Boulder, CO, USA - Topics include: continental deformation and the San Andreas fault; interior heating of Mars; correlation of 200-million-year-old rocks between Britain and America; environmental stress and the end-Permian and end-Triassic mass extinctions; rock weathering in Canada's Mackenzie River basin as a CO2 source rather than sink; how stable continents split in the absence of active volcanism; and geologic evolution of Alaska and the northern Pacific Rim. The GSA TODAY science article explores conceptual uncertainty in geoscience interpretation.
Long-term continental deformation associated with transpressive plate motion: The San Andreas fault
James A. Spotila et al., Virginia Tech, Geosciences, Blacksburg, Virginia 24061, USA. Pages 967-970.
The San Andreas fault is perhaps the world's best known strike-slip fault, yet we still do not fully understand how it accommodates plate motion via continental deformation. Surprisingly, the fault is not parallel to plate motion, and more often than not it is transpressionally oblique. This means that convergence occurs along the fault, resulting in mountain building. But how should this mountain building be distributed along and away from the fault" Spotila et al. complete the first systematic review of how transpressional deformation is distributed along the entire plate boundary. They find that deformation increases towards the fault zone, but that it is very heterogeneous along the fault. This implies that local boundary conditions, such as erodibility of rocks, variations in climate (precipitation), and local structural complexity, largely dictate the pattern of transpressional strain along the fault.
Martian hydrogeology sustained by thermally insulating gas and salt hydrates
Jeffrey S. Kargel et al., University of Arizona, Hydrology & Water Resources, Tucson, Arizona 85721, USA. Pages 975-978.
The ability of certain hydrated salts to transmit h
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