Archived report (descriptions no longer maintained)
Blacktail fault, Cottonwood section (Class A) No. 644b
Last Review Date: 2010-11-10
Compiled in cooperation with the Montana Bureau of Mines and Geology
| County(s) and State(s) |
BEAVERHEAD COUNTY, MONTANA |
| Physiographic province(s) |
NORTHERN ROCKY MOUNTAINS |
| Reliability of location |
Good Compiled at 1:100,000 scale. |
| Length (km) | This section is 27 km of a total fault length of 40 km. |
| Average strike | N50°W (for section) |
| Sense of movement | Normal |
| Dip Direction | NE |
| Historic earthquake | |
| Most recent prehistoric deformation | late Quaternary (<130 ka) |
| Slip-rate category | Less than 0.2 mm/yr |
| References |
Bartholomew, M.J., and Stickney, M.C., 1987, Late Quaternary faulting in southwestern Montana: Geological Society of America Abstracts with Programs, v. 19, p. 258-259. Bartholomew, M.J., Lewis, S.E., Russell, G.S., Stickney, M.C., Wilde, E.M., and Kish, S.A., 1999, Late Quaternary history of the Beaverhead River Canyon, southwestern Montana, in Hughes, S.S., and Thackray, G.D., eds., Guidebook to the Geology of Eastern Idaho: Idaho Museum of Natural History, p. 237-250. Bartholomew, M.J., Stickney, M.C., and Wasklewicz, T.A., 2004, Interaction between the northern Basin and Range and the Yellowstone stress fields near the Red Rock fault, southwestern Montana: Geological Society of America Abstracts with Programs, v. 36, no. 4, p. 12. Hurlow, H.A., 1995, Late Pliocene or younger paleostress directions from fractured clasts, Sixmile Creek Formation, lower Red Rock Valley, SW Montana: Geological Society of America Abstracts with Programs, v. 27, no. 4, p. 16. Muller. P.D., and Krol, M.A., 2008, Re-interpretation of the range-bounding faults of the Blacktail Mountains, SW Montana—Implications for Cenozoic tectonic history: Geological Society of America Abstracts with Programs, v. 40, no. 1, p. 52. Ostenaa, D., and Wood, C., 1990, Seismotectonic study for Clark Canyon Dam, Pick-Sloan Missouri Basin Program, Montana: U.S. Bureau of Reclamation Seismotectonic Report 90-4, 78 p., 1 pl. Pardee, J.T., 1950, Late Cenozoic block faulting in western Montana: Geological Society of America Bulletin, v. 61, p. 359-406. Pierce, K.L., and Morgan, L.A., 1990, The track of the Yellowstone hotspot—Volcanism, faulting, and uplift: U.S. Geological Survey Open-File Report 90-415, 68 p., 1 pl. Scholten, R., Keenmon, K.A., and Kupsch, W.O., 1955, Geology of the Lima region, southwestern Montana and adjacent Idaho: Geological Society of America Bulletin, v. 66, p. 345-404. Stickney, M.C., and Bartholomew, M.J., 1987, Preliminary map of late Quaternary faults in western Montana: Montana Bureau of Mines and Geology Open-File Report 186, 1 pl., scale 1:500,000. Stickney, M.C., and Bartholomew, M.J., 1987, Seismicity and late Quaternary faulting of the northern Basin and Range province, Montana and Idaho: Bulletin of the Seismological Society of America, v. 77, p. 1602-1625. Stickney, M.C., and Bartholomew, M.J., 1992 written commun., Preliminary map of late Quaternary faults in western Montana (digital data): Montana Bureau of Mines and Geology (digital version of MBMG Open-File Report 186), 1 pl., scale 1:500,000. Stickney, M.C., Bartholomew, M.J., and Wilde, E.M., 1987, Trench logs across the Red Rock, Blacktail, Lima Reservoir, Georgia Gulch, Vendome and Divide faults, Montana: Geological Society of America Abstracts with Programs, v. 19, p. 336-337. Witkind, I.J., 1975, Preliminary map showing known and suspected active faults in western Montana: U.S. Geological Survey Open-File Report 75-285, 36 p. pamphlet, 1 sheet, scale 1:500,000. |