• 40Ar-39Ar age of carbonatite-alkaline magmatism in Sung valley, Meghalaya, India

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      https://www.ias.ac.in/article/fulltext/jess/110/03/0185-0190

    • Keywords

       

      40Ar-39Ar dating; carbonatite; Sung Valley; Rajmahal Traps; Kerguelen plume

    • Abstract

       

      40Ar-39Ar analyses of one alkali pyroxenite whole rock and two phlogopite separates of calcite carbonatites from the Sung Valley carbonatite-alkaline complex, which is believed to be a part of the Rajmahal-Bengal-Sylhet (RBS) flood basalt province, yielded indistinguishable plateau ages of 108.8 ± 2.0Ma, 106.4 ± 1.3Ma and 107.5 ± 1.4Ma, respectively. The weighted mean of these ages, 107.2 ± 0.8 Ma, is the time of emplacement of this complex. This implies that Sung Valley complex and probably other such complexes in the Assam-Meghalaya Plateau postdate the main flood basalt event (i.e., the eruption of tholeiites) in the RBS province by ∼10Ma.

    • Author Affiliations

       

      Jyotiranjan S Ray1 Kanchan Pande1 2

      1. Physical Research Laboratory, Navrangpura, Ahmedabad - 380 009, India
      2. Ottawa-Carleton Geoscience Centre, University of Ottawa, Ottawa, ON - K1N 6N5, Canada
    • Dates

       
  • Journal of Earth System Science | News

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