Geological and Tectonic Setting of the Kamoreib Metavolcanics, Southern Hamisana Area, Red Sea Hills, NE Sudan
[1]
Musab A. Eljah, Faculty of Petroleum and Minerals, Al Neelain University, Khartoum, Sudan.
[2]
Esamaldeen Ali, Faculty of Petroleum and Minerals, Al Neelain University, Khartoum, Sudan.
[3]
Abdalla E. M. Elsheikh, Faculty of Petroleum and Minerals, Al Neelain University, Khartoum, Sudan.
[4]
Khalid A. Elsayed Zeinelabdein, Faculty of Petroleum and Minerals, Al Neelain University, Khartoum, Sudan.
The Kamoreib area lies in the southern part of the Hamisana Shear Zone (HSZ), within the Nubian Shield as a transitional area between Gabeit and Gabgaba terrains. The tectonic setting of this area is relatively poorly understood. Therefore, the present investigation is concerned mainly with the geological and tectonic setting of the metavolcanic group at Kamoreib area as a key to the recognition and understanding of the tectonic setting of the southern Hamisana area through petrographic and geochemical analysis. Detailed geological mapping based on interpretation of enhanced satellite image, field observation and petrographic investigations revealed that the mapped area is built up of metavolcanic assemblage ranging from basic to acid in composition. The metavolcanics include porphyritic dacite, amygdaloidal andesite, andesite, rhyolite and basalt, intercalated with tuffaceous materials. These rocks are highly sheared, hydrothermally altered and regionally metamorphosed to greenschist facies. Petrographic and geochemical analysis revealed that the metavolcanics represent a mature island arc environment, which is characterized by calc-alkaline geochemical affinity. The rocks were generated above a belt of subduction zone that is later affected by the HSZ. The geographic distribution of the metavolcanics supported by the geochemical analysis present a perspective for constraining subduction polarity of the Kamoreib volcanic arc. The outcome of the present investigation revealed that the Kamoreib volcanics were formed over a northwesterly-dipping subduction zone.
Tectonic Setting, Petrography, Geochemistry, Metavolcanics, Hamisana, Red Sea Hills, Sudan
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