Early and middle Miocene ice sheet dynamics in the Ross Sea: Results from integrated core-log-seismic interpretation


Contact
Gerhard.Kuhn [ at ] awi.de

Abstract

Oscillations in ice sheet extent during early and middle Miocene are intermittently preserved in the sedimentary record from the Antarctic continental shelf, with widespread erosion occurring during major ice sheet advances, and open marine deposition during times of ice sheet retreat. Data from seismic reflection surveys and drill sites from Deep Sea Drilling Project Leg 28 and International Ocean Discovery Program Expedition 374, located across the present-day middle continental shelf of the central Ross Sea (Antarctica), indicate the presence of expanded early to middle Miocene sedimentary sections. These include the Miocene climate optimum (MCO ca. 17−14.6 Ma) and the middle Miocene climate transition (MMCT ca. 14.6−13.9 Ma). Here, we correlate drill core records, wireline logs and reflection seismic data to elucidate the depositional architecture of the continental shelf and reconstruct the evolution and variability of dynamic ice sheets in the Ross Sea during the Miocene. Drill-site data are used to constrain seismic isopach maps that document the evolution of different ice sheets and ice caps which influenced sedimentary processes in the Ross Sea through the early to middle Miocene. In the early Miocene, periods of localized advance of the ice margin are revealed by the formation of thick sediment wedges prograding into the basins. At this time, morainal bank complexes are distinguished along the basin margins suggesting sediment supply derived from marine-terminating glaciers. During the MCO, biosiliceous-bearing sediments are regionally mapped within the depocenters of the major sedimentary basin across the Ross Sea, indicative of widespread open marine deposition with reduced glacimarine influence. At the MMCT, a distinct erosive surface is interpreted as representing large-scale marine-based ice sheet advance over most of the Ross Sea paleo-continental shelf. The regional mapping of the seismic stratigraphic architecture and its correlation to drilling data indicate a regional transition through the Miocene from growth of ice caps and inland ice sheets with marine-terminating margins, to widespread marine-based ice sheets extending across the outer continental shelf in the Ross Sea.



Item Type
Article
Authors
Divisions
Primary Division
Programs
Primary Topic
Publication Status
Published
Eprint ID
54088
DOI 10.1130/b35814.1

Cite as
Pérez, L. F. , De Santis, L. , McKay, R. M. , Larter, R. D. , Ash, J. , Bart, P. J. , Böhm, G. , Brancatelli, G. , Browne, I. , Colleoni, F. , Dodd, J. P. , Geletti, R. , Harwood, D. M. , Kuhn, G. , Sverre Laberg, J. , Leckie, R. M. , Levy, R. H. , Marschalek, J. , Mateo, Z. , Naish, T. R. , Sangiorgi, F. , Shevenell, A. E. , Sorlien, C. C. , van de Flierdt, T. and 374 Scientists, I. O. D. P. E. (2021): Early and middle Miocene ice sheet dynamics in the Ross Sea: Results from integrated core-log-seismic interpretation , GSA Bulletin . doi: 10.1130/b35814.1


Share
Add to AnyAdd to TwitterAdd to FacebookAdd to LinkedinAdd to PinterestAdd to Email


Citation

Geographical region

Research Platforms
N/A

Campaigns
N/A


Actions
Edit Item Edit Item