Partial Report for Southern Sangre de Cristo fault, Hondo section (Class A) No. 2017d
Compiled in cooperation with the New Mexico Bureau of Mines and Mineral Resources
citation for this record: Kelson, K.I., Kirkham, R.M., and Machette, M.N., compilers, 1998, Fault number 2017d, Southern Sangre de Cristo fault, Hondo section, in Quaternary fault and fold database of the United States: U.S. Geological Survey website, http://earthquakes.usgs.gov/hazards/qfaults, accessed 10/01/2014 08:14 AM.
|Synopsis||General: The Southern Sangre de Cristo fault is a west-dipping fault that in New Mexico forms the border between the Sangre de Cristo Mountains and the San Luis basin, and in Colorado forms the border between San Pedro Mesa to the east and San Luis Valley to the west. At the New Mexico/Colorado border there is an embayment in the Sangre de Cristo range front that causes it to deflect eastward to the Northern Sangre de Cristo fault .|
Sections: This fault has 5 sections. The four sections in New Mexico are better exposed and have been studied in more detail than the single section in Colorado. Menges (1988 #1120; 1990 #1116; 1990 #1387) defined 4 geometric segments and 13 subsegments of the Southern Sangre de Cristo fault in New Mexico on the basis of physiographic and geomorphic expression of the fault zone and the morphology of the Sangre de Cristo range front in New Mexico, but did not investigate the part of the fault that extends north into Colorado. The trace of the fault in Colorado is mainly buried by Quaternary landslide debris.
|County(s) and State(s)||TAOS COUNTY, NEW MEXICO |
|Physiographic province(s)||SOUTHERN ROCKY MOUNTAINS |
|Reliability of location||Good|
Compiled at 1:250,000 scale.
|Geologic setting||The Southern Sangre de Cristo fault is part of a major rift-margin structure of Neogene age that borders the eastern margin of the Rio Grande rift in south-central Colorado and north-central New Mexico. The entire Sangre de Cristo fault system generally forms the boundary between the San Luis basin, a narrow (10-25 km wide), east-tilted, asymmetrical half-graben on the west, and the Sangre de Cristo Mountains on the east. There is 7-8 km of structural relief on Precambrian basement rock across the Sangre de Cristo fault zone. The western margin of the San Luis basin has comparatively little displacement, and no evidence of late Quaternary displacement. The southern end of the fault merges with or intersects the north-down, sinistral Pilar section of the Embudo fault [2007a] near the village of Talpa, New Mexico. Wong and others (1995 #1155) note that a few well-located earthquakes appear to have occurred in the vicinity of the fault in New Mexico.|
|Length (km)||This section is 21 km of a total fault length of 96 km.|
|Average strike||N32°W (for section) versus N6°W (for whole fault)|
|Sense of movement||Normal|
|Paleoseismology studies||Menges (1988 #1120; 1990 #1116; 1990 #1387) mapped the fault traces and conducted detailed morphometric analyses of the fault scarps. However, there have been no detailed paleoseismic investigations of the southern Sangre de Cristo fault.|
|Geomorphic expression||Prominent west-facing fault scarps are present on late Pleistocene and possibly Holocene alluvial fans derived from the Sangre de Cristo Mountains. Menges (1988 #1120; 1990 #1116; 1990 #1387) documents the presence of truncated ridge spurs and triangular facets along the Sangre de Cristo range front, and interprets these as products of long-term displacement.|
|Age of faulted surficial deposits||Kelson (1986 #1109) mapped late Quaternary deposits and some fault strands along this section, and shows faulted Pleistocene alluvial-fan deposits. Menges (1990 #1116; 1990 #1387) did not map surficial deposits along the fault, but concludes that this fault section has experienced middle to early Holocene movement.|
|Most recent prehistoric deformation||Latest Quaternary (<15 ka)|
|Recurrence interval||10 to 50 k.y.|
|Slip-rate category||Less than 0.2 mm/yr|
|Date and Compiler(s)||1998|
Keith I. Kelson, William Lettis & Associates, Inc.
Robert M. Kirkham, Colorado Geological Survey
Michael N. Machette, U.S. Geological Survey
|References||#1180 Chapin, C.E., and Cather, S.M., 1994, Tectonic setting of the axial basins of the northern and central Rio Grande rift, in Keller, G.R., and Cather, S.M., eds., Basins of the Rio Grande rift—Structure, stratigraphy, and tectonic setting: Geological Society of America Special Paper 291, p. 5-25.|
#1181 Dungan, M.A., Muehlberger, W.R., Leininger, L., Peterson, C., McMillan, N.J., Gunn, G., Lindstrom, M., and Haskin, L., 1984, Volcanic and sedimentary stratigraphy of the Rio Grande gorge and the late Cenozoic geologic evolution of the southern San Luis Valley, in Baldridge, W.S., Dickerson, P.W., Riecker, R.E., and Zidek, J., eds., Rio Grande rift—Northern New Mexico: New Mexico Geological Society, 35th Field Conference, October 11-13, 1984, Guidebook, p. 157-170.
#1109 Kelson, K.I., 1986, Long-term tributary adjustments to base-level lowering northern Rio Grande rift, new Mexico: Albuquerque, University of New Mexico, unpublished M.S. thesis, 210 p.
#1183 Kluth, C.F., and Schaftenaar, C.H., 1994, Depth and geometry of the northern Rio Grande rift in the San Luis Basin, south-central Colorado, in Keller, G.R., and Cather, S.M., eds., Basins of the Rio Grande rift—Structure, stratigraphy, and tectonic setting: Geological Society of America Special Paper 291, p. 27-37.
#1955 Lipman, P.W., and Mehnert, H.H., 1975, Late Cenozoic basaltic volcanism and development of the Rio Grande depression in the southern Rocky Mountains, in Curtis, B.F., ed., Cenozoic history of the southern Rocky Mountains: Geological Society of America Memoir 144, p. 119-154.
#1113 Machette, M.N., and Personius, S.F., 1984, Map of Quaternary and Pliocene faults in the eastern part of the Aztec 1° by 2° quadrangle and the western part of the Raton 1° by 2° quadrangle, northern New Mexico: U.S. Geological Survey Miscellaneous Field Studies Map MF-1465-B, 1 sheet, scale 1:250,000.
#791 McCalpin, J.P., 1982, Quaternary geology and neotectonics of the west flank of the northern Sangre de Cristo Mountains, south-central Colorado: Colorado School of Mines Quarterly, v. 77, no. 3, p. 1-97.
#1120 Menges, C.M., 1988, The tectonic geomorphology of mountain-front landforms in the northern Rio Grande rift near Taos, New Mexico: Albuquerque, University of New Mexico, unpublished Ph.D. dissertation, 339 p.
#1387 Menges, C.M., 1990, Late Quaternary fault scarps, mountain-front landforms, and Pliocene-Quaternary segmentation on the range-bounding fault zone, Sangre de Cristo Mountains, New Mexico, in Krinitzsky, E.L., and Slemmons, D.B., eds., Neotectonics in earthquake evaluation: Geological Society of America Reviews in Engineering Geology, v. 8, p. 131-156.
#1116 Menges, C.M., 1990, Late Cenozoic rift tectonics and mountain-front landforms of the Sangre de Cristo Mountains near Taos, New Mexico, in Bauer, P.W., Lucas, S.G., Mawer, C.K., and McIntosh, W.C., eds., Tectonic development of the southern Sangre de Cristo Mountains, New Mexico: New Mexico Geological Society, 41st Field Conference, September 12-15, 1990, Guidebook, p. 113-122.
#1124 Personius, S.F., and Machette, M.N., 1984, Quaternary and Pliocene faulting in the Taos Plateau region, northern New Mexico, in Baldridge, W.S., Dickerson, P.W., Riecker, R.E., and Zidek, J., eds., Rio Grande rift—Northern New Mexico: New Mexico Geological Society, 35th Field Conference, October 11-13, 1984, Guidebook, p. 83-90.
#1390 Tandon, K., 1992, Deep structure beneath the San Luis basin in Colorado from reprocessing of an industry reflection survey: Ithaca, New York, Cornell University, unpublished Ph.D. dissertation, 285 p.
#1142 Upson, J.E., 1939, Physiographic subdivisions of the San Luis Valley, southern Colorado: Journal of Geology, v. 47, p. 721-736.
#1155 Wong, I., Kelson, K., Olig, S., Kolbe, T., Hemphill-Haley, M., Bott, J., Green, R., Kanakari, H., Sawyer, J., Silva, W., Stark, C., Haraden, C., Fenton, C., Unruh, J., Gardner, J., Reneua, S., and House, L., 1995, Seismic hazards evaluation of the Los Alamos National Laboratory: Technical report to Los Alamos National Laboratory, Las Alamos, New Mexico, February 24, 1995, 3 volumes, 12 pls., 16 appen.