Predicting sediment discharges and erosion rates in deep time—examples from the late Cretaceous North American continent

Abstract

Depositional stratigraphy represents the only physical archive of palaeo-sediment routing and this limits analysis of ancient source-to-sink systems in both space and time. Here, we use palaeo-digital elevation models (palaeoDEMs; based on highresolution palaeogeographic reconstructions), HadCM3L general circulation model climate data and the BQART suspended sediment discharge model to demonstrate a predictive, forward approach to palaeo-sediment routing system analysis. To exemplify our approach, we use palaeoDEMs and HadCM3L data to predict the configurations, geometries and climates of large continental catchments in the Cenomanian and Turonian North American continent. Then, we use BQART to estimate suspended sediment discharges and catchment-averaged erosion rates and we map their spatial distributions. We validate our estimates with published geologic constraints from the Cenomanian Dunvegan Formation, Alberta, Canada, and the Turonian Ferron Sandstone, Utah, USA, and find that estimates are consistent or within a factor of two to three. We then evaluate the univariate and multivariate sensitivity of our estimates to a range of uncertainty margins on palaeogeographic and palaeoclimatic boundary conditions; large uncertainty margins (≤50%/±5°C) still recover estimates of suspended sediment discharge within an order of magnitude of published constraints. PalaeoDEMs are therefore suitable as a first-order investigative tool in palaeo-sediment routing system analysis and are particularly useful where stratigraphic records are incomplete. We highlight the potential of this approach to predict the global spatio-temporal response of suspended sediment discharges and catchment-averaged erosion rates to long-period tectonic and climatic forcing in the geologic past.

Formation binning: a new method for increased temporal resolution in regional studies, applied to the Late Cretaceous dinosaur fossil record of North America

“…2019; Lyster et al . 2020), increasing the likelihood of fossil preservation. In contrast, whilst several transgressive marine tongues are observed within the Hell Creek formation (Fastovsky & Bercovici 2016), the Maastrichtian overall saw a retreat of the WIS, with possible east–west land connection between the two North American subcontinents (Slattery et al .…”

Reconstructing the morphologies and hydrodynamics of ancient rivers from source to sink: Cretaceous Western Interior Basin, Utah, USA

“…As such, these reconstruction tools are not appropriate, by themselves, for reconstructing the total sediment load of a wash load-dominated system, for example. Knowledge of prevailing sediment transport modes is important for evaluating whether different sediment discharge reconstruction methods are consistent with one another, as studies that reconstruct sediment discharges often corroborate results with an independent approach (Lin & Bhattacharya, 2017;Watkins et al, 2018;Zhang et al, 2018;Brewer et al, 2020;Lyster et al, 2020).…”

“…A key research challenge is to decode this archive to reconstruct the movement of water and sediment across Earth's surface in the geological past (Castelltort & Van Den Driessche, 2003;Jerolmack & Paola, 2010;Ganti et al, 2014;Romans et al, 2016;Straub et al, 2020) -effective quantification of palaeohydrology from fluvial stratigraphy is crucial to achieve this goal. Constraints on the morphologies and hydrodynamics of palaeorivers can be used to: resolve the size and scale of ancient catchments (Bhattacharya & Tye, 2004;Bhattacharya et al, 2016;Eide et al, 2018;Lyster et al, 2020); quantify sediment transport capacities and the magnitudes of sediment exported to oceans (Allen et al, 2013;Holbrook & Wanas, 2014;Lin & Bhattacharya, 2017;Sharma et al, 2017); decipher fluvial response to perturbation (Foreman et al, 2012;Foreman, 2014;Colombera et al, 2017;Chen et al, 2018); and reconstruct local palaeogeographies (Li et al, 2018). Importantly, these constraints can be used to investigate hydrological response to long-period forcing (>10 6 yrs) as river behaviour is intrinsically linked to tectono-climatic boundary conditions over geological timescales (Duller et al, 2010;Whitchurch et al, 2011;Whittaker et al, 2011;Castelltort et al, 2012;.…”

Assessing first‐order BQART estimates for ancient source‐to‐sink mass budget calculations

“…The advantage of using Equation ( 5) is that the full possible range in water discharge for each climate zone is captured as opposed to a single averaged value (Table 2). Alternatively, paleoclimate modelling (e.g., Armstrong et al, 2016;Jacob et al, 2001;Sellwood & Valdes, 2008) can provide a useful tool to reconstruct the catchment-wide climate conditions, including precipitation, to define paleo-water discharge for the Q parameter as demonstrated recently by Lyster et al (2020).…”

“…Helland-Hansen et al (2016) notes that the approach does not capture the low-frequency, high-amplitude events which may dominate a significant portion of sediment transport and deposition on geological timescales. In addition, the method does not account for bedload material and appears more sensitive to uncertainty in temperature of cooler climates (Lyster et al, 2020). Analytically, catchment area is the largest potential source of uncertainty ranging five orders of magnitude (Eide, Klausen, et al, 2018) and combined with estimation of catchment relief is suggested to be the largest uncertainty in the BQART model for ancient S2S studies (Brewer et al, 2020).…”