During the recessive stage of the Genesis Flood, differential vertical tectonics exposed the mountains and continents. Initially, Floodwaters flowed off the continents in sheets, but the sheets narrowed to channels, and more land was exposed. The rushing waters strongly eroded the continents and left their signature on the surface. These processes can be seen in southwest Montana, an area composed of mountain ranges and adjacent "flat-bottomed" valleys. As the western Rockies first rose, sheets of water flowing over them deposited large breccia fans in southwest Montana, east of the Beartooth Mountains, and east of the Bighorn Mountains in north-central Wyoming. Continuing uplift and erosion destroyed most of these fans. Mountaintops were exposed to varying levels of erosion during uplift. Up to several thousand meters of sediment was washed down into adjacent valleys and basins or transported out of the area. The energy of these events is seen in the erosion and transport of coarse quartzite gravel across the region. When the Floodwater became more channelized, strong down-valley currents eroded approximately 1,000 meters of the recently deposited valley fill, moving it toward the oceans.