Reconstructing the morphologies and hydrodynamics of ancient rivers from source to sink: Cretaceous Western Interior Basin, Utah, USA
File(s)sed.12877.pdf (12.54 MB)
Published version
Author(s)
Type
Journal Article
Abstract
Quantitative reconstruction of palaeohydrology from fluvial stratigraphy provides sophisticated insights into the response, and relative impact, of tectonic and climatic drivers on ancient fluvial landscapes. Here, field measurements and a suite of quantitative approaches are used to develop a four-dimensional (space and time) reconstruction of palaeohydrology in Late Cretaceous palaeorivers of central Utah, USA – these rivers drained the Sevier mountains to the Western Interior Seaway. Field data include grain-size and cross-set measurements and span five parallel fluvial systems, two of which include up-dip to down-dip transects, across seven stratigraphic intervals through the Blackhawk Formation, Castlegate Sandstone and Price River Formation. Reconstructed palaeohydrological parameters include fluvial morphologies (flow depths, palaeoslopes, palaeorelief and planform morphologies) and various hydrodynamic properties (flow velocities, water discharges and sediment transport modes). Results suggest that fluvial morphologies were similar in space and time; median flow depths spanned 2 to 4 m with marginally greater flow depths in southerly systems. Meanwhile palaeoslopes spanned 10−3 to 10−4, decreasing downstream by an order of magnitude. The most prominent spatio-temporal change is an up to four-fold increase in palaeoslope at the Blackhawk–Castlegate transition; associated alluvial palaeorelief is tens of metres during Blackhawk deposition and >100 m during Castlegate Sandstone deposition. This study observed no change in unit water discharges at the Blackhawk–Castlegate transition, which argues against a climatically driven increase in palaeoslope and channel steepness. These findings instead point to a tectonically driven palaeoslope increase, although one limitation in this study is uncertainty in palaeochannel widths, which directly influences total water discharges. These reconstructions complement and expand on extensive previous work in this region, which enables the efficacy of quantitative reconstruction tools to be tested. Comparison of results with facies-based interpretations indicates that quantitative tools work well, but inconsistencies in more complex reconstructions (for example, planform morphologies) highlight the need for further work.
Date Issued
2021-10-01
Date Acceptance
2021-03-25
Citation
Sedimentology, 2021, 68 (6), pp.2854-2886
ISSN
0037-0746
Publisher
Wiley
Start Page
2854
End Page
2886
Journal / Book Title
Sedimentology
Volume
68
Issue
6
Copyright Statement
© 2021 The Authors. Sedimentology published by John Wiley & Sons Ltd on behalf of International Association of Sedimentologists
This is an open access article under the terms of the Creative Commons Attribution License, 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, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
License URL
Identifier
https://onlinelibrary.wiley.com/doi/10.1111/sed.12877
Subjects
Science & Technology
Physical Sciences
Geology
Fluvial hydrodynamics
fluvial morphologies
Late Cretaceous
North America
palaeohydrology
palaeorivers
CORDILLERAN FORELAND BASIN
FLUVIAL SHEET SAND
WASATCH PLATEAU
BOOK-CLIFFS
CASTLEGATE SANDSTONE
BLACKHAWK FORMATION
GRAIN-SIZE
SEDIMENT-TRANSPORT
MASS-BALANCE
THRUST BELT
0403 Geology
Geology
Publication Status
Published
Article Number
sed.12877
Date Publish Online
2021-04-04