Geochemistry of siliciclastics major elements in Oman continental shelf, Chabahar: Implications for provenance, paleoclimatic conditions and tectonic setting

Document Type : مقالات پژوهشی

Authors

• Sedigheh Amjadi
• Mohammad Hossein Mahmudy Gharaie
• Reza Moussavi Harami
• Asadollah Mahboobi
• Hamid Alizadeh

10.22067/sed.facies.v6i1.8247

Abstract

For interpretation of source of sediments, paleoclimatic conditions and tectonic setting of marine sediments in Makran region, Chabahar, fifteen samples from five cores from Oman continental shelf sediments have been analyzed. Analyses of major elements revealed that the dominant source may have been from felsic and intermediate rocks. The positive correlation of Al2O3 with K2O and CaO, and abundance of Al2O3 suggest that these elements are primarily controlled by the dominant clay minerals. Based on major element geochemistry, the climatic conditions is warm and arid and Chemical Index of Alteration (CIA) and Plagioclase Index of Alteration (PIA) values of sediments show that chemical alteration may have done by leaching. However, a value of ICV is indicative of recycled sediment. The quartz–toleitic rocks are likely to be the main source for sediments, which are common in back arc zone of Makran subduction. This sediment is product of long washed recycled sediments after several uplifting stages in active Makran subduction zone.

Keywords

• Geochemistry
• sediments origin
• tectonic setting
• (CIA)
• (PIA)
• paleoclimate
• Oman Sea
• Chabahar

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