Fan beheading and drainage diversion as evidence of a 3200-2800 BP earthquake event in the Esmeraldas-Tumaco seismic zone : a case study for the effects of great subduction earthquakes

Auteurs :
DUMONT, J.F.
SANTANA, E.
VALDEZ, F.
TIHAY, J.P.
USSELMANN, P.
ITURRALDE, D.
NAVARETTE, E.

Description :
This paper provides evidence for a succession of geomorphic changes charcterized by the disruption of the Quaternary drainage network and the reshaping of the Cayapas-Santiago estuary. The increase of the discharge directed to the Gayapas River generated the change of the channel pattern downstream from the confluence, and the avulsion of a new estuary through the coastal plain. Acording to the dating of beach ridges the avulsion occured in the period 3200-2800 BP. This period corresponds also to a faster accretion of the beach ridge margin, interpreted as a response to a small uplift of the shore.


Type de document :
Article de périodique

Source :
Geomorphology (Amsterdam), issn : 0169-555X, 2006, vol. 74, n°. 1-4, p. 100-123, nombre de pages : 24, Collation : Illustration, Références bibliographiques : 71 ref.

Date :
2006

Editeur :
Pays édition : Pays-Bas, Amsterdam, Elsevier