2678822
Persistent Identifier: https://pid.geoscience.gov.au/sample/AU2678822
| Property | Value |
|---|---|
| id | 2678822 |
| igsn | 10273/AU2678822 |
| sample_id | R2427070 |
| eno | 625741 |
| sampling_feature_name | CDP001 |
| sampling_feature_type | borehole |
| sample_type | core |
| sampling_method | core diamond |
| material_class | rock |
| stratigraphic_unit | Moodini Supersuite |
| geological_province | None |
| sample_remark | Medium-grained massive granitoid composed of moderately abundant pink K-feldspar, grey felsic grains, and minor randomly oriented dark flakes (biotite, muscovite). In thin section, this sample displays a massive hypidiomorphic granitoid texture, modified by weak selective alteration. Quartz (38%) forms anhedral 2-4 mm grains, commonly in granular aggregates. Most grains display weak undulose extinction and are laced by trace acicular rutile. K-feldspar (33%) forms randomly oriented subhedral prisms up to ~4 mm, commonly with simple twinning as well as tartan twinning. Plagioclase (20%) forms randomly oriented 0.5-2.0 mm prisms clouded by minute sericite flecks, minor tiny red hematite grains, and trace larger colourless muscovite flakes. Muscovite (4%) occurs as primary 0.5-2.0 mm plates either in close association with biotite, or discretely at contacts of felsic grains. Biotite (1%) forms 0.2-0.5 mm plates with straw yellow to dark brown pleochroism, but most are partially to completely replaced along cleavage by pleochroic green chlorite. Rare small purple fluorite grains occur in some biotite sites. Garnet is observed as a single ~4 mm euhedral crystal containing inclusions of anhedral quartz and trace small muscovite. Opaques form uncommon equant grains (?magnetite) associated with biotite and in quartz. Zircon occurs as rare tiny terminated prisms in K-feldspar. INTERPRETATION: This sample initially crystallised as a massive hypidiomorphic monzogranite of peraluminous character, composed of K-feldspar + quartz + plagioclase + accessories (muscovite, biotite, garnet, magnetite, zircon). During cooling, minor muscovite partially replaced plagioclase, and primary K-feldspar partially inverted to microcline. Circulation of a small amount of hydrous fluid generated minor new sericite + chlorite + hematite + fluorite partially replacing primary plagioclase and biotite. |
| earth_materials | Y |
| structural_measurements | None |
| inorganic_geochemistry | Y |
| organic_geochemistry | None |
| geochronology | Y |
| isotope_groups | Y |
| hydrochemistry | None |
| rock_properties | None |
| mineralogy | None |
| thin_sections | None |
| repository_samples | Y |
| mineral_deposit_samples | None |
| mineral_deposit_waste_samples | None |
| linked_files | None |
| other_geological_data | None |
| project_name | None |
| gda94_longitude | 129.256504 |
| gda94_latitude | -31.6376894 |
| sample_originator | Jagodzinski, E.A. |
| date_acquired | 2017-10-23 00:00:00 |
| Links |
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