Rock Varnish Layers In Ladakh

Rock Varnish Layers In Ladakh:

Magnetofossils, fossilised magnetic particles from magnetotactic bacteria, have been discovered in rock varnish layers in Ladakh.

• Rock varnish is a dark brown to black coating that covers stable, subaerially exposed rock surfaces in arid and semiarid regions.
• Findings:
  • The analysis of the rock varnish samples from Ladakh revealed higher concentrations of oxidized manganese (Mn4+) and carboxylic acid functionality, indicating organic signatures.
  • These findings suggest that the rock varnish in Ladakh, a potential Martian analogue site, contains enriched concentrations of magnetic minerals likely derived from biotic sources.
  • Magnetic minerals are those that preserve a record of the Earth’s magnetic field from when they formed and can be found in rocks, sediments, and soils.
  • Magnetofossils refer to fossilised remains of magnetotactic bacteria that contain magnetic minerals.
  • Magnetotactic bacteria leave fossilised magnetic particles in geological records.