HR: 1340h
AN: T23D-1632    [Abstracts]
TI: GIS rock unit and lineament analysis distribution in Northern Chihuahua, Mexico: Cenozoic reactivation of the Mojave-Sonora-Megashear (?)
AU: * Martinez-Pina, C
EM: cmmartinez8@miners.utep.edu
AF: University of Texas at El Paso, 500 W University Ave., El Paso, TX 79968,
AU: Goodell, P
EM: goodell@geo.utep.edu
AF: University of Texas at El Paso, 500 W University Ave., El Paso, TX 79968,
AB: Regional tectonic and geohydrology research for the State of Chihuahua has led to the analysis of rock unit distribution and their relationship to major lineaments. GIS geology maps from Mexico and the United States were used to extract and create shapefiles of four types of rocks: Cenozoic rhyolites, andesites, basalts and conglomerates. In addition to the generation of these layers, maps, including gravity, were converted into raster and georeferenced to serve as ground-truth. Rhyolite distribution demonstrates two different patterns of the upper volcanic series, a vast continuous region and a smaller area in the north where this region is broken in distinctive patterns. Basalt and conglomerate units terminate or decrease in abundance at major lineaments. Characteristics of these features combine to form linear features. Ages of rocks are pre-Miocene, thus the linear, extensional features breaking them up are younger. A strong N-S component is present interpreted to be associated with the Rio Grande Rift. A provocative observation is the presence of multiple WNW trending features. The Rio Papagochic southeast trending topographic embayment is one part of the evidence. Miocene 18 ma NW trending transtensional faulting has been recognized in west Texas. This trend of faults has also influenced breakaway zones of detachment faults in the Early Miocene in northern Sonora. Layering of these newly recognized concurrences over traces of the proposed Mojave-Sonora-Megashear show a strong coincidence. Is this a reactivation?
DE: 8178 Tectonics and magmatism
SC: Tectonophysics [T]
MN: 2007 Fall Meeting