Indication of Holocene sea-level stability in the southern Laptev Sea recorded by beach ridges in north-east Siberia, Russia

Short communication: Driftwood provides reliable chronological markers in Arctic coastal deposits

“…Collected with a manually operated saw, the samples were stored in the field under well-aerated conditions and later cleaned in the laboratory and dried for at least 48 h at 45 • C. For stem discs, subsamples for 14 C dating were taken from the outermost preserved tree rings and submitted to the MICADAS radiocarbon dating laboratory of the Alfred Wegener Institute in Bremerhaven, Germany. A description of the sample preparation and dating protocol can be found in Sander et al (2019). The obtained 14 C ages were calibrated using OxCal 4.3 (Bronk Ramsey, 2009) and the IntCal13 calibration curve (Reimer et al, 2013).…”

“…For the two beachridge systems, Bayesian age-distance models (P sequences; Figs. S2 and S3) were constructed in OxCal 4.3 using the distance of each sample from the innermost preserved beach ridge as a spatial and chronological reference (Bronk Ramsey, 2008;Sander et al, 2019).…”

“…Wood transport in rivers is not particularly well-investigated and depends largely on catchment properties and runoff regime (Kramer and Wohl, 2017;Kramer et al, 2017). The few studies available suggest that residence times in watersheds are of the order of several years to centuries, with large uncertainties in the fate of the wood following recruitment (Swanson and Lienkaemper, 1978;Schenk et al, 2014;Alix, 2016). Once the driftwood has reached the ocean, it is often argued that sea-ice-bound transport across the Arctic occurs within a few years and that free-floating wood sinks over a matter of months (Häggblom, 1982;Dyke et al, 1997;Bennike, 2004;Funder et al, 2011).…”

“…Beach ridges form at locations along wave-dominated shorelines, where accommodation and sediment supply have been positive over extensive periods of time. Prograded beachridge systems and spits are recurrent features along the shoreline of the eastern Laptev Sea, but they remain largely unstudied (with the exception of Sander et al, 2019). In most cases, each visible ridge is a time-integrated feature formed during multiple periods of reworking rather than during an individual event (Tamura, 2012;Lindhorst and Schutter, 2014).…”

The turnaround from transgression to regression of Holocene barrier systems in south‐eastern Australia: Geomorphology, geological framework and geochronology

“…Unlike coastal settings in glacial forebulge regions, Australia has numerous Holocene prograded barrier systems that are dominated by net regressive sedimentary successions (Thom, 1983;Searle et al, 1988;Short et al, 1989;Roy et al, 1994;Murray-Wallace et al, 2002;Brooke et al, 2008a,b;Gontz et al, 2014;Oliver et al, 2015Oliver et al, , 2017aOliver et al, ,b,c, 2019Oliver et al, , 2020Dougherty et al, 2016Dougherty et al, , 2019aKinsela et al, 2016Kinsela et al, , 2020Tamura et al, 2018;Carvalho et al, 2019). Similar broad prograded barriers composed of a series of palaeoshoreline ridges are also common elsewhere on far-field coasts (see Scheffers et al, 2012); for example, along coasts in Brazil (Dillenburg & Hesp, 2009;Barboza et al, 2011;Dillenburg et al, 2017), Asia (Tamura et al, 2007;Brill et al, 2015) and Russia (Sander et al, 2019), as well as coasts experiencing isostatic rebound such as Denmark (Nielsen et al, 2006).…”