• Fulltext

       

        Click here to view fulltext PDF


      Permanent link:
      https://www.ias.ac.in/article/fulltext/jess/129/0076

    • Keywords

       

      Ferricrete; Deccan high level laterites; mineral magnetism; ore microscopy; XRD; India

    • Abstract

       

      Studies based on sampling a $\sim 40 \rm{m}$ thick profile comprising the basalt protolith, saprolitic horizon and various levels of ferricretization in the Deccan upland lateritic sequence of the western Maharashtra (India), indicated episodic nature of lateritization. Mineral magnetism precisely demarcated the ferrimagnetic to anti-ferromagnetic (fm/afm) boundary at the base followed by various stages of lateritic developments in the upper horizons. The fm/afm boundary can be traced in field using magnetic susceptibility and therefore provide a datum for laterite base-level mapping. Ore microscopy details the inter-association and paragenesis of amorphous and crystalline varieties of iron oxide minerals (hematite, limonite, goethite) that are further modified by allochthonous inputs and changes in porosity. The lowermost horizons show silcretization, while the XRD studies record sporadic kaolinitic occurrence throughout the profile with gibbsite appearing in the upper part of the profile. Combination of mineral magnetic and ore microscopic observations depict frequent lateral inputs possibly during periods of heavy precipitation arresting and further reclaiming the process of lateritization to produce large composite thicknesses of the Deccan lateritic sequence without matured lateritization.

    • Author Affiliations

       

      JYOTIBALA SINGH1 S J SANGODE1 M F BAGWAN1 D C MESHRAM1 ANUP DHOBALE2

      1. Department of Geology, Savitribai Phule Pune University, Pune, India.
      2. Department of Geology, R. T. M. Nagpur University, Nagpur, India.
    • Dates

       
  • Journal of Earth System Science | News

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

© 2021-2022 Indian Academy of Sciences, Bengaluru.