Miocene glacial dynamics recorded by variations in magnetic properties in the ANDRILL AND-2 drill core

DOI

During the 2007 ANDRILL campaign in the Ross Sea, Antarctica, the AND-2A core was recovered through a stratigraphic succession spanning 1138.54 m of Neogene sedimentary rocks that include an expanded Early to Middle Miocene sequence. The study reported here focuses on the magnetic properties of the interval from 778.63 meters below sea floor (mbsf) to 1138.54 mbsf, which comprises a time interval spanning 1.5 Myr, from ~18.7 to ~20.2 Ma. We recognise three main pulses of increased input of magnetic materials to the drill site between 778.34 - 903.06, 950.55 - 995.78 and 1040 - 1103.96 mbsf. Trends in magnetic mineral concentration dependent parameters mirror changes in the proportion of sediments derived from McMurdo Volcanic Group rocks. We suggest these pulses in magnetic mineral concentration reflect changes in sediment transport processes associated with changing glacial conditions at the drill site that included (1) subglacial and grounding zone proximal settings, (2) hemipelagic and neritic conditions with abundant sediment-rich icebergs, (3) grounding zone-distal environment that was covered by land-fast multi-year sea-ice or a fringing ice shelf. The magnetic minerals record preserved in the AND-2A core supports other data that indicate a highly dynamic and variable coastal environment during the Early Miocene, where glaciers retreated inland under warm climatic conditions and advanced beyond the drill site across the continental shelf when cold climate prevailed.

Supplement to: Jovane, Luigi; Florindo, Fabio; Acton, Gary D; Ohneiser, Christian; Sagnotti, Leonardo; Strada, Eleonora; Verosub, Kenneth Lee; Wilson, Gary S; Iacoviello, Francesco; Levy, Richard H; Passchier, Sandra (2019): Miocene Glacial Dynamics Recorded by Variations in Magnetic Properties in the ANDRILL‐2A Drill Core. Journal of Geophysical Research: Solid Earth, 124(3), 2297-2312

Identifier
DOI https://doi.org/10.1594/PANGAEA.897964
Related Identifier https://doi.org/10.1029/2018JB016865
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.897964
Provenance
Creator Luigi, Jovane; Florindo, Fabio ORCID logo; Acton, Gary D ORCID logo; Ohneiser, Christian ORCID logo; Sagnotti, Leonardo (ORCID: 0000-0003-3944-201X); Strada, Eleonora; Verosub, Kenneth Lee; Wilson, Gary S ORCID logo; Iacoviello, Francesco ORCID logo; Levy, Richard H ORCID logo; Passchier, Sandra ORCID logo
Publisher PANGAEA
Publication Year 2019
Rights Creative Commons Attribution 4.0 International; https://creativecommons.org/licenses/by/4.0/
OpenAccess true
Representation
Resource Type Supplementary Publication Series of Datasets; Collection
Format application/zip
Size 6 datasets
Discipline Earth System Research
Spatial Coverage (165.277 LON, -77.758 LAT); McMurdo Sound
Temporal Coverage Begin 2007-10-10T12:00:00Z
Temporal Coverage End 2007-11-30T12:00:00Z