• LilDumpy@lemmy.world
    link
    fedilink
    English
    arrow-up
    11
    ·
    28 days ago

    Lithosphere:

    A lithosphere (from Ancient Greek λίθος (líthos) ‘rocky’ and σφαίρα (sphaíra) ‘sphere’) is the rigid, outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust and the lithospheric mantle, the topmost portion of the upper mantle that behaves elastically on time scales of up to thousands of years or more.

    • LilDumpy@lemmy.world
      link
      fedilink
      English
      arrow-up
      10
      ·
      28 days ago

      Magnetic Anomaly

      In geophysics, a magnetic anomaly is a local variation in the Earth’s magnetic field resulting from variations in the chemistry or magnetism of the rocks. Mapping of variation over an area is valuable in detecting structures obscured by overlying material.

      • LilDumpy@lemmy.world
        link
        fedilink
        English
        arrow-up
        12
        ·
        28 days ago

        Proterozoic Eon

        Proterozoic rocks have been identified on all the continents and often constitute important sources of metallic ores, notably of iron, gold, copper, uranium, and nickel.

        • LilDumpy@lemmy.world
          link
          fedilink
          English
          arrow-up
          11
          ·
          28 days ago

          Weakened geomagnetic field:

          Over the last 200 years, the magnetic field has lost around 9% of its strength on a global average. A large region of reduced magnetic intensity has developed between Africa and South America and is known as the South Atlantic Anomaly.