fates-hypers 宿命 sediment sinks at depositional terrace in upper reach of the gaoping canyon...
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FATES-HYPERS 宿命FATES-HYPERS 宿命
Sediment sinks at depositional terrace in upper reach of the Gaoping Canyon
Cheng-Shing Chiang a, and Ho-Shing Yub
a Hsiuping Institute of Technology, Taichung, Taiwan, ROC
b Institute of Oceanography, National Taiwan University , Taipei, Taiwan, ROC
FATES-HYPERS 宿命FATES-HYPERS 宿命
Introduction The capability of canyons:
Sediment transfer Erosion Deposition sediments are trapped in terraces temporary or perennial sediment traps types of terrace morphology terrace formation and evolution
FATES-HYPERS 宿命FATES-HYPERS 宿命
Introduction
Sediments are traped within particular morphologies called terraces, with reference to fluvial environment. (Cirac et al.,2001; Gaudin et a.,2006)
FATES-HYPERS 宿命FATES-HYPERS 宿命
What do we need to know about terrace?
morphology featuressinkprocesses
In terms of source to sink
FATES-HYPERS 宿命FATES-HYPERS 宿命
Four types of terrace in Capbreton Canyon
(Gaudin et al., 2006)(Gaudin et al., 2006)
Horseshoe terraces (T1)• that is characterized by a flat, arcuate outer pattern surrounding an elongated and rounded
topographic high.
Hemispherical terraces (T2)• with a flat top and have an arcuate pattern
Rounded elongated terraces (T3)• that is located inside meander loops and with a rounded top
Flat elongated terraces (T4) that is flat and elongated parallel to the thalweg axis.
FATES-HYPERS 宿命FATES-HYPERS 宿命
Evolution of Capbreton Canyon morphology
(Gaudin et al., 2006)(Gaudin et al., 2006)
T1 : Horseshoe terraces
T3 : Rounded elongated terraces
T4 : Flat elongated terraces
FATES-HYPERS 宿命FATES-HYPERS 宿命
Point bar terrace? Slide- or slump-related terraces ?
Seismic profile 340-1
terrace
FATES-HYPERS 宿命FATES-HYPERS 宿命
Compare with the Compare with the Capbreton canyonCapbreton canyon
arcuate pattern
FATES-HYPERS 宿命FATES-HYPERS 宿命
ConclusionTerraces are well observed in the meandering segment of the canyon and mainly in inner parts of the meander bends, showing distinct depositional features of spill-over sediments to form levees.Four major types of terrace morphology have been established in the study area: Slide- or slump-related terraces, point bar terraces, horseshoe terraces (T1) and elongated terraces (T3).
FATES-HYPERS 宿命FATES-HYPERS 宿命
We reveal the temporary sink of terrace of the Gaoping Canyon under the highstand of sea level as characterized by a direct sediment source from a small mountainous river with high sediment load.