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Table 1.Source Parameters for Faults Included in the Hazard Analysis 2017 Update for the Henderson Site Slip Rste6 Maximum (mmyr)/ Probability of Rupture Length Sense of Mchar Recurrence Faukl Rupture Model Activity a km Sli Dips Intervals Data Sources Comments Chase Gulch(West and East)and Eleven Mile faults 0.07(0.5) Due to their close spatial association and their short lengths(5 5 km),we grouped the (Q64,Q65, 6.6(0.2) 35°E(0.2) 0.2(0.5) West-side Chase Gulch and Eleven Mile faults with the much longer East-side Chase Q66/2316,2317, 6.9(0.6) 5W E(0.6) WM:0.14 Widmann et al.(1998);Shaffer gulch fault. Slip rates are based on 2.5 in of vertical offset on Pinedale-age(13 to 25 2318) Linked 1.0 1.0 1 31 N 7.2(0.2)1 65°E 0.2 1980 ka deposits and 9.1 in on Bull Lake age 120 to 140 ka deposits Shaffer,1980 Our characterization and geometry is revised from Olig et al.(2013)to incorporate new data(Derouin,2014)and better address uncertainties regarding the southern extent of the fault.We include two rupture scenrios,A and B,and both extend along the Gore Range based on mapping done by the USBR using LIDAR data(L.W. Anderson,personal communication,2009;Derouin et al.,2010} Scenario A terminates near Frisco,is the some as the unsegmented model of Olig et al.(2013),and is favored based on evidence of similar amounts of late Quaternary offsets and Pinedale-age deposits offset along much of the Gore Range(Derouin,2014} Scenario B extends another 10 km to the southeast to include apparently older normal faults along the base of the Tenmile Range mapped by Kellogg et al.(2003)and Wallace et al. (2003}We did not include a scenario extending as far south as Alma as mapped by Tweto et al.(1978)and included in the USGS database and by Widmann et al.(1998) because neither Anderson or Wallace et al.(2003)found evidence for faulting this far southeast along the Blue River. Tweto et al.(1970)first identified evidence for Quaternary activity but West(1978) Tweto et al.(1970,1978);West believed that apparent displacement of Quaternary deposits along the fault was non- (1978);Widmann et al.(1998, tectonic. However,based on detailed surficial studies at two sites,Unruh et al.(1993) 2002);Unruh et al.(1993, concluded that Pinedale-age deposits were tectonically offset but Holocene deposits 0.02(0.2) 19%a);Kellogg et at.(2002); were in depositional contact with the fault.More recent detailed studies by the USBR 0.04(0.4) Wallace et al.(2003);O'Connell have confirmed repeated late Quaternary tectonic offsets and as much as 3.0 in of Frontal fault(or 6.9(0.2) 0.26(0.3) et al.(2005);Anderson(2007); offset on Pinedale-age surfaces(Derouin et al.,2010;Derouin,2014),and so we assign Gore Range Frontal 1.0 72(0.6) 35°E(0.2) 0.5(0.1) L.W.Anderson,USBR,personal a p(a)of 1.0. Our slip rates are based on the USBR surface offsets,relative and fault) Rupture Scenario A(0.7) 51 7.5(0.2) 50°E(0.6) WM:0.15 communication,2009;Derouin coseismogenic radionuclide ages(Derouin,2014;see Table 5).and converting surface 512302 N 65°E 02 et al. 2010•Derouin 2014 offsets to dip slip rates using the formula of Caake 199 . 6.9(0.2) 72(0.6) 7.5(0.2) Rupture Scenario B(03) 61 0.001(02) 6.6(02) 35'E(0.2) 0.004(0.6) "Suspect fault"(Widmann et al.,1998),not considered active in deterministic analysis Golden halt 6.9(0.6) 50"E(0.6) 0.02(02) Widmann et al.(1998,2002); of Unruh et al.(19%b} 742324 Independent 1.0 02 1 30 N/SS? 72 02 65°E 0.2 WM:0.007 Unroh et at. 1996b;URS 2001