GEOL 101 Lecture Notes - Lecture 28: Suspended Load, Overbank
Document Summary
Floods and flood deposits: when heavy precipitation falls in part of a river"s drainage basin, the water may overtop the river"s banks, the water outside of the river"s normal channel wanders away and generally stops. Owing very fast- in other words, it becomes very slack- although water in the main channel is owing faster than normal: the slack water has little competence and drops its suspended load as a ood deposit. Natural levees: overbank ow results in the ooding of the oodplain, decreased ow velocity results in deposition of suspended sediment. Flood deposits and river evolution: rivers change course over time. During oods, fast water in the channel can cut through banks to form new channels. Old channels get lled in with ood deposits: the low slope part of a river near the ocean changes most over time, multiple channels and abundant sediment form a structure called a delta.
