Articles | Volume 15, issue 10
Nat. Hazards Earth Syst. Sci., 15, 2401–2412, 2015
Nat. Hazards Earth Syst. Sci., 15, 2401–2412, 2015

Research article 23 Oct 2015

Research article | 23 Oct 2015

A non-stationary earthquake probability assessment with the Mohr–Coulomb failure criterion

J. P. Wang and Y. Xu J. P. Wang and Y. Xu
  • Dept. Civil & Environmental Engineering, Hong Kong University of Science and Technology, Kowloon, Hong Kong

Abstract. From theory to experience, earthquake probability associated with an active fault should be gradually increasing with time since the last event. In this paper, a new non-stationary earthquake assessment motivated/derived from the Mohr–Coulomb failure criterion is introduced. Different from other non-stationary earthquake analyses, the new model can more clearly define and calculate the stress states between two characteristic earthquakes. In addition to the model development and the algorithms, this paper also presents an example calculation to help explain and validate the new model. On the condition of best-estimate model parameters, the example calculation shows a 7.6 % probability for the Meishan fault in central Taiwan to induce a major earthquake in years 2015–2025, and if the earthquake does not occur by 2025, the earthquake probability will increase to 8 % in 2025–2035, which validates the new model that can calculate non-stationary earthquake probability as it should vary with time.

Short summary
This paper introduces a new non-stationary calculation of characteristic earthquake probability, motivated and derived from the Mohr-Coulomb failure criterion. A total of six parameters are present in the model, including earthquake return period, fault-plane strength parameters, rock unit weight, focal depth, and the level of uncertainty of annual stress increment. In addition to the detailed derivations in the algorithm, a model demonstration is also presented in the paper.
Final-revised paper