Straight from the source's mouth: Controls on field‐constrained sediment export across the entire active Corinth Rift, central Greece
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
The volume and grain‐size of sediment supplied from catchments fundamentally control basin stratigraphy. Despite their importance, few studies have constrained sediment budgets and grain‐size exported into an active rift at the basin scale. Here, we used the Corinth Rift as a natural laboratory to quantify the controls on sediment export within an active rift. In the field, we measured the hydraulic geometries, surface grain‐sizes of channel bars and full‐weighted grain‐size distributions of river sediment at the mouths of 47 catchments draining the rift (constituting 83% of the areal extent). Results show that the sediment grain‐size increases westward along the southern coast of the Gulf of Corinth, with the coarse‐fraction grain‐sizes (84th percentile of weighted grain‐size distribution) ranging from approximately 19 to 91 mm. We find that the median and coarse‐fraction of the sieved grain‐size distribution are primarily controlled by bedrock lithology, with late Quaternary uplift rates exerting a secondary control. Our results indicate that grain‐size export is primarily controlled by the input grain‐size within the catchment and subsequent abrasion during fluvial transport, both quantities that are sensitive to catchment lithology. We also demonstrate that the median and coarse‐fraction of the grain‐size distribution are predominantly transported in bedload; however, typical sand‐grade particles are transported as suspended load at bankfull conditions, suggesting disparate source‐to‐sink transit timescales for sand and gravel. Finally, we derive both a full Holocene sediment budget and a grain‐size‐specific bedload discharged into the Gulf of Corinth using the grain‐size measurements and previously published estimates of sediment fluxes and volumes. Results show that the bedload sediment budget is primarily comprised (~79%) of pebble to cobble grade (0.475–16 cm). Our results suggest that the grain‐size of sediment export at the rift scale is particularly sensitive to catchment lithology and fluvial mophodynamics, which complicates our ability to make direct inferences of tectonic and palaeoenvironmental forcing from local stratigraphic characteristics.
Date Issued
2020-12-01
Date Acceptance
2020-02-27
Citation
Basin Research, 2020, 32 (6), pp.1600-1625
ISSN
0950-091X
Publisher
Wiley
Start Page
1600
End Page
1625
Journal / Book Title
Basin Research
Volume
32
Issue
6
Copyright Statement
© 2020 The Authors. Basin Research published by International Association of Sedimentologists and European Association of Geoscientists and Engineers and John Wiley & Sons Ltd.
This is an open access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
This is an open access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Sponsor
Royal Society Research Grant
Identifier
https://onlinelibrary.wiley.com/doi/full/10.1111/bre.12444
Subjects
Science & Technology
Physical Sciences
Geosciences, Multidisciplinary
Geology
Corinth Rift
grain-size
sediment transport
bedload
sediment export
sediment budget
EASTERN ELIKI FAULT
GRAIN-SIZE
TECTONOSEDIMENTARY EVOLUTION
STRATIGRAPHIC ARCHITECTURE
SUSPENDED-LOAD
CLIMATE-CHANGE
SIERRA-NEVADA
WESTERN GULF
GREAT-PLAINS
SLIP RATES
Geology
04 Earth Sciences
Publication Status
Published
Date Publish Online
2020-03-03