2678683
Persistent Identifier: https://pid.geoscience.gov.au/sample/AU2678683
| Property | Value |
|---|---|
| id | 2678683 |
| igsn | 10273/AU2678683 |
| sample_id | BB5674 |
| eno | 625703 |
| sampling_feature_name | BB5674 |
| sampling_feature_type | field site |
| sample_type | outcrop specimen |
| sampling_method | outcrop sampling |
| material_class | rock |
| stratigraphic_unit | Kurbayia Metamorphic Complex |
| geological_province | Kalkadoon-Leichhardt Domain |
| sample_remark | This unit is well exposed, and BB5674 was collected from an area of large boulders and pavements on the SE slope of hill. This meta-granodiorite is extensively recrystallised, with relict quartz, biotite, and feldspar grains. It is foliated, but not as gneissic as outcrops examined elsewhere. It hosts scattered mafic inclusions, and is cut by thin (up to ~30 cm) dykes of fine- to medium-grained leucogranite. In thin section, this rock is a deformed and metamorphosed fine- to medium-grained biotite granodiorite [average ~1.5 mm; ranging from ~0.3 mm (recrystallised quartz) to ~3 mm (relict feldspars)], though a gneissic texture is not obvious. Modal proportions are ~37% plagioclase, ~22% K-feldspar, ~25% quartz, ~15% biotite. K-feldspar is unaltered microcline microperthite. Plagioclase is generally slightly to moderately altered to sericite and/or muscovite, and epidote is associated, although it is not clear whether epidote is an alteration product or inclusions. Quartz grains are recrystallised to aggregates of smaller grains with boundaries ranging from straight to highly intricate. Polygonal grains are quite common. Biotite too is relatively common, and generally occurs as aggregates of several grains. It is extensively recrystallised, tends to be concentrated in irregular lenticles (not well developed), and hosts sparse tiny inclusions of zircon (pleochroic haloes) and apatite. Epidote is minor but widespread as well-formed euhedral-subhedral grains, commonly associated with biotite and plagioclase, and possibly of magmatic origin. Some have cores of altered allanite. Small euhedral-subhedral grains are common in some plagioclase grains, and some of these inclusions also display cores of altered allanite. This rock also contains traces of primary titanite (pleochroic from pale brown to red-brown), and myrmekite. |
| 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 | 139.632878 |
| gda94_latitude | -20.924295 |
| sample_originator | Bultitude, R.J. |
| date_acquired | None |
| Links |
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