Topic
Palaeochannel
About: Palaeochannel is a research topic. Over the lifetime, 328 publications have been published within this topic receiving 6251 citations. The topic is also known as: paleochannel.
Papers published on a yearly basis
Papers
TL;DR: In this paper, the authors propose a sedimentary-architecture descriptive scheme that distinguishes elements from two stages of channel-fill development; (i) the abandonment stage with initial proximal fill, and (ii) the subsequent fully abandoned palaeochannel that collects distal fill.
Abstract: Channel fills are common elements of Holocene river systems and older fluvial sequences, but surprisingly little is known about formation and their sedimentary build-up. Abandoned channels result from channel shifting processes at various scales, including meander cutoff and channel-belt avulsion. Channel-fill sequences are of importance as containers of palaeoenvironmental proxy-records, can be used to reconstruct palaeochannel dynamics and derive palaeoflood records, and contain materials that allow dating the abandonment. Integrated knowledge on the dynamic nature (geometrical and physical insights) of channel abandonment and resultant sedimentary recording is a necessity for comparing and collating records from a series of abandoned channel fills.
This paper intends to make channel-fill sedimentological sequences more useful recorders of channel abandonment processes and palaeofloods, for which improved understanding is needed of the internal build-up of channel fills. We review oxbow lake infilling along meandering rivers, and supplement this with highly detailed descriptions of two selected field examples of channel fills from the apex-region of the Netherlands' Rhine delta. From these examples it becomes clear that regional setting and type of abandonment result in different channel-fill end-members; oxbow cutoffs generally produce thick laminated clayey fills as the channel entrance is plugged rapidly, avulsion-abandoned channels are filled with coarse (proximal) deposits as a result of a maintained open river connection.
Field examples of channel fills are integrated with knowledge on channel abandonment dynamics in meander cutoff and bifurcating river situations, including insights from recent numerical modelling. We propose a sedimentary-architecture descriptive scheme that distinguishes elements from two stages of channel-fill development; (i) the abandonment stage with initial proximal fill, and (ii) the subsequent fully abandoned palaeochannel that collects distal fill. Copyright © 2011 John Wiley & Sons, Ltd.
295 citations
Journal Article•
TL;DR: In this article, the geometry, flow, and sedimentary processes of the different channel patterns form a continuum, such that similarities between their deposits are more significant than differences, and the following criteria are considered useful: 1) proportion of channel fills relative to lateral-accretion deposits, which increases with degree of braiding; 2) mean grain size of channel fill relative to LAC deposits; 3) paleocurrent variance, which may indicate sinuosity; and 4) bankfull discharge, slo e, and width/depth of paleochannels throughout the channel belt
Abstract: Interpretation of paleochannel patterns from ancient alluvium involves reconstruction of sinuosity and degree of braiding. It is emphasized here that the geometry, flow, and sedimentary processes of the different channel patterns form a continuum, such that similarities between their deposits are more significant than differences. While many commonly cited sedimentary criteria for distinguishing channel patterns are shown to be invalid, the following are considered useful: 1) proportion of channel fills relative to lateral-accretion deposits, which increases with degree of braiding; 2) mean grain size of channel fills relative to lateral-accretion deposits, which decreases with increasing sinuosity; 3) paleocurrent variance, which may indicate sinuosity; and 4) bankfull discharge, slo e, and width/depth of paleochannels throughout the channel belt, as long as they can be quantitatively reconstructed from channel-bar and channel-fill deposits. Utilization of these criteria requires examination of completely preserved sections of channel belts and overbank deposits in large outcrops. Presently existing facies models do not convey the diversity of different channel types and facies; those that are not three-dimensional and lack scales and paleocurrent information are of limited value.
216 citations
TL;DR: In this paper, a Holocene alluvial archive of 506 dated units for Great Britain is analysed in terms of the sedimentation styles involved, and the database is classified by sedimentation unit (channel sediments, palaeochannel fills, floodplain surface sedimentiments, floodbasins and colluvial deposits).
159 citations
TL;DR: In this article, the geometry, flow, and sedimentary processes of the different channel patterns form a continuum, such that similarities between their deposits are more significant than differences, and the following criteria are considered useful: proportion of channel fills relative to lateral-accretion deposits, which increases with degree of braiding.
Abstract: Interpretation of paleochannel patterns from ancient alluvium involves reconstruction of sinuosity and degree of braiding. It is emphasized here that the geometry, flow, and sedimentary processes of the different channel patterns form a continuum, such that similarities between their deposits are more significant than differences. While many commonly cited sedimentary criteria for distinguishing channel patterns are shown to be invalid, the following are considered useful: 1) proportion of channel fills relative to lateral-accretion deposits, which increases with degree of braiding; 2) mean grain size of channel fills relative to lateral-accretion deposits, which decreases with increasing sinuosity; 3) paleocurrent variance, which may indicate sinuosity; and 4) bankfull discharge, slope, and width/depth of paleochannels throughout the channel belt, as long as they can be quantitatively reconstructed from channel-bar and channel-fill deposits. Utilization of these criteria requires examination of completely preserved sections of channel belts and overbank deposits in large outcrops. Presently existing facies models do not convey the diversity of different channel types and facies; those that are not three-dimensional and lack scales and paleocurrent information are of limited value.
153 citations
TL;DR: In this paper, a comparison between the Laingsburg flood deposits and fluvial sandstones of the Permian Lower Beaufort in the southwestern Karoo region of South Africa is made.
147 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2025 | 22 |
| 2024 | 17 |
| 2023 | 38 |
| 2022 | 49 |
| 2021 | 14 |
| 2020 | 18 |