Developing an accessible method to generate 3D fault models

Abstract

The study of faults is a key aspect of earth science research. 3D models of fault systems have often been constructed in various geoscience studies to understand the underlying earth better. Plotting faults in seismotectonic maps helps to uncover the geological structure and dynamics of a region. Traditionally, these 3D fault models and maps are made through tedious processes or in expensive software inaccessible to many researchers. Tectoplot, a GMT-based, open-source seismotectonic plotting tool developed by Bradley (2021), has made it much easier to create seismotectonic maps, cross-sections and oblique block diagrams. In this project, we have developed a programme to easily generate accurate 3D fault models that can be plotted in tectoplot. The programme is written in MATLAB and has a Graphical User Interface (GUI) so that users can carry out essential operations without the hassle of scripts. The GUI integrates earthquake hypocentres and surface trace data with strike, dip, depth range, smoothness, and other fault parameters to generate reliable representations of fault surfaces. Besides thrust and normal faults, the programme also handles vertical strike-slip faults equally well. The accuracy of faults can be improved by refining the earthquake hypocentre dataset and iterating the interpolation of fault surfaces. The iteration process has been shown to improve the fault surface significantly. When combined with tectoplot, the programme would make it easier to visualize and understand faults and related hazards. The fault surface may also be exported as standalone models in other research.