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How is topographic simplicity maintained in ephemeral dryland channels?

Research output: Contribution to journalArticle

DOI

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How is topographic simplicity maintained in ephemeral dryland channels? / Singer, Michael Bliss; Michaelides, Katerina.

In: Geology, Vol. 42, No. 12, 12.2014, p. 1091-1094.

Research output: Contribution to journalArticle

Harvard

Singer, MB & Michaelides, K 2014, 'How is topographic simplicity maintained in ephemeral dryland channels?' Geology, vol. 42, no. 12, pp. 1091-1094. https://doi.org/10.1130/G36267.1

APA

Singer, M. B., & Michaelides, K. (2014). How is topographic simplicity maintained in ephemeral dryland channels? Geology, 42(12), 1091-1094. https://doi.org/10.1130/G36267.1

Vancouver

Singer MB, Michaelides K. How is topographic simplicity maintained in ephemeral dryland channels? Geology. 2014 Dec;42(12):1091-1094. https://doi.org/10.1130/G36267.1

Author

Singer, Michael Bliss ; Michaelides, Katerina. / How is topographic simplicity maintained in ephemeral dryland channels?. In: Geology. 2014 ; Vol. 42, No. 12. pp. 1091-1094.

Bibtex - Download

@article{16b399adf4c8457bba66e7ed4a3f9f98,
title = "How is topographic simplicity maintained in ephemeral dryland channels?",
abstract = "The lack of topographic complexity in ephemeral dryland channels, despite large variations in hydraulic controls and sediment texture, presents an unexplained paradox that limits understanding of their long-term evolution. In dryland basins, spatially and temporally discontinuous channel flow transports and sorts sediment along the bed intermittently and irregularly. The cumulative effect of these processes counterintuitively produces simple topography, manifest in straight longitudinal profiles and symmetrical cross sections, in contrast with perennial channels. This paper presents numerical modeling experiments based on field measurements to investigate dryland channel topographic development through the responses of bed-material flux and net sediment storage to variations in channel hydrology. We show that spatially variable flow creates and subsequently destroys incipient topography along ephemeral reaches, and that large flood events above a threshold overcome hydraulic and grain-size controls to dampen fluctuations in longitudinal sediment flux through a smoothing of the incipient channel bar forms. The results provide a physical explanation for emergent topographic simplicity in ephemeral dryland channels despite higher variability in streamflow and sedimentary characteristics compared to perennial systems.",
author = "Singer, {Michael Bliss} and Katerina Michaelides",
note = "For publication fee support the authors thank National Science Foundation grant EAR-1226741 (to Singer).",
year = "2014",
month = "12",
doi = "10.1130/G36267.1",
language = "English",
volume = "42",
pages = "1091--1094",
journal = "Geology",
issn = "0091-7613",
publisher = "GEOLOGICAL SOC AMER, INC",
number = "12",

}

RIS (suitable for import to EndNote) - Download

TY - JOUR

T1 - How is topographic simplicity maintained in ephemeral dryland channels?

AU - Singer, Michael Bliss

AU - Michaelides, Katerina

N1 - For publication fee support the authors thank National Science Foundation grant EAR-1226741 (to Singer).

PY - 2014/12

Y1 - 2014/12

N2 - The lack of topographic complexity in ephemeral dryland channels, despite large variations in hydraulic controls and sediment texture, presents an unexplained paradox that limits understanding of their long-term evolution. In dryland basins, spatially and temporally discontinuous channel flow transports and sorts sediment along the bed intermittently and irregularly. The cumulative effect of these processes counterintuitively produces simple topography, manifest in straight longitudinal profiles and symmetrical cross sections, in contrast with perennial channels. This paper presents numerical modeling experiments based on field measurements to investigate dryland channel topographic development through the responses of bed-material flux and net sediment storage to variations in channel hydrology. We show that spatially variable flow creates and subsequently destroys incipient topography along ephemeral reaches, and that large flood events above a threshold overcome hydraulic and grain-size controls to dampen fluctuations in longitudinal sediment flux through a smoothing of the incipient channel bar forms. The results provide a physical explanation for emergent topographic simplicity in ephemeral dryland channels despite higher variability in streamflow and sedimentary characteristics compared to perennial systems.

AB - The lack of topographic complexity in ephemeral dryland channels, despite large variations in hydraulic controls and sediment texture, presents an unexplained paradox that limits understanding of their long-term evolution. In dryland basins, spatially and temporally discontinuous channel flow transports and sorts sediment along the bed intermittently and irregularly. The cumulative effect of these processes counterintuitively produces simple topography, manifest in straight longitudinal profiles and symmetrical cross sections, in contrast with perennial channels. This paper presents numerical modeling experiments based on field measurements to investigate dryland channel topographic development through the responses of bed-material flux and net sediment storage to variations in channel hydrology. We show that spatially variable flow creates and subsequently destroys incipient topography along ephemeral reaches, and that large flood events above a threshold overcome hydraulic and grain-size controls to dampen fluctuations in longitudinal sediment flux through a smoothing of the incipient channel bar forms. The results provide a physical explanation for emergent topographic simplicity in ephemeral dryland channels despite higher variability in streamflow and sedimentary characteristics compared to perennial systems.

U2 - 10.1130/G36267.1

DO - 10.1130/G36267.1

M3 - Article

VL - 42

SP - 1091

EP - 1094

JO - Geology

T2 - Geology

JF - Geology

SN - 0091-7613

IS - 12

ER -

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ID: 123987794