Bedload-to-suspended load ratio and rapid bedrock incision from Himalayan landslide-dam lake record

Beth Pratt-Sitaula, Michelle Garde, Douglas W. Burbank, Michael Oskin, Arjun Heimsath, Emmanuel Gabet

Research output: Contribution to journalArticle

67 Citations (Scopus)

Abstract

About 5400 cal yr BP, a large landslide formed a > 400-m-tall dam in the upper Marsyandi River, central Nepal. The resulting lacustrine and deltaic deposits stretched > 7 km upstream, reaching a thickness of 120 m. 14C dating of 7 wood fragments reveals that the aggradation and subsequent incision occurred remarkably quickly (∼ 500 yr). Reconstructed volumes of lacustrine (∼ 0.16 km3) and deltaic (∼ 0.09 km3) deposits indicate a bedload-to-suspended load ratio of 1:2, considerably higher than the ≤ 1:10 that is commonly assumed. At the downstream end of the landslide dam, the river incised a new channel through ≥ 70 m of Greater Himalayan gneiss, requiring a minimum bedrock incision rate of 13 mm/yr over last 5400 yr. The majority of incision presumably occurred over a fraction of this time, suggesting much higher rates. The high bedload ratio from such an energetic mountain river is a particularly significant addition to our knowledge of sediment flux in orogenic environments.

Original languageEnglish (US)
Pages (from-to)111-120
Number of pages10
JournalQuaternary Research
Volume68
Issue number1
DOIs
StatePublished - Jul 2007
Externally publishedYes

Fingerprint

suspended load
bedload
deltaic deposit
landslide
bedrock
dam
lake
river
aggradation
gneiss
lacustrine deposit
energetics
mountain
sediment
Dams
Rivers
rate
Nepal
Sediment
Energetics

Keywords

  • Bedload
  • Bedrock incision
  • Himalaya
  • Landslide dam
  • Nepal
  • Suspended load

ASJC Scopus subject areas

  • Earth-Surface Processes
  • Earth and Planetary Sciences(all)

Cite this

Bedload-to-suspended load ratio and rapid bedrock incision from Himalayan landslide-dam lake record. / Pratt-Sitaula, Beth; Garde, Michelle; Burbank, Douglas W.; Oskin, Michael; Heimsath, Arjun; Gabet, Emmanuel.

In: Quaternary Research, Vol. 68, No. 1, 07.2007, p. 111-120.

Research output: Contribution to journalArticle

Pratt-Sitaula, Beth ; Garde, Michelle ; Burbank, Douglas W. ; Oskin, Michael ; Heimsath, Arjun ; Gabet, Emmanuel. / Bedload-to-suspended load ratio and rapid bedrock incision from Himalayan landslide-dam lake record. In: Quaternary Research. 2007 ; Vol. 68, No. 1. pp. 111-120.
@article{08736784ba6841d3b68d3bf86cc6c8a0,
title = "Bedload-to-suspended load ratio and rapid bedrock incision from Himalayan landslide-dam lake record",
abstract = "About 5400 cal yr BP, a large landslide formed a > 400-m-tall dam in the upper Marsyandi River, central Nepal. The resulting lacustrine and deltaic deposits stretched > 7 km upstream, reaching a thickness of 120 m. 14C dating of 7 wood fragments reveals that the aggradation and subsequent incision occurred remarkably quickly (∼ 500 yr). Reconstructed volumes of lacustrine (∼ 0.16 km3) and deltaic (∼ 0.09 km3) deposits indicate a bedload-to-suspended load ratio of 1:2, considerably higher than the ≤ 1:10 that is commonly assumed. At the downstream end of the landslide dam, the river incised a new channel through ≥ 70 m of Greater Himalayan gneiss, requiring a minimum bedrock incision rate of 13 mm/yr over last 5400 yr. The majority of incision presumably occurred over a fraction of this time, suggesting much higher rates. The high bedload ratio from such an energetic mountain river is a particularly significant addition to our knowledge of sediment flux in orogenic environments.",
keywords = "Bedload, Bedrock incision, Himalaya, Landslide dam, Nepal, Suspended load",
author = "Beth Pratt-Sitaula and Michelle Garde and Burbank, {Douglas W.} and Michael Oskin and Arjun Heimsath and Emmanuel Gabet",
year = "2007",
month = "7",
doi = "10.1016/j.yqres.2007.03.005",
language = "English (US)",
volume = "68",
pages = "111--120",
journal = "Quaternary Research",
issn = "0033-5894",
publisher = "Academic Press Inc.",
number = "1",

}

TY - JOUR

T1 - Bedload-to-suspended load ratio and rapid bedrock incision from Himalayan landslide-dam lake record

AU - Pratt-Sitaula, Beth

AU - Garde, Michelle

AU - Burbank, Douglas W.

AU - Oskin, Michael

AU - Heimsath, Arjun

AU - Gabet, Emmanuel

PY - 2007/7

Y1 - 2007/7

N2 - About 5400 cal yr BP, a large landslide formed a > 400-m-tall dam in the upper Marsyandi River, central Nepal. The resulting lacustrine and deltaic deposits stretched > 7 km upstream, reaching a thickness of 120 m. 14C dating of 7 wood fragments reveals that the aggradation and subsequent incision occurred remarkably quickly (∼ 500 yr). Reconstructed volumes of lacustrine (∼ 0.16 km3) and deltaic (∼ 0.09 km3) deposits indicate a bedload-to-suspended load ratio of 1:2, considerably higher than the ≤ 1:10 that is commonly assumed. At the downstream end of the landslide dam, the river incised a new channel through ≥ 70 m of Greater Himalayan gneiss, requiring a minimum bedrock incision rate of 13 mm/yr over last 5400 yr. The majority of incision presumably occurred over a fraction of this time, suggesting much higher rates. The high bedload ratio from such an energetic mountain river is a particularly significant addition to our knowledge of sediment flux in orogenic environments.

AB - About 5400 cal yr BP, a large landslide formed a > 400-m-tall dam in the upper Marsyandi River, central Nepal. The resulting lacustrine and deltaic deposits stretched > 7 km upstream, reaching a thickness of 120 m. 14C dating of 7 wood fragments reveals that the aggradation and subsequent incision occurred remarkably quickly (∼ 500 yr). Reconstructed volumes of lacustrine (∼ 0.16 km3) and deltaic (∼ 0.09 km3) deposits indicate a bedload-to-suspended load ratio of 1:2, considerably higher than the ≤ 1:10 that is commonly assumed. At the downstream end of the landslide dam, the river incised a new channel through ≥ 70 m of Greater Himalayan gneiss, requiring a minimum bedrock incision rate of 13 mm/yr over last 5400 yr. The majority of incision presumably occurred over a fraction of this time, suggesting much higher rates. The high bedload ratio from such an energetic mountain river is a particularly significant addition to our knowledge of sediment flux in orogenic environments.

KW - Bedload

KW - Bedrock incision

KW - Himalaya

KW - Landslide dam

KW - Nepal

KW - Suspended load

UR - http://www.scopus.com/inward/record.url?scp=34250782738&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34250782738&partnerID=8YFLogxK

U2 - 10.1016/j.yqres.2007.03.005

DO - 10.1016/j.yqres.2007.03.005

M3 - Article

AN - SCOPUS:34250782738

VL - 68

SP - 111

EP - 120

JO - Quaternary Research

JF - Quaternary Research

SN - 0033-5894

IS - 1

ER -