Summary of 40Ar/39Ar results from core sediment CRP-1 (Table 1)

40Ar/39Ar dating of volcanic clasts and pumice provide constraints for depositional ages of the CRP-1 core. Laser-fusion analyses of anorthoclase phenocrysts from pumice clasts concentrated near 116 mbsf suggest a depositional age of 18.40 ± 1.12 Ma (± 2). Results from anorthoclase phenocrysts and groundmass concentrates from five clasts of reworked lava provide maximum depositional ages of 19.73 ± 0.86 Ma to 17.15 ± 0.80 Ma for the 61 to 114 mbsf interval of CRP-1. The most precise age determination is 19.32 ± 0.14 Ma for the trachytic clasts near 105 mbsf. Taken together, the 40Ar/39Ar results from the lower part of CRP-1 suggest that none of the sediment above 116 mbsf is older than 19.5 Ma, and the data are most compatible with rapid accumulation of the 61 to 116 mbsf segment of CRP-1 near 18 Ma. 40AR/39Ar results from a basaltic clast from the carbonate-rich layer at 33 mbsf provide a maximum depositional age of 1.2 ± 0.1 Ma for this horizon.

Supplement to: McIntosh, W C (1998): 40Ar/39Ar geochronology of volcanic clasts and pumice in CRP-1 core, Cape Roberts, Antarctica. Terra Antartica, 5(3), 683-690

Identifier
DOI https://doi.org/10.1594/PANGAEA.54737
PID https://hdl.handle.net/10013/epic.28322.d001
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.54737
Provenance
Creator McIntosh, W C; McIntosh, Bill
Publisher PANGAEA
Publication Year 1998
Rights Creative Commons Attribution 3.0 Unported; https://creativecommons.org/licenses/by/3.0/
OpenAccess true
Representation
Resource Type Supplementary Dataset; Dataset
Format text/tab-separated-values
Size 80 data points
Discipline Earth System Research
Spatial Coverage (163.755 LON, -77.008 LAT); off Cape Roberts, Ross Sea, Antarctica
Temporal Coverage Begin 1997-10-17T01:30:00Z
Temporal Coverage End 1997-10-24T02:00:00Z