摘要： The critical taper model has been widely used to evaluate the strength contrast between the wedge and the basal detachment of fold-and-thrust belts and accretionary wedges. However, determination of the strength parameters using the traditional critical taper model, which adopts the Mohr–Coulomb failure criterion, is difficult, if not impossible. In this study, we propose a modified critical taper model that incorporates the non-linear Hoek–Brown failure criterion. The parameters in the proposed critical Hoek–Brown wedge CHBW model can be directly evaluated via field investigations and laboratory tests. Meanwhile, the wedge strength is a function of the wedge thickness, which is oriented from stress non-linearity. The fold-and-thrust belt in western central Taiwan was used as an example to validate the proposed model. The determined wedge strength was 0.86 using a representative wedge thickness of 5.3km; this was close to the inferred value of 0.6 from the critical taper. Interestingly, a concave topographic relief is predicted as a result of the wedge thickness dependency of the wedge strength, even if the wedge is composed of homogeneous materials and if the strength of the detachment is uniform. This study demonstrates that the influence of wedge strength on the critical taper angle can be quantified by the spatial distribution of strength variables and by the consideration of the wedge thickness dependency of wedge strength. •Proposed critical taper model incorporating non-linear Hoek-Brown failure criterion•Wedge strength and the critical taper angle are wedge thickness dependent.•Wedge strength parameters can be measured via field and laboratory works.•Wedge strength heterogeneity can be evaluated directly without difficulty.•Predicted critical taper angle of homogeneous wedge varied with its thickness. 出版者： Amsterdam: Elsevier B.V 出版日期： 2016-12-05 出處： Tectonophysics, 2016-12, Vol.692, p.213-226 資源來源： Elsevier ScienceDirect Journals Complete 版權： 2016 The Authors 版權： Copyright Elsevier BV Dec 5, 2016 識別號： ISSN: 0040-1951 識別號： ISSN: 1879-3266 識別號： EISSN: 1879-3266 識別號： DOI: 10.1016/j.tecto.2016.04.026
