Mapping the subsurface structures and contacts using aeromagnetic data (case study: central and northern Egypt)

نوع مقاله : مقاله پژوهشی‌

نویسندگان

1 Lecturer, Geophysics Department, Faculty of Science, Cairo University, Giza, Egypt

2 Assistant Professor, Geophysics Department, Faculty of Science, Cairo University, Giza, Egypt

چکیده

This paper represents the analysis and interpretation of the airborne magnetic data of central and northern Egypt to delineate the subsurface faults and other structures and also the tectonic framework of the area. First, the total observed magnetic field data was reduced to the north magnetic pole (RTP) and using the power spectrum, the regional and residual magnetic fields were separated using the Butterworth filter to isolate the anomalies caused by each of them. Then, the airborne magnetic data was subjected to several filters to enhance the signals from the different magnetic sources for better delineation and edge detection. Additionally, Euler deconvolution was applied to estimate the depth of the different magnetic sources.
    The final outputs show a wide variety of magnetic anomalies reflecting different magnetic sources and subsurface features. The main subsurface structures are the linear NNW-SSE parallel to the Red Sea trend and the Gulf of Suez and the NE-SW faults and lineaments surrounding the basins in the northern and western area, the deeply rooted basic intrusions, and the depo-centers (basins) in the western and central parts of the area. Moreover, the area shows several basement uplifts and consequently faulted basins of different directions and displacements.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Mapping the subsurface structures and contacts using aeromagnetic data (case study: central and northern Egypt)

نویسندگان [English]

  • Ahmed Abdelwahed 1
  • Mohamed Gamal 2
  • Ahmed Metwally 1
1 Lecturer, Geophysics Department, Faculty of Science, Cairo University, Giza, Egypt
2 Assistant Professor, Geophysics Department, Faculty of Science, Cairo University, Giza, Egypt
چکیده [English]

This paper represents the analysis and interpretation of the airborne magnetic data of central and northern Egypt to delineate the subsurface faults and other structures and also the tectonic framework of the area. First, the total observed magnetic field data was reduced to the north magnetic pole (RTP) and using the power spectrum, the regional and residual magnetic fields were separated using the Butterworth filter to isolate the anomalies caused by each of them. Then, the airborne magnetic data was subjected to several filters to enhance the signals from the different magnetic sources for better delineation and edge detection. Additionally, Euler deconvolution was applied to estimate the depth of the different magnetic sources.
    The final outputs show a wide variety of magnetic anomalies reflecting different magnetic sources and subsurface features. The main subsurface structures are the linear NNW-SSE parallel to the Red Sea trend and the Gulf of Suez and the NE-SW faults and lineaments surrounding the basins in the northern and western area, the deeply rooted basic intrusions, and the depo-centers (basins) in the western and central parts of the area. Moreover, the area shows several basement uplifts and consequently faulted basins of different directions and displacements.

کلیدواژه‌ها [English]

  • Airborne magnetic data
  • subsurface structures
  • depth to basement
  • Egypt
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