{ "type":"Feature", "geometry":{ "type":"Point", "coordinates":[ 141.62446, -33.49948, 68.50718 ] }, "properties":{ "igsn":"10.60494/03dt-x152", "sample_id":"2023330042", "eno":867077, "sampling_feature_name":"NDIWMP02", "sampling_feature_type":"borehole", "sample_type":"half core", "sampling_method":"core drilling", "material_class":"rock", "stratigraphic_unit":null, "geological_province":"Delamerian Orogen", "sample_remark":"Mole et al. (2024): Drillhole NDIWMP02 samples a prominent NE-trending magnetic lineament. Magmatic units in this hole are magnetic and are probably the cause of the magnetic anomaly. The sedimentary rocks towards the bottom of the hole are less magnetic. This hole was drilled using a conventional diamond drill-rig, reached a total depth of 646.3 m, and recovered about 100 m of diamond core. The primary lithologies in the hole are (1) an intermediate porphyritic intrusion (represented by samples 9652125/2023330042 and 9652129/2023330043), which occurs above a (2) fine- to medium-grained siliciclastic unit (represented by sample 9652132/2023330034). Contact between both units occurs across ~10 cm and is altered and fractured, making the primary nature of the contact unclear. The porphyritic unit varies subtly between a more aphanitic and aphyric phase (represented by sample 9652129/2023330043) and a more porphyritic phase (represented by current sample 9652125/2023330042), although there is no clear boundary. In terms of alteration, the entire core, including the siliciclastic rock, is variably altered (mostly pinkish hematite staining of albite, with some lighter-coloured alteration (sericite?) surrounding fractures and veins). Zoned plagioclase phenocrysts within the porphyry are commonly altered to a pale greenish colour. Sample 9652125/2023330042 was taken from the more porphyritic phase of the rhyo-dacite porphyry. The sample taken yielded pXRF Zr contents of 720-447 ppm. The sample was taken from a relatively homogeneous, dark grey interval. In thin section, sample 9652125/2023330042 is a strongly recrystallised, fine-grained moderately feldspar-phyric, spherulitic amphibole-biotite-bearing granophyric high-level intrusive or rhyolitic lava of I-type affinity. The overall texture involves abundant spherulites, with ~10% feldspar, quartz and ferromagnesian phenocrysts surrounded by a completely recrystallised polygonal quartz-feldspar-rich groundmass. Spherulitic, radial micropoikilitic to granophyric grains are 0.3-0.6 mm and comprise radiating granophyric intergrowths of K-feldspar, quartz and lesser fine plates of biotite. Most radial features appear to have no central mineral phase, with only rare fine quartz phenocrysts present at centres of some grains. Plagioclase and K-feldspar are the main phenocryst phases, occurring as stout tabular to equant grains 0.6-2.4 mm in size. All feldspars are pervasively sericite-altered and recrystallised with irregular boundaries against the recrystallised polygonal groundmass. Quartz is an uncommon phenocryst phase occurring as rare anhedral, often recrystallised grains up to 0.4 mm. Ferromagnesian phenocrysts are completely recrystallised to decussate masses of deep blue-green actinolite and deep red-brown to straw biotite. The amphibole and biotite clusters are mutually exclusive, consistent with replacement of both primary biotite and amphibole phenocrysts. There is no distinctive habit with most replacements forming irregular flattened masses that may be aligned parallel to a weak flow foliation. Accessory phases include equant magnetite often surrounded by decussate biotite, prismatic zircon and stout tabular apatite associated with decussate biotite masses. The spherulitic textures are consistent with a very high-level subvolcanic intrusive or rhyolitic lava. Although the fine granophyric textures are preserved, ferromagnesian phases are completely recrystallised, along with the groundmass. There are no major signs of deformation and the secondary mineralogy is most consistent with recrystallisation under albite-epidote hornfels facies conditions. Recrystallisation was accompanied by pervasive sericitisation of feldspar phenocrysts and moderate albitisation.", "earth_materials":"Y", "structural_measurements":null, "inorganic_geochemistry":null, "organic_geochemistry":null, "geochronology":"Y", "isotope_groups":null, "hydrochemistry":null, "rock_properties":null, "mineralogy":null, "thin_sections":null, "repository_samples":"Y", "mineral_deposit_samples":null, "mineral_deposit_waste_samples":null, "linked_files":null, "other_geological_data":null, "project_name":"EFTF - Darling-Curnamona-Delamarian (DCD)", "gda94_longitude":141.62446, "gda94_latitude":-33.49948, "sample_originator":"Clark, A.", "date_acquired":"2023-11-26T00:00:00" }, "id":9652125, "prev":9652124, "next":9652128, "links":[ { "type":"application/json", "rel":"root", "title":"The landing page of this server as JSON", "href":"https://linkeddata.pid.geoscience.gov.au?f=json" }, { "type":"text/html", "rel":"root", "title":"The landing page of this server as HTML", "href":"https://linkeddata.pid.geoscience.gov.au?f=html" }, { "rel":"self", "type":"application/geo+json", "title":"This document as JSON", "href":"https://linkeddata.pid.geoscience.gov.au/collections/sp/items/9652125?f=json" }, { "rel":"alternate", "type":"application/ld+json", "title":"This document as RDF (JSON-LD)", "href":"https://linkeddata.pid.geoscience.gov.au/collections/sp/items/9652125?f=jsonld" }, { "rel":"alternate", "type":"text/html", "title":"This document as HTML", "href":"https://linkeddata.pid.geoscience.gov.au/collections/sp/items/9652125?f=html" }, { "rel":"collection", "type":"application/json", "title":"Sample", "href":"https://linkeddata.pid.geoscience.gov.au/collections/sp" }, { "rel":"prev", "type":"application/json", "href":"https://linkeddata.pid.geoscience.gov.au/collections/sp/items/9652124?f=json" }, { "rel":"next", "type":"application/json", "href":"https://linkeddata.pid.geoscience.gov.au/collections/sp/items/9652128?f=json" } ], "pid":"https://pid.geoscience.gov.au/sample/AU9652125" }