A new tectonic map of the Iranian plateau based on aeromagnetic identification of magmatic arcs and ophiolite belts

A new tectonic map of the Iranian plateau based on aeromagnetic identification of magmatic arcs and ophiolite belts

Iranian plateau is one of the most complex geodynamic settings within the Alpine belt. The PaleoThetys and NeoThetys ocean subduction is responsible for the formation several magmatic arcs and sedimentary basin zones within plateau. These zones are separated from each other by thrust faults that display the ancient suture zones and ophiolite belts. The known magmatic arcs like Urmia Dokhtar Magmatic Arc and unknown magmatic arcs, which is covered by sediments, tracked by aeromagnetic data. It is assumed igneous and ophiolite rocks have highest magnetic susceptibility values in contrast to the lowest magnetic susceptibility values in most sedimentary rocks. In this study, averaged susceptibility map is estimated by using radially averaged power spectrum method. The high averaged susceptibility values shows a number of steep and gentle lineaments in correlation with magmatic arcs and ophiolites trends. In other hand low averaged susceptibility values indicates sedimentary basins. The results shows good correlation in the regions with high average susceptibility with known occurrences of Magmatic-Ophiolite Arcs (MOA). In the other hand the regions with low averaged susceptibility is coincides with well-known sedimentary basins like Zagros, Makran, Kopeh dagh, Tabas and other less known small basins. New proposed two parallel MOAs in eastern Iran and SE part of UDMA indicate a steeply dipping ( 60º dip) subduction zone. In contrast, shallow subduction ( 20º dip) of NeoTethys in the NW part of UDMA as well as in the Sabzevar-Kavir MOA.

Iranian plateau is one of the most complex geodynamic settings within the Alpine belt. The PaleoThetys and NeoThetys ocean subduction is responsible for the formation several magmatic arcs and sedimentary basin zones within plateau. These zones are separated from each other by thrust faults that display the ancient suture zones and ophiolite belts. The known magmatic arcs like Urmia Dokhtar Magmatic Arc and unknown magmatic arcs, which is covered by sediments, tracked by aeromagnetic data. It is assumed igneous and ophiolite rocks have highest magnetic susceptibility values in contrast to the lowest magnetic susceptibility values in most sedimentary rocks. In this study, averaged susceptibility map is estimated by using radially averaged power spectrum method. The high averaged susceptibility values shows a number of steep and gentle lineaments in correlation with magmatic arcs and ophiolites trends. In other hand low averaged susceptibility values indicates sedimentary basins. The results shows good correlation in the regions with high average susceptibility with known occurrences of Magmatic-Ophiolite Arcs (MOA). In the other hand the regions with low averaged susceptibility is coincides with well-known sedimentary basins like Zagros, Makran, Kopeh dagh, Tabas and other less known small basins. New proposed two parallel MOAs in eastern Iran and SE part of UDMA indicate a steeply dipping ( 60º dip) subduction zone. In contrast, shallow subduction ( 20º dip) of NeoTethys in the NW part of UDMA as well as in the Sabzevar-Kavir MOA.