Slow-moving landslides pose a distinct natural hazard via damage to roads and structures, and can be significant drivers of erosion. Unlike conventional landslides, which fail catastrophically in a single event, these landslides creep at rates of centimeters to meters per year and can be continually active for years to centuries. Despite their importance, there has been little work predicting where slow-moving landslides occur. In this paper, Joel S. Scheingross and colleagues examine how tectonic faulting affects the distribution of slow-moving landslides. In a case study along the San Andreas fault, California, USA, they find that slow-moving are extremely common along the "creeping" section of the fault, which does not experience large earthquakes. However, slow-moving landslides are rare along the "locked" section of the fault, where large earthquakes are common. Their results suggest that reduced rock strength near the fault promotes the development of slow-moving landslides along the creeping San Andreas fault. In the locked section of the fault, however, large earthquakes induce rapid, catastrophic landslides which preferentially remove weak material from hillslopes and limit the development of slow-moving landslides. These results represent a first step in predicting the location of slow-moving landslides and are useful for hazards analysis and infrastructure planning.
Unprecedented erosion of the upper Texas coast: Response to accelerated sea-level rise and hurricane impacts
Davin J. Wallace and John B. Anderson, Dept. of Geosciences, University of Massachusetts, Amherst, Massachusetts 01003, USA, and Dept. of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA. Posted online 29 Jan. 2013; http://dx.doi.org/10.1130/B30
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Geological Society of America