. This study presents the analysis and interpretation of the magnetic data of Al-Ays area, western Saudi Arabia. The area has known Cenozoic volcanic eruption and recently possessed an earthquake of 5.7 magnitudes, followed by tens of thousands of small earthquakes. Magnetic data analysis enables mapping the depth and extent of the basaltic flows, the depth to the Curie isotherm (high-temperature magma) and provides baseline information for future magnetic measurements to monitor the magma intrusions. On the other hand, the interpreted near-surface and deep-seated structures shows spatial correlation of the medium earthquakes (more than 4 magnitudes) with the NNW-SSE structural trend while the minor events correlated to both the NE-SW and NNW-SSE structural trend.