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      https://www.ias.ac.in/article/fulltext/jess/129/0219

    • Keywords

       

      Temperature; thermal conductivity; heat production; COMSOL; Monte Carlo.

    • Abstract

       

      The crustal structure along the 90 km seismic profile from Kuppam to Bommidi in the southern part of Archean Dharwar Craton and Southern Granulitic terrain is used to obtain a 2D thermal structure for the region. The temperatures are computed for known values of the radiogenic heat production, thermal conductivity and associated boundary conditions. The heterogeneous nature of the subsurface compels one to consider the controlling parameters to be a realization of a random process, as estimation of realistic values for these parameters is very difficult. Uncertainties in the model in such a situation can be analyzed by solving the governing heat conduction equation with its associated boundary conditions from a stochastic point of view. A 2D thermal model for this area is obtained using the finite element method for the heat conduction problem using the COMSOL Multiphysics software. The crustal temperatures for different layers along the 90 km profile is computed by incorporating randomness in thermal conductivity values. Using seismic velocities, the heat production in the layered earth is computed along the profile. The 2D temperature-depth profile along with upper and lower bounds is plotted and results obtained reveal that the temperature varies from 405$^{\circ}$ to 498$^{\circ}$ C at Moho depth along the profile. The errors are varying from 100$^{\circ}$ to 115$^{\circ}$ C. The Moho depth along the profile is seen to vary from 34 to 45 km. At a few locations, the 1D solution along with error bounds is plotted and the results are seen to match well with that of the 2D thermal result at that location.

      $\bf{Highlights}$

      $\bullet$ The 2D crustal thermal structure along with its errors is computed along the 90 km Kuppam–Bommidi profile is the Southern Granulite Terrane.

      $\bullet$ The crustal thermal structure for this profile is solved using the finite element method for the heat conduction problem with surface temperature as one boundary condition and mantle heat flow values as lower boundary conditions and incorporating thermal parameters such as thermal conductivity and heat production along the profile.

      $\bullet$ Variation in thermal structure for changes in thermal conductivity is calculated by incorporation randomness in thermal conductivity values.

      $\bullet$ The crustal temperature varies from 405$^{\circ}$ C to 498$^{\circ}$ C at Moho depth along the profile. The errors are varying from 100$^{\circ}$ C to 115$^{\circ}$ C. The Moho depth in the region varies from 34 to 45 km.

    • Author Affiliations

       

      HARINI GURUHAPPA1 SHINDE G N2 VIJAY KUMAR T2 RAMANA D V1 KIRTI SRIVASTAVA1

      1. CSIR-National Geophysical Research Institute, Hyderabad 500 007, India.
      2. SRTM University, Nanded, India.
    • Dates

       
  • Journal of Earth System Science | News

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