Forty years of paleostress analysis: has it attained maturity?

摘要

Powerful methods of paleostress analysis from fault-slip data have been used since the 1970's, and have demonstrated their capacity for reconstructing stress fields with tectonic significance. However, in some cases, these methods have been applied to samples that do not fulfill basic requirements, or developed on the basis of unsound conceptual models. Most methods of fault-slip are based on the Wallace-Bott principle (dynamic paradigm), while others invoke the necessity of remaining within the alternative kinematic paradigm, therefore inferring only finite strain or strain rate axes. The scientific community shares neither standard procedures for applying these methods, nor standard parameters for assessing the quality of results. This indicates that paleostress analysis has not attained maturity. It is necessary to see back to the conceptual and methological bases, following accurate procedures of data collection, using additional field observations, and critically assessing the results within the tectonic setting. Spatial and temporal heterogeneity of stress fields over all scales makes the mean stress tensor obtained from site analysis just an abstract notion, though indispensable for understanding lithosphere dynamics.