Major element geochemistry of basalt exposed at Ranikot area, lower Indus basin, Pakistan
Keywords:
Geochemistry; Basalts; Lower Indus basinAbstract
Major element geochemical studies have been carried out on samples obtained from Cretaceous/Tertiary exposed section of basalt at Ranikot, a part of Laki Range in lower Indus basin, to classify these basalts and determine their origin. The whole-rock geochemical data confirm the rock type either as the basalts or basanites. Major elements data based various discrimination diagrams were used to determine the past tectonic setting of these basalts. To know the tectonic history of basaltic flows in Ranikot area, the triangular classification diagram is also used.
These are considered as tholeiitic basalts of continental flood basalt origin. These basalts are interpreted to be the age equivalent of the famous Deccan Traps of India and hence the tectonic environments proposed for the emplacement of Deccan Traps may equally be applied to the basalts exposed in lower Indus basin of Pakistan
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