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We investigate the role of landslide dams, spatial changes in lithology, and rock uplift on faults in the formation of knickzones on bedrock rivers. We focus our analysis in the southwestern Annapurna Range of the central Nepalese Himalaya where detailed geologic maps, topographic data, field observations, and aerial photographs are available. We identified knickzones in our study area from normalized river steepness indices (ksn values) extracted from river longitudinal profiles derived from a 25 m digital elevation model we interpolated from digitized topographic map contours. We compared the location of these knickzones with (1) lithologic contacts and faults from a detailed geologic map of the Modi Khola valley and (2) inferred ancient landslide dam features mapped from field observations and aerial photographs. The steepest location on the Modi Khola occurs near the same latitude as the steepest reach on the Mardi Khola located directly to the east, potentially highlighting a major topographic transition across the Annapurna. However, we find that landslide dams once blocked the flow of the Modi Khola, and damming followed by incision after landslide breaching can explain the location of these knickzones without the need for active faulting near the Main Central thrust. We also conclude that (1) knickzones do not correlate with any spatial changes in lithology and (2) knickzones generated by rock uplift on unmapped faults cannot be ruled out. We emphasize that disentangling the processes responsible for knickzone formation remains challenging even when high‐resolution geologic and topographic data are available. Key Points Landslide dams explain river knickzones without the need for active faulting We observe no correlation between river knickzones and lithologic contacts Out‐of‐sequence thrust faulting near the MCT may not be necessary

New automation, visualization, and quantification methodologies are presented and applied to the rheology and morphology of serpentinite mud volcanoes in the Mariana Forearc. The methods can be used in submarine and subaerial settings to characterize surface features of mud or lava flows, mass-wasting deposits, slump scars, and fault scarps. Three sequential mudflows are characterized for Big Blue Seamount, for which we define surface morphology, distal edges of flows, corrected thickness, underlying slopes, flow directions, and volumes. Results indicate a significant increase (from upper to lowermost flows) in distal edge thickness (13 m, 30 m, 62 m), volume (6.4×10 7 m3, 4.0×108 m3, 6.7×109 m3), and mean yield strength (36 kPa, 80 kPa, 170 kPa). We also calculate the volumes of five mud volcanoes using bathymetric and multichannel seismic data (where available). The application of these volume calculations to estimates of the amount of source protolith (peridotite) required to form the seamounts indicates that the serpentinite must derive from a continually renewed conduit.