Fig. 3
From: Coda wave interferometry during the heating of deep geothermal reservoir rocks
Illustration of the principle of the numerical approach. Using a finite element method (Code_Aster), we apply a thermal and mechanical loading, step by step, to the numerical sample chosen to be of same size as the experimental sample (40 × 20 mm). During each step, the mechanical loading is a 0.3 MPa vertical stress and the thermal loading is a constant temperature at the borders. Temperature is increased by steps of 10 °C. The wave propagation is computed using a spectral element method (SPECFEM2D). A Ricker wavelet (see top-right insert) is emitted in the medium from the source (top) and recorded at the opposite side (bottom) by a virtual 32-sensor receiver array