UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Detrital Thermochronometry Reveals That the Topography Along the Antarctic Peninsula is Not a Pleistocene Landscape

Clinger, AE; Fox, M; Balco, G; Cuffey, K; Shuster, DL; (2020) Detrital Thermochronometry Reveals That the Topography Along the Antarctic Peninsula is Not a Pleistocene Landscape. Journal of Geophysical Research: Earth Surface , 125 (6) , Article e2019JF005447. 10.1029/2019JF005447. Green open access

[thumbnail of Fox_2019JF005447.pdf]
Preview
Text
Fox_2019JF005447.pdf - Published Version

Download (3MB) | Preview

Abstract

Using offshore detrital apatite (U‐Th)/He thermochronometry and 3D thermo‐kinematic modeling of the catchment topography, we constrain the timing of major topographic change at Bourgeois Fjord, Antarctic Peninsula (AP). While many mid‐latitude glacial landscapes developed primarily in response to global cooling over the last ~2.6 Ma, we find that kilometer‐scale landscape evolution at Bourgeois Fjord began ~30–12 Ma ago and <2 km of valley incision has occurred since ~16 Ma. This early onset of major topographic change occurred following the initiation of alpine glaciation at this location and prior to the development of a regional polythermal ice sheet inferred from sedimentary evidence offshore of the AP. We hypothesize that topographic change relates to (i) feedbacks between an evolving topography and glacial erosion processes, (ii) effects of glacial‐interglacial variability, and (iii) the prevalence of subglacial meltwater. The timing and inferred spatial patterns of long‐term exhumation at Bourgeois Fjord are consistent with a hypothesis that glacial erosion processes were suppressed at the AP during global Plio‐Pleistocene cooling, rather than enhanced. Our study examines the long‐term consequences of glacial processes on catchment‐wide erosion as the local climate cooled. Our findings support the hypothesis that landscapes at different latitudes had different responses to global cooling. Our results also suggest that erosion is enhanced along the plateau flanks of Bourgeois Fjord today, which may be due to periglacial processes or mantling via subglacial till. If regional warming persists and meltwater becomes more pronounced, we predict that enhanced erosion along the plateau flank will accelerate topographic change.

Type: Article
Title: Detrital Thermochronometry Reveals That the Topography Along the Antarctic Peninsula is Not a Pleistocene Landscape
Open access status: An open access version is available from UCL Discovery
DOI: 10.1029/2019JF005447
Publisher version: https://doi.org/10.1029/2019JF005447
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Earth Sciences
URI: https://discovery.ucl.ac.uk/id/eprint/10106833
Downloads since deposit
57Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item