Feature Line Detection on Triangulated Meshes A Geological Application

Abstract

We present in this article an algorithm dedicated to the feature line detection on 3D triangulated outcrop meshes. These lines corresponding to geological elements can be extracted by geometrical properties. Our approach uses differential quantities and especially principal curvatures and their derivatives. The roots of these derivatives describe particular lines called ridge lines for convex parts and ravine lines for concave parts. Then it is possible to build a set of polylines matching with ridges and ravines. Finally we apply a directional filtering to keep geological structures oriented in a particular direction. The proposed algorithm fits in a basis of a tool devoted to assist geologists during the outcrop analysis and interpretation.