Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thermoelastic Properties of Olivine and Wadsleyite
  [Fe_x,Mg_(1-x)]_2SiO_4: Their Relationship to the 410 km Seismic
  Discontinuity   We combine density functional theory (DFT) within the local density
approximation (LDA), the quasiharmonic approximation (QHA), and a model of
vibrational density of states (VDoS) to calculate elastic moduli and sound
velocities of alpha- and beta-[Fe_x,Mg_(1-x)]_2SiO_4 (olivine and wadsleyite),
the most abundant minerals of the Earth's upper mantle (UM) and upper
transition zone (TZ). Comparison with experimental values at room-temperature
and high pressure or ambient-pressure and high temperature show good agreement
with our first-principles findings. Using our results, we investigate the
discontinuities in elastic moduli and velocities associated with the
alpha-to-beta-[Fe_x,Mg_(1-x)]_2SiO_4 transformation at pressures and
temperatures relevant to the 410 km seismic discontinuity. We find the
compressional velocity contrast to be smaller than the shear velocity contrast,
in agreement with the preliminary reference Earth model (PREM).

23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom