9655249
Persistent Identifier: https://pid.geoscience.gov.au/sample/AU9655249
| Property | Value |
|---|---|
| id | 9655249 |
| igsn | 10.60494/ve47-xj35 |
| sample_id | 01RC183 |
| eno | 912544 |
| sampling_feature_name | 01RC183 |
| sampling_feature_type | field site |
| sample_type | outcrop specimen |
| sampling_method | outcrop sampling |
| material_class | rock |
| stratigraphic_unit | Reedy Creek Granodiorite |
| geological_province | Delamerian Orogen |
| sample_remark | Foden et al. (2006): Zircons were separated from the strongly foliated granodiorite (01RC183) and undeformed diorite (779-5) whose emplacement brackets the terminal Delamerian D3 deformation at Reedy Creek. These were subjected to evaporation Pb-Pb analysis. BSE images of zircons from the granodiorite (01RC183) show fine oscillatory (magmatic) zonation. Inherited cores were clearly present in the population, and several of the zircons showed etched and slightly embayed crystal faces, indicating a post-intrusive resorption event. Overgrowth rims with oscillatory zonation are evidence of later magmatic growth during the diorite intrusion. Twelve filaments were loaded with zircons: six with large single crystals and six with between three and six smaller crystals of similar size and morphology. A total of 58 heating steps were collected, of which 43 gave age errors of <10 Ma and were used in further age calculations. The data give an age plateau with a well-defined upper boundary at 495 +/- 2 Ma and a lower boundary of 489 +/- 7 Ma. Heating steps within the age plateau give a mean age of 493 +/- 1 Ma (2sigma). In order to review and refine the 207Pb/206Pb zircon evaporation results, U-Pb data were also collected from titanites (and feldspars, as a means of making accurate common Pb corrections) from the granodiorite (sample 01RC183). The 206Pb/238U and 207Pb/235U ages and both the two-point 238U/204Pb-206Pb/204Pb and 235U/204Pb-207Pb/204Pb isochron values yield ages in the range 490.5 +/- 0.6 Ma to 491.8 +/- 1.8 Ma. The concordia age was 490.5 +/- 2 Ma, and 207Pb/206Pb age was 493 +/- 14 Ma. These results are completely compatible with the evaporation results and suggest a weighted average U-Pb age of 492 +/- 1.5 Ma. |
| earth_materials | Y |
| structural_measurements | None |
| inorganic_geochemistry | None |
| organic_geochemistry | None |
| geochronology | None |
| isotope_groups | None |
| hydrochemistry | None |
| rock_properties | None |
| mineralogy | None |
| thin_sections | None |
| repository_samples | None |
| mineral_deposit_samples | None |
| mineral_deposit_waste_samples | None |
| linked_files | None |
| other_geological_data | None |
| project_name | EFTF - Isotopic Atlas of Australia |
| gda94_longitude | 139.2173552 |
| gda94_latitude | -34.9295907 |
| sample_originator | Foden, J.D. |
| date_acquired | 2000-01-01 00:00:00 |
| Links |
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