Structure estimation of 2D listric faults using quadratic Bezier curve
for depth varying density distributions
Abstract
A contemporary and decisive optimization algorithm is developed for
inverting gravity anomalies due to listric faults. The cross-section
of listric faults are generally concave up, and the dip of the fault
plane gradually decreases with depth. Quadratic Bezier curves are
utilized to represent the curvature of the fault plane. The densities of
sediment deposition are assumed to be known and can take any functional
form of depth. By constraining the density, a global optimization
algorithm is adopted to estimate the fault structure by inverting
control point parameters of Bezier curves. The presented algorithm
is implemented in two different synthetic models having fixed and depth
varying density contrasts. The robustness of the algorithm is
authenticated by incorporating white Gaussian noise into synthetic
gravity anomalies. A detailed uncertainty appraisal is also performed to
justify the reliability of the algorithm. Finally, a real structure is
reconstructed using observed gravity anomalies, and the estimated
structure is verified with the structure obtained in previously
published literature. Furthermore, a Matlab based GUI is developed such
that any user can estimate real listric fault structure without any
computational difficulties.