Date (Creation)

2024-04-25

Date (Revision)

2024-04-25

Date (Publication)

2024-04-25

Date (released)

2024-04-25

Edition

1.0

Unique resource identifier

https://doi.org/10.5285/1efc0048-5f0f-4ae7-a3a6-7728fe2ccf48

Codespace

doi

Unique resource identifier

GB/NERC/BAS/PDC/01840

Codespace

https://data.bas.ac.uk/

Unique resource identifier

NE/S006710/1

Codespace

award

Unique resource identifier

NE/K012088/1

Codespace

award

Unique resource identifier

NE/S006753/1

Codespace

award

Unique resource identifier

NE/K011278/1

Codespace

award

Other citation details

Please cite this item as: Nichols, K., Roberts, S., Rood, D., Johnson, J., Wilcken, K., & Brown, K. (2024). Cosmogenic Be-10 and Al-26 data and calculated surface exposure ages for cobbles collected from a moraine adjacent to Mount Murphy, West Antarctica (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/1efc0048-5f0f-4ae7-a3a6-7728fe2ccf48

Credit

No credit.

Status

Completed

Point of contact

Organisation name	Individual name	Electronic mail address	Role
Imperial College London	Nichols, Keir		Author
British Antarctic Survey	Roberts, Stephen		Author
Imperial College London	Rood, Dylan		Author
British Antarctic Survey	Johnson, Joanne		Author
Australian Nuclear Science and Technology Organisation	Wilcken, Klaus		Author
University College London	Brown, Katie		Author
NERC EDS UK Polar Data Centre		PDCServiceDesk@bas.ac.uk	Point of contact

Maintenance and update frequency

As needed

Maintenance note

Completed

Global Change Master Directory (GCMD) Science Keywords

• EARTH SCIENCE > Cryosphere > Glaciers/Ice Sheets > Glacier Thickness/Ice Sheet Thickness
• EARTH SCIENCE > Cryosphere > Glaciers/Ice Sheets > Glaciers
• EARTH SCIENCE > Cryosphere > Glaciers/Ice Sheets > Ice Sheets
• EARTH SCIENCE > Paleoclimate > Land Records > Isotopes
• EARTH SCIENCE > Solid Earth > Geochemistry > Isotopes

Theme

• Antarctica

• Glacial geology

• Holocene

• Pope Glacier

• Surface exposure ages

• Thwaites Glacier

• West Antarctic Ice Sheet

Place

• West Antarctica Antarctica

• Mount Murphy Antarctica

• Thwaites Glacier Antarctica

• Pope Glacier Antarctica

• Amundsen Sea Embayment Antarctica

GEMET - INSPIRE themes, version 1.0

• Elevation
• Geology

Access constraints

Other restrictions

Other constraints

no limitations to public access

Access constraints

Other restrictions

Other constraints

no limitations

Use constraints

License

Other constraints

Open Government Licence v3.0

Use constraints

Other restrictions

Other constraints

This data is governed by the NERC Data Policy: https://www.ukri.org/who-we-are/nerc/our-policies-and-standards/nerc-data-policy/

Use constraints

Other restrictions

Other constraints

This data is governed by the NERC data policy and supplied under Open Government Licence v.3

Use constraints

Other restrictions

Other constraints

No restrictions apply.

Unique resource identifier

url

Codespace

url

Association Type

Cross reference

Spatial representation type

Text, table

Language

English

Character set

UTF8

Topic category

• Climatology, meteorology, atmosphere
• Geoscientific information

Begin date

2016-01-07

End date

2016-01-07

Supplemental Information

It is recommended that careful attention be paid to the contents of any data, and that the author be contacted with any questions regarding appropriate use. If you find any errors or omissions, please report them to polardatacentre@bas.ac.uk.

Title

European Petroleum Survey Group (EPSG) Geodetic Parameter Registry

Date (Publication)

2008-11-12

Cited responsible party

Organisation name	Individual name	Electronic mail address	Role
European Petroleum Survey Group		EPSGadministrator@iogp.org	Publisher

Unique resource identifier

urn:ogc:def:crs:EPSG::3031

Version

6.18.3

Hierarchy level

Dataset

Statement

Methodology:

Samples (cobbles located on the surface of a moraine adjacent to Mount Murphy, West Antarctica) were collected by Dr Stephen J. Roberts (British Antarctic Survey) during the 2015-2016 austral summer. Laboratory chemistry was conducted in the CosmIC Laboratory at Imperial College London. Quartz purification followed the methods of Kohl and Nishiizumi (1992). Isotope dilution chemistry and beryllium and aluminium purification followed the methods of Corbett et al. (2016). Be-10/Be-9 and Al-26/Al-27 ratios were measured by accelerator mass spectrometry at ANSTO using the methods of Wilcken et al. (2017) and normalised to the standard values of Nishiizumi et al. (2007) and Nishiizumi (2004), respectively. Laboratory data were then converted to Be-10 or Al-26 concentrations and, finally, exposure ages using an online exposure age calculator (Balco et al., 2008). Exposure ages were calculated using the default global production rate and two different cosmogenic nuclide scaling methods (known as St (or Stone) and LSDn). The ages were also calculated assuming no erosion, using the Antarctic-specific (ant) elevation/pressure relationship, and the topographic shielding and sample thickness values in sample_information.csv.

Samples were collected in the field on 2016-01-07. Be ratios were measured on 2022-10-19 and Al ratios were measured on 2023-6-5.

Data collection:

Exposure ages were calculated using version 3 of the online exposure age calculators available at http://hess.ess.washington.edu.

Data quality:

Quartz purity was tested using inductively coupled plasma optical emission spectrometry (ICP-OES). For isotope dilution chemistry, one procedural blank (beryllium and aluminium carrier processed with no quartz) was processed with each batch of 11 samples. Because the five samples in this dataset were processed across two batches of samples (along with other Antarctic surface samples), there are two procedural blanks in this dataset that are used to correct Be-10 and Al-26 concentrations. Be-10 concentrations were corrected using the mean and standard deviation (SD) of two blanks (Be-9/Be-10 ratios: mean 2.71 x 10-15, SD 3.61 x 10-16, or Be-10 atoms: mean 47410 ± SD 6255). Al-26 concentrations were corrected using the weighted average and standard error of the measured ratios of two blanks as well as two carrier blanks (Al-26/Al-27 ratios: weighted average 7.79 x 10-16, SE 1.54 x 10-16). This weighted average Al-26/Al-27 ratio is used with the mass of carrier used with each quartz sample to calculate the background correction (in number of Al-26 atoms) for each Al-26 concentration. In other words, the blank correction for the Al-26 concentrations scales with the amount of aluminium carrier used. These values range from 34,573 to 43,757 Al-26 atoms and are found in '26Al blank (atoms/sample)' and '26Al blank (atoms/sample) ±' columns of Al_analytical_data_and_ages.csv. Carrier blanks are ~2.5 mg of aluminium carrier precipitated with the two process blanks above, but with no prior steps (quartz dissolution, isotope dilution chemistry). We also processed one aliquot of the laboratory intercomparison material CRONUS A (sample ID STDA050922 in the data tables).

Metadata

File identifier

1efc0048-5f0f-4ae7-a3a6-7728fe2ccf48 XML

Metadata language

English

Character set

UTF8

Hierarchy level

Dataset

Hierarchy level name

dataset

Date stamp

2024-04-25

Metadata standard name

ISO 19115 Geographic Information - Metadata

Metadata standard version

ISO 19115:2003(E)

Metadata author

Organisation name	Individual name	Electronic mail address	Role
NERC EDS UK Polar Data Centre		polardatacentre@bas.ac.uk	Point of contact