40Ar/39Ar geochronology data from basalt samples collected from the Macquarie Ridge Complex, including the exposed Macquarie Island and submarine dredge sites. Samples were collected during a 2017 field trip and the 2008 TAN0803 research voyage. Analyses were performed at the Western Australian Argon Isotope Facility at Curtin University, with data processed using ArArCALC software.
Use Cases
- Determine plateau ages for basalt samples using 39Ar release percentages and step-heating data.
- Calibrate irradiation standards (FCs, GA1550) against sample measurements to calculate isotopic ratios.
- Analyze the geochronology of different mineral separates (plagioclase, pyroxene, amphibole) from specific grain size fractions (125–212 μm, 212–355 μm).
- Assess the statistical confidence of age plateaus using probability of fit (P) criteria and 2σ uncertainty calculations.
- Correlate sample collection locations (Macquarie Island, submarine dredges) with calculated eruption or formation ages.
Strengths
- Data includes specific analytical criteria for plateau determination, requiring at least 70% of 39Ar released and a minimum of 3 consecutive steps.
- Samples were irradiated alongside two well-defined age standards (FCs: 28.294 ± 0.037 Ma, GA1550: 99.738 ± 0.100 Ma) for calibration.
Limitations
- Sample size and row count are unknown, limiting statistical assessment.
- The dataset's temporal coverage is limited to samples collected in 2008 and 2017, with no continuous time series.
Provenance
- Source
- AU_AADC (Australian Antarctic Data Centre), via NASA Earthdata.
- Collection Method
- Field collection from Macquarie Island and dredge sampling during research voyage TAN0803, followed by laboratory 40Ar/39Ar analysis using laser step-heating and mass spectrometry.
- Time Range
- Sample collection in 2008 and 2017.
- Freshness
- null
- Geography
- Macquarie Ridge Complex, specifically Macquarie Island and surrounding submarine areas.