3 papers
physics.geo-ph2026
A higher--order gradient framework for multi--scale seismic wave propagation
Rafael Abreu
Modeling frequency-dependent seismic wave propagation in porous media remains a major challenge because classical poroelastic theories generally require a large number of poorly co…
math.NA2026
From complex-step differentiation to a general reconstruction framework
Rafael Abreu, Chahana Nagesh
The complex-step method is traditionally derived from the Taylor expansion of an analytic function and is widely used as a numerical technique for derivative approximation. We pres…
physics.geo-ph2024
Understanding the Adjoint Method in Seismology: Theory and Implementation in the Time Domain
Rafael Abreu
The adjoint method is a popular method used for seismic (full-waveform) inversion today. The method is considered to give more realistic and detailed images of the interior of the…