We compare the geomorphology of several convergent continental margins to constrain the seismic hazard of the Cascadia margin offshore Oregon, and present the possibility of a slow earthquake mechanism for a characteristic Cascadia event. The Cascadia seafloor has a very delicate bathymetry, with well‐preserved landslides and noneroded slopes approaching 20°, unusual for a margin that produces M∼9 earthquakes. Three‐dimensional seismic and multibeam bathymetry data from the Nankai Trough suggest ubiquitous erosion over the entire margin with a smooth lower slope, devoid of large landslides, as would be expected on an accretionary margin that produces M∼8.5 earthquakes. The accretionary Makran (Pakistan) and Kodiak (Alaska) margins have evidence of mass wasting and smooth lower slopes that lack large landslides. The nonaccreting Nicaraguan, Sanriku, and Aleutian margins have large, well‐preserved landslides that add roughness elements to the slope, and have produced anomalously large tsunami, suggesting a slow source mechanism. Quantitative analysis of the lower slope roughness suggests the Cascadia has a characteristic geomorphology substantially different than the other sedimented convergent margins. The geomorphology, heat flow, pore pressure regime, and accounts of the 1700 “megathrust” event suggest a possible characteristic earthquake with a slow source mechanism. Rupture velocity would be high enough to be tsunamigenic, but accelerations would be low such that downslope erosion is minimal. To make the distinction between a slow and rapid source mechanism is critical in planning for seismic hazard in the Pacific Northwest.

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This Article reviews Environmental Impact Statements (EIS) completed in conjunction with Resource Management Plan (RMP) revisions conducted by the Bureau of Land Management (BLM) in Colorado, Montana, Utah, and Wyoming between 2004 and 2014. Based on our review of sixteen EISs, we found that RMP revisions increased application of more protective surface use stipulations by statistically significant amounts without causing a statistically significant change in either the number of jobs created or the pace of oil and gas development. In fact, both the number of jobs created and wells drilled increased slightly despite strengthened environmental protections. We also found that Draft RMP EISs that are completed on an accelerated timeline come with a heightened risk that supplementation will be needed. The delays associated with preparing a Supplemental EIS far outweigh the timesaving associated with fast-tracking Draft EIS preparation and provide a strong caution against rushing the NEPA process.