預計會有一些地震沿科羅拉多州和新墨西哥州的里奧格蘭德裂谷發生：新研究說

預計會有一些地震沿科羅拉多州和新墨西哥州的里奧格蘭德裂谷發生：新研究說
Some earthquakes expected along Rio Grande Rift in Colorado and New Mexico, new study says
January 12, 2012
Translation by Autumnson Blog

(PhysOrg.com) -- The Rio Grande Rift, a thinning and stretching of Earth’s surface that extends from Colorado’s central Rocky Mountains to Mexico, is not dead but geologically alive and active, according to a new study involving scientists from the University of Colorado Boulder’s Cooperative Institute for Research in Environmental Sciences.
（PhysOrg.com） - 里奧格蘭德裂谷 - 一瘦長伸展的地球表面從科羅拉多州中部的落基山脈延伸到墨西哥 - 仍未死但卻是地質上地活著和活躍，根據一項涉及來自美國科羅拉多大學的博爾德分校研究環境科學合作研究所的科學家的新研究。
“We don’t expect to see a lot of earthquakes, or big ones, but we will have some earthquakes,” said CU-Boulder geological sciences Professor Anne Sheehan, also a fellow at CIRES. The study also involved collaborators from the University of New Mexico, New Mexico Tech, Utah State University and the Boulder-headquartered UNAVCO. The Rio Grande Rift follows the path of the Rio Grande River from central Colorado roughly to El Paso before turning southeast toward the Gulf of Mexico.
“我們並不預計看到很多或大型的地震，但我們會有一些地震。”科羅拉多大學博爾德分校的地質科學教授，亦是在CIRES的研究員安妮希恩說。這項研究還涉及合作者，來自新墨西哥大學、新墨西哥科技、猶他州州立大學和總部設在博爾德的 UNAVCO。里奧格蘭德裂谷跟隨格蘭德河的路徑，在轉向墨西哥灣東南部之前從科羅拉多州中部大致往埃爾帕索。
Sheehan was not too surprised when a 5.3 magnitude earthquake struck about 9 miles west of Trinidad, Colo., in the vicinity of the Rio Grande Rift on Aug. 23, 2011. The quake was the largest in Colorado since 1967 and was felt from Fort Collins to Garden City, Kan.

Along the rift, spreading motion in the crust has led to the rise of magma -- the molten rock material under Earth’s crust -- to the surface, creating long, fault-bounded basins that are susceptible to earthquakes, said Sheehan, a study co-author and also associate director of the CIRES Solid Earth Sciences Division. The team studied the Rio Grande Rift region to assess the potential earthquake hazards.

Using Global Positioning System instruments at 25 sites in Colorado and New Mexico, the team tracked the rift’s miniscule movements from 2006 to 2011. “Questions we wanted to answer are whether the Rio Grande Rift is alive or dead, how is it deforming and whether it is opening or not,” said Sheehan.

The high-precision instrumentation has provided unprecedented data about the volcanic activity in the region. Previously, geologists had estimated the rift had spread apart by up to 2 inches or 5 millimeters each year, although the errors introduced by the scientific instruments were known to be significant. “The GPS used in this study has reduced the uncertainty dramatically,” Sheehan said.

http://www.physorg.com/news/2012-01-earthquakes-rio-grande-rift-colorado.html