Rapidly-migrating and internally-generated knickpoints can control submarine channel evolution.
Nat Commun
; 11(1): 3129, 2020 06 19.
Article
en En
| MEDLINE
| ID: mdl-32561722
ABSTRACT
Submarine channels are the primary conduits for terrestrial sediment, organic carbon, and pollutant transport to the deep sea. Submarine channels are far more difficult to monitor than rivers, and thus less well understood. Here we present 9 years of time-lapse mapping of an active submarine channel along its full length in Bute Inlet, Canada. Past studies suggested that meander-bend migration, levee-deposition, or migration of (supercritical-flow) bedforms controls the evolution of submarine channels. We show for the first time how rapid (100-450 m/year) upstream migration of 5-to-30 m high knickpoints can control submarine channel evolution. Knickpoint migration-related changes include deep (>25 m) erosion, and lateral migration of the channel. Knickpoints in rivers are created by external factors, such as tectonics, or base-level change. However, the knickpoints in Bute Inlet appear internally generated. Similar knickpoints are found in several submarine channels worldwide, and are thus globally important for how channels operate.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Nat Commun
Asunto de la revista:
BIOLOGIA
/
CIENCIA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Reino Unido