Towards automating complex fault modeling and analysis

par Guillaume Caumon

vendredi 16 octobre à 13h00

ENSG - Room G201

Abstract:

In this seminar, I will present some ideas on a possible theoretical framework to describe complex faults in three dimensions. The goal is to exchange and discuss on a paper project started in 2013 and recently also presented at the IAMG conference.

Over the past decade, the development of implicit surfaces for representing three-dimensional geological structures has resulted in significant improvement in the automation and robustness of fault network modeling. However, complex fault networks and splay faults are not easily represented with implicit surfaces and call for specific modeling strategies. The standard practice in geomodeling is to represent faults as open discontinuity surfaces, without direct consideration for conceptual fault growth models. In this work, we review the origin and main features of various complex fault configurations encountered in nature. We propose three approaches combining structural geology and topology to describe faults:

(1)    An elementary implicit fault representation, which describes a fault by  combining a series of scalar and vector fields. This approach is appropriate  for isolated faults and branching faults, when using an intersection operator.

(2)    A piecewise explicit fault representation, which makes it possible to build faults with internal branch lines by segmenting the fault surface into several explicit charts.

(3)    A composite implicit fault representation, which combines several elementary faults into a complex one. This last approach is closer to structural geology and clears the path to a unified theoretical framework for the three-dimensional description of fault surfaces and their associated deformation.