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These short,discontinuous faults show various strikes and maybe attributed to local dissolution and/or migration of evaporite deposits in the area(Kirkham and Rogers, 1981;Unruh et al.,1993} On this basis,Widmann(1997b)categorized them as Class B faults(possibly non-seismogenic)and we assigned a lower probability of activity. Little is known about possible rates of activity but Kirkham and Rogers(1981) identified 2.7 in of offset of pediment gravels estimated to be pre-Bull Lake in age(< 0.005(03) Kirkham and Rogers(1981); 130 ka), Our assigned slip rates assume: (1)2.7 in of slip occurred since 300 ka Unnamed faults 63(0.2) W NW(0.2) 0.01((L4) Unruh et al.(1993);Widmann et (preferred rate);(2)2.7 in of slip occurred since 130 ks(maximum rate);and(3)2.7 in near Burns 6.6(0.6) 70"NW(0.6) 0.02(03) al.(1998,2002);Widmann of slip occurred since 5W ka(minimum rate).Due to their complex geometry,we 45/2296 Independent 1.0 0.4 1 13 N 6.9(0.2) 90° 0.2 WM:0.01 1997b assumed steeper dips. Unnamed faults in 0.001(0.2) Granby basin 6.0(0.2) 0.004(0.6) Widmann et al.(2002);Unruh et Not included as a Quaternary fault in Widmann et al.(1998),however,Unruh et al. (From Plate 2 of 63(0.6) 70"SW(0.5) 0.02(0.2) al.(1"2);Unruh et al.(1996a) (1992)found evidence for early to middle Pleistocene or older movement.We assumed Unruh et al. 1996s Zone 1.0 0.2 7 N/SS 6.6(0.2) 90" 0.5 WM:0.007 steeper dips for these intrabasin faults. We grouped these very short discontinuous intrabasin faults together.Geomorphic evidence for Quaternary activity is poor for 2305 and 2306(McCalpin et al.,2012b) and a scarp associated with 2307 may be fluvial(R.Kirkham,Geologic Solutions, Unnamed faults pers.comm.,2015}Additionally,rupture of this zone of faults in the Upper Arkansas near Leadville 70°N(02) 0.01(02) Valley graben may actually be associated with rupture of one of the adjacent rift (Q53,Q54, 6.3(0.2) 90°(0.6) 0.03(0.6) bounding structures(Mosquito,Sawatch or Northeastern Boundary faults),hence the Q5512305,2306, 6.6(0.6) 70°S(02) 0.17(02) lower probability of independent seismogenic activity.Due to a lack of data,we 230 Zone 1.0 0.5 14 N 6.9(0.2) WM:0.05 Widmann et al. 1998 assumed slip rates similar to the Mosquito fault. Zone- Rupture Scenario A(0.7) Includes Skylark fault of Unruh et al.(1996a). "late Pleistocene"but considered (four faults) sympathetic to Q50 and not an independent source by Unruh et al.(19%a).See text Rupture Scenario B for discussion of rupture scenarios and weights. Rupture scenarios are after mapping (025) and analysis by Olig et al.(2013). Lower P(a)assumed because faults may be (five faults) 0.01(0.2) Unruh et al.(1996a);URS nonseismogenic space-accommodation structures in the hanging wall of the WFMF. Unnamed faults in Rupture Scenario C 6.4(0.2) 0.03(0.6) (2001);Kirkham,(2004);Olig Based on the lack of post-Bull Lake age offsets(Kirkham,2004),slip rates assumed Williams Fork (0.05) 6.7(0.6) 70°W(0.5) 0.17(02) and Kirkham(2012);Olig et al. similar to the Mosquito fault(URS,2001}We assume steeper dips for this complex Valley 49/2300 six faults 0.7 1 18(floating) N 7.0(0.2) 80"W 0.5 WM:0.05 2013 zone of intrabasin faults. This high angle fault bounds the west side of the Rampart Range dipping to the southwest at the northern end and to the northeast at the southern end(Epis et al., 1976}Although scarps on alluvium suggest Quaternary activity,(Scott and Wobus, 1973),little is known about rates of activity.Apparently the Slocum Alluvium is not 7.0(0.2) offset,suggesting activity is>130ka(Kirkham and Rogers,1981).Based on suggestive 73(0.6) 70"NE(03) 0.002(0.5) Kirkham and Rogers(1981; evidence for two Quaternary events,(Kirkham and Rogers,1981�we assumed 5 to 6 Ute Pass fault zone 7.6(0.2) 90(0.4) 0.02(0.5) Unruh et al.(1994);Widmann et in of slip occurred since 300 ka for maximum rate of 0.02 mm/yr and 3 in of slip 771232 Independent 1.0 71 N/R7 70°SW 03 WM:0.01 al. 1998;2002 occurred since 1.6 Ma for our minimum rate of 0.002 mm r. Overall rate: Rupture Models-RM I 0.61(&1) (03),RM II(03),and 0.15(025) RM 111(0^ See Table 0.041(03) "Post-glacial(<15 ka)"and one of the more active faults in Colorado(Widmann et al., 2 for various weights 0.011(025) 1998} Rupture scenarios and models based on mapping by Olig and Kirkham(2012) assigned to each rupture 0.0005(0.1) and trenching by Olig et al.(2013}To better address uncertainties in fault behavior, scenario for each rupture WM:0.11 three rupture models were included here:RM I,RM II,and RM III.RMII is the model. (see Table 2 for preferred model and is similar to Olig et al.(2013�but here the weights on rupture 6.5(0.2) 35"NE(02) resulting moment Unruh et al.(1996a);Kirkham scenarios indicate the frequency or rate of the rupture occurring and ruptures are Williams Fork Rupture Scenario A 1.0 6.8(0.6) 500NE(0.6) -balanced rates (2004);Kellogg et al.(2011); moment balanced to total fault slip rates. The weights assigned to each scenario in Mountains fault (northern section only) 25 N 7.1(0.2) 65°NE(02) for each fault Olig and Kirkham(2012);Olig each rupture model and the resulting moment-balanced slip rates for each section are 50/2301 section et al. 2013 shown in Table 2.Overall or total fault slip rates are after Olig et at. 2013 6.7(0.2) Rupture Scenario B 7.0(0.6) (northern+middle 32 73(02) sections Rupture Scenario B 6.7(0.2) (northern+middle+ 7.0(0.6) southern sections) 37 7.3(0.2)