r by P. Riley and colleagues provides two tectonic models to explain recent (younger than three million years old) magmatism around Mammoth Mountain and Long Valley, California, USA. First, we suggest that magmatism associated with Mammoth Mountain, and extending north along the Mono-Inyo volcanic chain is part of a ridge-transform-ridge system, similar to known rift margins. Second, we suggest that fault patterns, block rotations, and plate motions produced a region of enhanced extension, creating space for the formation of the Long Valley Caldera. The two tectonic models are both a consequence of transtensional deformation occurring between the Sierra Nevada microplate and the North America plate, and suggest that the area may be an incipient rift margin.
The origins of Late Quaternary debris avalanche and debris flow deposits from Cofre de Perote volcano, Mexico
Rodolfo Daz-Castelln et al., Centro de Geociencias, Universidad Nacional Autnoma de Mxico (UNAM), Campus Juriquilla, 76230 Quertaro, Mxico. Posted online 16 July 2012; doi: 10.1130/GES708.1.
Cofre de Perote volcano is a compound, shield-like volcano located in the northeastern Trans-Mexican volcanic belt. Large debris avalanche and lahar deposits are associated with the evolution of Cofre. The two best preserved of these debris-avalanche and debris-flow deposits are the ~42,000-year-old Los Pescados debris flow deposit and the ~11,000- to 13,000-year-old Xico avalanche deposit, both of which display contrasting morphological and textural characteristics, source materials, origins and emplacement environments. Rodolfo Das-Castelln and colleagues used multiple analytical techniques to identify the most abundant clay, sulfate, ferric-iron, and silica minerals in the deposits, which were either related to hydrothermal alteration or chemical weathering processes. They next used cloud-free Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) remote sePage: 1 2 3 4 5 6 Related biology news :1
. Road-mapping the Asian brain2
. Beyond base pairs: Mapping the functional genome3
. Speeding up drug discovery with rapid 3-D mapping of proteins4
. 50 Years of Watershed Modeling -- Past, Present and Future5
. GSA Bulletin presents studies in Antarctica, Italy, Mexico, Algeria, Mongolia, and more6
. FirstMark Exhibiting and Presenting at the San Diego Academy of Family Physicians 55th Annual Postgraduate Symposium7
. Coral reef experts to present latest coral reef science during July symposium8
. Amarantus BioSciences to Present at the National Investment Banking Associations (NIBA)122nd Conference in New York City9
. John Theurer Cancer Center presents significant blood cancer research at 2012 ASCO Annual Meeting10
. Validity CTO to Present Natural ID Solutions for Improving Mobile Risk Management and User Experience at NFC Solutions Summit 201211
. The Brain Prize 2012 is presented May 9th