Chen, Yue-GauYue-GauChenLai, K.-Y.K.-Y.LaiLee, Y.-H.Y.-H.LeeSuppe, J.J.SuppeWEN-SHAN CHENLin, Y.-N.N.Y.-N.N.Lin王昱Hung, J.-H.J.-H.HungKuo, Y.-T.Y.-T.Kuo2018-09-102018-09-102007http://www.scopus.com/inward/record.url?eid=2-s2.0-34548556342&partnerID=MN8TOARShttp://scholars.lib.ntu.edu.tw/handle/123456789/330789Discrete scarps that are created or reactivated during large earthquakes are a locus of concentrated hazard. A number of the coseismic scarps activated in the 1999 Chi-Chi earthquake are actually fold scarps, which display several types of ground deformation characterized by localized folding and are distinct from classic fault scarps, which form by a fault cutting the surface. This paper documents and analyzes fold scarps that formed or reactivated in the 1999 Chi-Chi Taiwan earthquake. Our results show the Chi-Chi fold scarps can be generally divided into two types: (1) those associated with folding ahead of the tip of a blind thrust fault at shallow depths and (2) those associated with folding by kink band migration above fault bends at substantial depths ranging from ∼0.8 to 5 km). The previously published trishear model can be applied to model the former type, while a new curved hinge kink band migration model is provided to describe the behavior of the latter type. A key feature of fold scarps of the second type is that hinge zones are typically wide (25-100 m) relative to the displacement in a single earthquake (1-10 m), which exerts a significant control on fold scarp morphology and evolution. Because the coseismic strains of both types of fold scarps display relatively wide deformation zones (10-100 m) relative to fault scarps, wider set-back zones might be appropriate from a public policy point of view to alleviate the risk to structural damage and collapse resulting from permanent ground deformation. Copyright 2007 by the American Geophysical Union.application/pdf1504031 bytesapplication/pdf[SDGs]SDG11journal article10.1029/2006JB0043882-s2.0-34548556342WOS:000245022300003