Environmental signal propagation in sedimentary systems across timescales

Abstract

15Earth-surface processes operate across erosionally dominated landscapes and 16 deliver sediment to depositional systems that can be preserved over a range of timescales. 17

The geological significance of cosmogenic nuclides in large lowland river basins

“…Thus a mean, representative orogenic denudation rate can be derived 785 from a bag of sediment sampled downstream. This decrease in variation is most 786 likely due to larger catchments being more representative of sediment transport 787 processes than smaller catchments, especially if a transfer zone is present in a basin 788 that is able to retain sediment for longer periods (Romans et al, 2015). "buffer" against these changes.…”

“…When compared 79 with sediment gauging data, integrating over the past few decades, we can use the 80 cosmogenic nuclide data to evaluate the temporal stability of sediment transport 81 and thus source-sink connectivity. As recently reviewed by Romans et al (2015) the 82 stratigraphic record of source to sink sediment transfer records signals of external 83 environmental forcings as well as internal sedimentary dynamics. To make use of 84 this record it is of high importance to understand how rivers transmit signals of 85 climate cycles and to estimate the fluvial preservation potential (Castelltort and Van 86 Den Driessche, 2003;Phillips, 2003;Allen, 2008;Jerolmack and Paola, 2010;87 Armitage et al, 2011;Simpson and Castelltort, 2012;Armitage et al, 2013;Godard 88 et al, 2013;Latrubesse, 2015).…”

Punctuated Sediment Discharge during Early Pliocene Birth of the Colorado River: Evidence from Regional Stratigraphy, Sedimentology, and Paleontology

“…However, competing processes such as sealevel rise, basin subsidence, and related sediment storage are capable of shutting down river sand discharge and driving regional retreat, or backstepping of large delta systems at geologic timescales (Swenson et al, 2000;Cattaneo and Steel, 2003;Catuneanu et al, 2009;Romans et al, 2016). Data presented above provide abundant evidence for punctuated sediment discharge during river initiation, so the question becomes: how and why did sand output from the Colorado River turn on, off, and on again in a ~ 1 million-year interval between ~5.4 and 4.4 Ma?…”

“…Interpretation of river-forming processes is informed by model-and fieldbased insights into controls on transfer of sediment from an eroding source through a river channel network (fluvial transfer subsystem) to the depositional sink ( Fig. 2; Paola et al, 1992;Paola, 2000;Castelltort and Van Den Driessche, 2003;Allen, 2008;Michael et al, 2013;Romans et al, 2016). Sediment discharge (qs) is defined as a material flux (mass/time, volume/time) that can be specified at any point along a river network from its upland source to basinal sink (e.g., Paola, 2000).…”

Linking an Early Triassic delta to antecedent topography: Source-to-sink study of the southwestern Barents Sea margin

“…It is also important in order to predict sedimentary environments and their link to catchments in areas with limited data (e.g., Sømme et al, 2009a), since it increases predictability in reservoir and hydrocarbon exploration (Martinsen et al, 2010). Investigating sediment mass balances for source-to-sink systems in deep time (≤10 8 yr) is challenging because factors such as tectonic regime and climate are poorly constrained, catchments are largely eroded, and resolution of dating methods is uncertain (e.g., Romans et al, 2016;Helland-Hansen et al, 2016). However, in the Early Triassic of the Barents Sea, several of these hampering issues are alleviated: Biostratigraphic dating has a relatively high resolution (~1 m.y.)…”