Slope-to-basin variations in channel size, geometry and fill are related to variations in the degree of bypass associated with channels and the timing of channel backfill. On the slope, major feeder channels are deeply incised into thick laminated siltstones, have simple margins, and are vertically stacked due to proximity of fixed point sources. The channel fills are highly variable in character, reflecting deposition from both lower and higher-energy flows during late-stage backfilling. At the toe of slope, sandstones occur in nested, multi-story channel complexes not confined by single, master erosion surfaces. Channel bases are commonly marked by lenticular, coarse-grained lags deposited from high-energy bypassing flows. Channel fills are complex, and indicate repeated episodes of erosion, bypass, and backfilli, with thick-bedded sandstones concentrated in channel axes and thin-bedded sandstones and siltstones preferentially preserved along channel margins. In down-fan, more aggradational settings, lags are absent. Channels are smaller, less complex, and simply filled with thick-bedded amalgamated sandstones. These channels are relatively short-lived features that were rapidly plugged by high-energy flows. In distal, predominantly nonchannelized areas of the basin floor, sandstones form laterally extensive sheets that are broadly lenticular as a result of minor erosion, depositional mounding, and compensational stacking patterns.

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