Abstract:
This dataset comprises U-Pb zircon geochronology data from six rock samples from the sub-Antarctic Island of South Georgia. The data were collected in the interval November 2023 to March 2024 at the University College London. The U-Pb analyses were conducted on six granitoid samples from across South Georgia to examine the age of magmatism and how they correlate with magmatism from the northern Antarctic Peninsula and southern South America.
This project was funded by NERC National Capability funding to the British Antarctic Survey's Paleo Environments, Ice Sheets and Climate Change team.
Keywords:
U-Pb, geochronology, zircon
Riley, T. (2025). Granite geochronology data from South Georgia (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/aeac83d8-b368-4152-9083-5956b84e348e
| Use Constraints: | This data is governed by the NERC data policy (http://www.nerc.ac.uk/research/sites/data/policy/) and supplied under Open Government Licence v.3 (http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/). |
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| Creation Date: | 2025-11-04 |
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| Dataset Progress: | Planned |
| Dataset Language: | English |
| ISO Topic Categories: |
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| Parameters: |
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| Personnel: | |
| Name | UK Polar Data Centre |
| Role(s) | Metadata Author |
| Organisation | British Antarctic Survey |
| Name | Teal R Riley |
| Role(s) | Technical Contact, Investigator |
| Organisation | British Antarctic Survey |
| Parent Dataset: | N/A |
| Reference: | Ludwig, K. R. (2012). User manual for Isoplot 3.75-4.15: a geochronological toolkit for Microsoft Excel. Berkeley Geochronology Centre Special Publications 5. Slama, J., Kosler, J., Condon, D. J., Crowley, J. L., Gerdes, A., Hanchar, J. M., Horstwood, M. S. A., Morris, G. A., Nasdala, L., Norberg, N., Schaltegger, U., Schoene, B., Tubrett, M. N., & Whitehouse, M. J. (2008). Plesovice zircon - a new natural reference material for U-Pb and Hf isotopic microanalysis. Chemical Geology, 249 (1-2), 1-35. Vermeesch, P. (2018). IsoplotR: a free and open toolbox for geochronology. Geoscience Frontiers, 9, 1479-1493. https://doi.10.1016/j.gsf.2018.04.001. |
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| Quality: | U-Pb ages were calculated using the 206Pb/238U ratios for samples dated as <1.1 Ga, and the 207Pb/206Pb ratios was used for older grains. Discordance was determined using (207Pb/235U - 206Pb/238U) / 206Pb/238U) and similar for 207Pb/206Pb ages. | |
| Lineage/Methodology: | Analytical methods: Zircon U-Pb geochronology University College London Zircon U-Pb geochronology used laser ablation inductively coupled mass spectrometry (LA-ICP-MS) facilities (Agilent 7700 coupled to a New Wave Research 193 nm excimer laser) at the London Geochronology Centre based in University College London. Heavy minerals were separated from bulk sediment samples using standard density liquid and magnetic separation procedures. Zircon-enriched extracts were mounted in hard epoxy resin on glass slides and polished for analysis. Typical laser spot sizes of 25 micrometers were used with a 7-10 Hz repetition rate and a fluence of 2.5 J/cm2. Background measurement before ablation lasted 15 seconds and laser ablation dwell time was 25 seconds. The external zircon standard was Plesovice, which has a TIMS reference age 337.13 +/- 0.37 Ma (Slama et al., 2008). Standard errors on isotope ratios and ages include the standard deviation of 206Pb/238U ages of the Plesovice standard zircon. Time-resolved signals that record isotopic ratios with depth in each crystal were processed using GLITTER 4.5, data reduction software, developed by the ARC National Key Centre for Geochemical Evolution and Metallogeny of Continents (GEMOC) at Macquarie University and CSIRO Exploration and Mining. Processing enabled filtering to remove spurious signals owing to overgrowth boundaries, weathering, inclusions, or fractures. |
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| Temporal Coverage: | |
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| Start Date | 2023-11-01 |
| End Date | 2024-03-31 |
| Spatial Coverage: | |
| Latitude | |
| Southernmost | -54.80261 |
| Northernmost | -54.46745 |
| Longitude | |
| Westernmost | -37.06932 |
| Easternmost | -35.80442 |
| Altitude | |
| Min Altitude | N/A |
| Max Altitude | N/A |
| Depth | |
| Min Depth | N/A |
| Max Depth | N/A |
| Location: | |
| Location | South Georgia Island |
| Detailed Location | N/A |
| Data Collection: | Data was processed using Isoplot 3.75-4.15 software (Ludwig 2012), IsoplotR (Vermeesch 2018) and GLITTER 4.5 |
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| Data Storage: | 7 x .csv files |
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