6. North Branch Formation

North Branch Formation

Following the impact event, it appears there was a prolonged period of aridity across the region that last between several hundred thousand to perhaps a couple million years long. Sedimentation during this time was slower, or interspersed with periods of erosion. The depositional regime begins with some aeolian sedimentation, but changes further upsection to intermittent streams and lacustrine deposits. This makes it appear that the seasonal monsoon system had changed to bring in more seasonal moisture with the winds, which would then dry out to leave behind alternating layers of stream sediments, lacustrine deposits, and evaporites.