Determining fractal parameter and depth of magnetic sources for ardabil geothermal area using aeromagnetic data by de-fractal approach | ||
| Journal of Mining and Environment | ||
| مقاله 8، دوره 8، شماره 1، فروردین 2017، صفحه 93-101 اصل مقاله (958.24 K) | ||
| نوع مقاله: Case Study | ||
| شناسه دیجیتال (DOI): 10.22044/jme.2015.481 | ||
| نویسندگان | ||
| A. Khojamli* 1؛ F. Doulati Ardejani2؛ A. Moradzadeh2؛ A. Nejati Kalateh1؛ A. Roshandel Kahoo1؛ S. Porkhial3 | ||
| 1School of Mining, Petroleum & Geophysics Engineering, Shahrood University of Technology, Shahrood, Iran | ||
| 2School of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran | ||
| 3Department of geothermal energy, Renewable Energy Organization of Iran, Ministry of Energy, Tehran, Iran | ||
| چکیده | ||
| The Ardabil geothermal area is located in the northwest of Iran, which hosts several hot springs. It is situated mostly around the Sabalan Mountain. The Sabalan geothermal area is now under investigation for the geothermal electric power generation. It is characterized by its high thermal gradient and high heat flow. In this study, our aim is to determine the fractal parameter and top and bottom depths of the magnetic sources. A modified spectral analysis technique named “de-fractal spectral depth method” is developed and used to estimate the top and bottom depths of the magnetized layer. A mathematical relationship is used between the observed power spectrum (due to fractal magnetization) and an equivalent random magnetization power spectrum. The de-fractal approach removes the effect of fractal magnetization from the observed power spectrum, and estimates the parameters of the depth to top and depth to bottom of the magnetized layer using the iterative forward modelling of the power spectrum. This approach is applied to the aeromagnetic data of the Ardebil province. The results obtained indicated variable magnetic bottom depths ranging from 10.4 km in the northwest of Sabalan to about 21.1 km in the north of the studied area. In addition, the fractal parameter was found to vary from 3.7 to 4.5 within the studied area. | ||
| کلیدواژهها | ||
| Fractal Parameter؛ Aeromagnetic Data؛ Geothermal Field؛ Magnetic Field Sources؛ Power Spectrum؛ Sabalan | ||
| مراجع | ||
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