HR: 0800h
AN: T41A-07    [Abstracts]
TI: The Cuenca de Oro, a Pull-Apart Basin Hosting Precious Metal Deposits Along the Re- Activated Seri-Tahue Terrane Boundary
AU: * Feinstein, M N
EM: mnfeinstein@utep.edu
AF: University of Texas at El Paso, Geological Sciences 500 W. University, El Paso, TX 79968, United States
AU: Goodell, P C
EM: goodell@geo.utep.edu
AF: University of Texas at El Paso, Geological Sciences 500 W. University, El Paso, TX 79968, United States
AB: At the intersection of Chihuahua, Sonora, and Sinaloa a boundary between the Seri and Tahue terranes has been hypothesized, and further refined as the Sinforosa Lineament. Near the western termination of the Sinforosa Lineament lies a topographic basin. Part of this study will be to better define this pull-apart basin, informally named the Cuenca de Oro due to its numerous precious metal deposits. The intention of this study is to test that the Seri-Tahue terrane boundary was re-energized during the beginning of extension related to the opening of the Sea of Cortez (~30ma). It is probable that the precious metal occurrences are related to the initiation of extension(alunite at El Sauzal has been dated at ~30ma). Five field excursions totaling sixty days of field work have been completed and a first draft of a regional geologic map has been made. Large shear zones support the hypothesis of a pull-apart basin. A study of the alteration and lineament intersections determine the location of many known precious metal deposits. By creating multiple cross-sections the basin can be modeled in three dimensions and a tectonic history can be interpreted. This study will present a structural analysis of the Cuenca de Oro and develop a tectonic history related temporally with the epithermal mineralization events.
DE: 3665 Mineral occurrences and deposits
DE: 8020 Mechanics, theory, and modeling
DE: 8045 Role of fluids
DE: 9350 North America
DE: 9604 Cenozoic
SC: Tectonophysics [T]
MN: 2007 Joint Assembly