Gurmeet Singh posted an Question
November 01, 2020 • 19:24 pm 30 points
  • IIT JAM
  • Geology (GG)

Sir is d the right ans?.

Aplastic asthenosphere exists under a rigid lithosphere and above a rigid mantle because (A) The rigidity of the lithosphere is constant (B) The rigidity of the mantle is not constant (C) The tempesature above the asthenosphere is more and the pressure below is less (D) The minerals at the asthenosphere are at their melting points

1 Answer(s) Answer Now
  • 1 Likes
  • 1 Comments
  • 0 Shares
  • comment-profile-img>
    Rahul kumar Best Answer

    The correct answer should be B. Rigidity of Mantle is not constant and varies significantly with depth. The upper part of Mantle (asthenosphere) behaves like a plastic material (less rigid) and with increasing depth the rigidity increases. The minerals at the asthenosphere are not at their melting point. Mantle melting always occurs as a result of depressurization, radioactive heat or volatile influx.

    eduncle-logo-app

    one more thing sir, some times there is written deep earthquake occur at depth of 700km. is it possible?

    eduncle-logo-app

    Yes, deep earthquakes are associated with Benioff zone (convergent plate margin). Earthquakes in Benioff zone is deep; in order of 700km.

    eduncle-logo-app

    means it occus mantle in region, as lithospheric plates are 100-150 km

    eduncle-logo-app

    Yes 👍

whatsapp-btn

Do You Want Better RANK in Your Exam?

Start Your Preparations with Eduncle’s FREE Study Material

  • Updated Syllabus, Paper Pattern & Full Exam Details
  • Sample Theory of Most Important Topic
  • Model Test Paper with Detailed Solutions
  • Last 5 Years Question Papers & Answers