Aseismic plate boundary in the Indo-Burmese wedge, northwest Sunda Arc
Vineet K Gahalaut et al., CSIR-National Geophysical Research Institute, Uppal Road, Hyderabad 500606, Andhra Pradesh, India. Posted online 4 Jan. 2013; http://dx.doi.org/10.1130/G33771.1.
Plate motion, crustal deformation, and earthquake occurrence processes in the northwest Sunda Arc, which includes the Indo-Burmese wedge (IBW) in the forearc and the Sagaing fault in the backarc, are very poorly constrained. Plate reconstruction models and geological structures in the region suggest that subduction in the IBW occurred in the geological past, but whether it is still active and how the plate motion between the India and Sunda plates is partitioned between motion in the IBW and Sagaing fault is largely unknown. Vineet K. Gahalaut and colleagues report results from a dense GPS network in the IBW that has operated since 2004. Their analysis of these measurements and the seismicity of the IBW suggest that the steeply dipping Churachandpur-Mao fault in the IBW accommodates the remaining motion between the India and Sunda plates through dextral strike-slip motion, and this motion occurs predominantly through velocity strengthening frictional behavior, i.e., aseismic slip. The aseismic motion on this plate boundary fault significantly lowers the seismic hazard due to major and great interplate earthquakes along this plate boundary.
Anthropogenic lead as a tracer of rock varnish growth: Implications for rates of formation
Michael N. Spilde et al., Institute of Meteoritics, MSC03-2050, University of New Mexico, Albuquerque, New Mexico 87131, USA. Posted online 4 Jan. 2013;
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