Staff directory
Damien Delvaux de Fenffe
Earth Sciences
Geodynamics and mineral resources
Geodynamics and mineral resources
Publication details
Delvaux, D. & Sperner, B. 2003. ‘Stress tensor inversion from fault kinematic indicators and focal mechanism data: the TENSOR program’. In: D. Nieuwland (ed), New Insights into Structural Interpretation and Modelling. Series ‘Special Publications’, 212. Geological Society, London, pp. 75-100. (PR)
Chapter in an edited book / Article in an edited book
Analysis of tectonic stress from the inversion of fault kinematic and earthquake focal
mechanism data is routinely done using a wide variety of direct inversion, iterative and grid
search methods. This paper discusses important aspects and new developments of the stress
inversion methodology as the critical evaluation and interpretation of the results. The problems
of data selection and separation into subsets, choice of optimization function, and the use of
non-fault structural elements in stress inversion (tension, shear and compression fractures) are
examined. The classical Right Dihedron method is developed in order to estimate the stress
ratio R, widen its applicability to compression and tension fractures, and provide a compatibility
test for data selection and separation. A new Rotational Optimization procedure for interactive
kinematic data separation of fault-slip and focal mechanism data and progressive stress tensor
optimization is presented. The quality assessment procedure defined for the World Stress Map
project is extended in order to take into account the diversity of orientations of structural data
used in the inversion. The range of stress regimes is expressed by a stress regime index R',
useful for regional comparisons and mapping, All these aspects have been implemented in a
computer program TENSOR, which is introduced briefly. The procedures for determination of
stress tensor using these new aspects are described using natural sets of fault-slip and focal
mechanism data from the Baikal Rift Zone.