Geologic maps of a part of the Las Vegas Basin and of the foothills of the Sangre de Cristo Mountains, San Miguel and Mora Counties, New Mexico

10.3133/om54 ◽  
1946 ◽  
Keyword(s):  
New Mexico ◽  
Las Vegas ◽  
Geologic Maps ◽  
Sangre De Cristo

AEROMAGNETIC AND GRAVITY STUDIES OF THE PRECAMBRIAN IN NORTHEASTERN NEW MEXICO

Geophysics ◽  
1962 ◽  
Vol 27 (3) ◽  
pp. 343-358 ◽  
Author(s):  
G. E. Andreasen ◽  
M. F. Kane ◽  
Isidore Zietz
Keyword(s):  
New Mexico ◽  
Las Vegas ◽  
Gravity Anomalies ◽  
Drill Hole ◽  
Survey Area ◽  
Contour Map ◽  
Precambrian Rocks ◽  
Depth Control ◽  
Sangre De Cristo ◽  
Regional Gravity

A contour map of the Precambrian surface for a part of northeastern New Mexico has been prepared from aeromagnetic, gravity, and drill-hole data. The area extends approximately from the Colorado border south to latitude 34° N., and from the foothills of the Sangre de Cristo Mountains east to longitude 104° W. Thirty-seven depths to Precambrian rocks were computed from aeromagnetic anomalies. Regional gravity anomalies were generally not suitable for quantitative analysis, but the gravity highs correlated with known areas of basement highs, providing a basis for contouring in areas of meager depth control. Drill-hole data provided 61 depths to basement in and near the survey area. The contouring along the east edge of the Sangre de Cristo Mountains was guided by exposures of Precambrian rocks. A principal feature of the contour map is the Sierre Grande Arch, a basement highland that trends southwest across the area to the northwest part of Guadalupe County. Major depressions are outlined west of Vegas Junction, northeast of Santa Rosa, and north and northeast of Las Vegas. The largest of these, the Las Vegas basin, occupies more than 1,000 square miles and may be more than 10,000 ft deep

Earthquake Hazard Estimation in Areas of Low Historical Seismicity: A Focus on the Northern Rio Grande Rift, Colorado and New Mexico

1990 ◽  
Vol 6 (4) ◽  
pp. 657-680 ◽  
Author(s):  
Charles E. Glass
Keyword(s):  
New Mexico ◽  
Gaussian Model ◽  
Rio Grande ◽  
Earthquake Hazard ◽  
Weibull Model ◽  
Historical Seismicity ◽  
Rio Grande Rift ◽  
Earthquake Activity ◽  
Sangre De Cristo ◽  
Northern Rio Grande

Estimates of the probability of future earthquake activity are difficult to make in areas where historical seismicity may be low or absent, but where young fault scarps attest to recent or ongoing tectonism. Three non-Poisson models, a Weibull model, a Gaussian model and a lognormal model, are used to estimate the earthquake hazard for one such area, the northern Rio Grande Rift. This portion of the Rio Grande Rift displays numerous Holocene faults attesting to ongoing tectonism, but displays essentially no historical seismicity. The earthquake hazard for the Sangre de Cristo fault zone from Taos, New Mexico to Salida, Colorado calculated using these models is remarkably consistent (probability of at least one Mo = 7 earthquake in the next 50 years ∼ 2.5 × 10−3), with increased hazard for the Sangre de Cristo fault in north San Luis Valley (∼5.0×10−3) and near Taos (∼1.0×10−2) due to the long holding times along these segments.

Sign in / Sign up

Export Citation Format

Share Document