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Here we present a practical workflow that can be applied to characterising and dating a variety of sedimentary rocks. The approach integrates multimodal mineralogical, petrological, and in-situ radioisotope characterisation. We utilise the Tescan Integrated Mineral Analyzer (TIMA) for automated, 2D quantitative mineralogical analysis of source and reservoir rocks including shale, sandstone, and carbonate. Subsequently, we integrate X-ray computed tomography (XCT) with TIMA to undertake multimodal, mineralogical and petrological characterisation of samples in order to build a 3D visualisation and volumetric reconstruction of mineralogical phases (and organics) and pore space. The resulting multimodal, 2D-3D XCT-TIMA mineralogy provides quantitative characterisation of sediments (from regional basin scale to local reservoir scale), and identifies appropriate mineral phases for in-situ laser ablation mass spectrometry geochronology (e.g., in-situ U-Pb dating of carbonate minerals, in-situ Rb-Sr dating of potassium-bearing minerals, and U-Pb and (U-Th)/He dating of siliciclastic sediments, etc.). The multi-technique workflow yields quantitative mineralogy and petrology of sediments and provides insights into their provenance, diagenesis, and burial history, with advantages over conventional methods in terms of sample consumption, time, cost, safety, and spatial resolution., Open-Access Online Publication: May 29, 2023

Supplementary Figure C: Mount map of 2022-IGO1, showing locations of xenotime with respect to ore mineralogy (including chalcocite). Note that not all xenotime was analyzed; the numbering system was initially chosen on low-resolution BSE images obtained with the TIMA, but high-resolution images revealed that many xenotime grains were below the analytical resolution. Two depth slices of 2022-IGO1 are shown, with the original depth also corresponding to the automated mineral analysis maps of the individual polished blocks in Supplementary Fig. A.

We describe a vision for a national-scale heavy mineral (HM) map generated through automated mineralogical identification and quantification of HMs contained in floodplain sediments from large catchments covering most of Australia. The composition of the sediments reflects the dominant rock types in each catchment, with the generally resistant HMs largely preserving the mineralogical fingerprint of their host protoliths through the weathering-transport-deposition cycle. Heavy mineral presence/absence, absolute and relative abundance, and co-occurrence are metrics useful to map, discover and interpret catchment lithotype(s), geodynamic setting, magmatism, metamorphic grade, alteration or mineralization. Underpinning this vision is a pilot project, focusing on a subset of the national sediment sample archive, which is used to demonstrate the feasibility of the larger, national-scale project. We preview a bespoke, cloud-based mineral network analysis (MNA) tool to visualize, explore and discover relationships between HMs as well as between them and geological setting or mineral deposits. We envisage that the Heavy Mineral Map of Australia and MNA tool will contribute significantly to mineral prospectivity analysis and modeling here, particularly for technology critical elements and their host minerals, which are central to the global economy transitioning to a more sustainable, decarbonized paradigm.

Summary Acquisition and analysis of geochemical data are pervasive in the Earth, environmental, and planetary sciences, but very little of it is FAIR (Findable, Accessible, Interoperable and Reusable). The need for global standards and best practices for geochemical data is increasingly urgent so that scientists can better share geochemical data in a global network of distributed databases. Although several efforts have been undertaken to standardise geochemical data for publication within the geoscience discipline, global standards and best practices for FAIR geochemical data are lacking: standard protocols for exchanging geochemical data among distributed data systems still need to be defined and approved by a global community. Discovery in many fields will benefit from a global geochemical data network, from the study of global climate change, to present and past biogeochemical cycles, to magmatic processes, to the origin and evolution of our solar system. There are many lessons that can be learned from the OneGeology project in building a global community and its approach to technical and organisational governance to help build OneGeochemistry: a global geochemical network. Introduction Geochemical data are pervasively used in the Earth, environmental and planetary sciences and are fundamental for understanding past, present, and future processes in natural systems, from the interior of the Earth to its surface environments on land, in the oceans, and in the air, to the entire solar system. Historically, accessibility and preservation of geochemical data has been sporadic and fragmented, though geochemical data systems such as EarthChem, PetDB, and GEOROC have had a revolutionary impact on data access and re-use in igneous petrology. In response to Open Access policies and science demands, new geochemical database systems are emerging at national, programmatic, and subdomain levels, but these activities are not coordinated and very little of the data is FAIR (Wilkinson et al., 2016). OneGeology, developed in 2007, created a global venture to increase the accessibility of geological map data, and following the lead of Google Earth, make it accessible over the internet using web services (Jackson, 2010; Jackson and Wyborn, 2008). We propose to follow OneGeology with an equivalent global initiative: OneGeochemistry. What is the Vision and Goal of OneGeochemistry? OneGeochemistry seeks to create a global geochemical data network that facilitates and promotes discovery and access of geochemical data through coordination and collaboration among international geochemical data providers. OneGeochemistry will establish a global network of research infrastructure and data providers to develop and implement best practices and interoperability standards for geochemical data that will enable machine-to-machine exchange and integration of geochemical data from all participating networks so that scientists world-wide can discover, explore, mine, and analyze geochemical data in new and innovative ways. What is required? OneGeochemistry is envisioned as a distributed architecture, where geochemical data are available globally using web services. The technology is not complex, but it does require that the international geochemistry community come together and agree on the standards (including vocabularies and ontologies) that will enable geochemical data from participating providers to be FAIR. Several efforts have been undertaken in the past to establish best practices for reporting geochemical data in publications within the geoscience discipline (e.g., Deines, 2003; Staudigel et al., 2003; Potts, 2012; Goldstein et al., 2014). However, as they are designed as best practices for data in publications, they do not support use in data processing and analysis, and are also limited in their capacity to interoperate with other disciplines. There has also been some development of data exchange protocols to allow data from multiple geochemical databases to be brought into a coherent entity (e.g., EarthChem XML, IEDA 2018), but these were intended for local use with a limited number of partner data systems and have not yet been endorsed as agreed international standards. Interoperability of geochemical data for use in machine-to-machine interactions and modern analytical techniques, such as machine learning and artificial intelligence, will require more comprehensive standards that also take into account uncertainties and provenance. As we will be aggregating multiple databases from multiple instruments we will need attributes on the sensors (instruments), running conditions, sample preparation, reduction and manipulation of raw data, reference material measurements and other aspects that often pertain only to a certain methodology. We will need a standard for each technique. We may also need to align as much as possible with standards from other disciplines and do this at an international level. For geochemistry, the actual geological material that is analysed for chemical properties can be described using the controlled and governed vocabularies developed by the International Union of Geological Sciences (e.g., CGI IUGS, 2016) or alternatively the Observation Data Model 2 (ODM2; Horsburgh, 2016), and identified using the global IGSN system (Lehnert et al. 2019a). Describing measured values of the elements of the periodic table and the procedures used will require liaison with the International Chemistry community. What are the barriers? The Geochemistry community has been slow to embrace the need for global standards that ensure the interchange and reuse of geochemical data, unlike the existing global networks that have matured for other earth and environmental science communities such as climate (e.g., Earth Systems Grid Federation (ESGF), Earth Observation (GEO), and geophysics (e.g., Federated Digital Seismic Network (FDSN)). The common factor for these successful communities is that their data volumes are substantial in comparison to geochemical data and therefore their collections are usually housed in specifically funded data centers, with specialized teams that are specifically funded to manage and archive the data to enable sharing, manipulation, reuse and repurposing of data in their repositories. In contrast, historically geochemical data is small in volume, poorly curated, rarely shared and integrated, and often stored locally on C-drives or at best, in institutional repositories so that they can support a few research publications. Communities do exist for the sharing and progress of the science of Geochemistry research (e.g., Geochemical Society, European Association of Geochemists): these now should extend to embrace the significant issues that relate to the standardisation and sharing of geochemical data. OneGeology mobilised geologists from all around the planet to share data across national boundaries and sectors (research, government and industry): One Geochemistry will also have to unite and mobilise geochemists to do likewise. As OneGeology showed, developing a governance model for the organisation, as well as ensuring organisational cohesion and agreement of required technical standards and vocabularies will be critical (Simons et al., 2014). A business model will also need to be developed to ensure long-term sustainability. Next steps Our most urgent task is to identify and engage relevant communities in the Earth sciences and beyond (Lehnert et al. 2019b). We need to bring together relevant networks such as large national and international science programs, observatories, and research infrastructure networks that generate geochemical data and engender a need to share data openly with the global community (e.g., European Plate Observing System (EPOS), AuScope, Critical Zone Exploration Network; NSF-USGS initiative SZ4D, IUGS Deep-time Digital Earth). We also need to include networks that develop, deploy, and operate data infrastructure (EarthCube, EarthChem, Astromaterials Data System) as well as international organizations that actively develop, govern, and promote data standards, best practices, and policies (e.g. Earth Science Information Partners (ESIP), Research Data Alliance, Open Geospatial Consortium (OGC)); professional societies, unions, and publishers who can advance implementation of best practices. Combined, we will work towards both the development of geochemical data standards as well as exploring ideas and opportunities for a global geochemical data network that facilitates and promotes discovery and access of geochemical data through coordination and collaboration among international geochemical data providers. Developing the appropriate governance and business models will be critical, and it goes without saying, funding will be essential. The first goal will be to converge on a common vision for OneGeochemistry: a global geochemical data network that will enable new avenues of scientific discoveries in fields ranging from the study of global climate change, to present and past biogeochemical cycles, to magmatic processes.

Simberi Island is an eroded Pliocene alkaline volcano, the oldest in the Pliocene to Holocene Tabar-Lihir-Tanga-Feni (TLTF) island arc. These islands are derived from partial melting of subduction-modified mantle at $>$60 km depth along extensional, pull-apart structures. Explosive volcanism has brought samples of the mantle wedge to the surface. Within these samples are sulphate-, carbonate-, hydrous-, alkali-rich aluminosilicate glasses which represent quenched slab-derived magmas (SCHARM). SCHARM reacts with mantle peridotite to create a vertically zoned mantle wedge consisting of phlogopite-clinopyroxenite at P $>$ 30 kbar and amphibole-clinopyroxenite at 21 to 30 kbar at 930-1080$\sp\circ$C. Metasomatism of the mantle wedge by SCHARM controls the mineralogical, chemical and isotopic composition of TLTF arc volcanics. The presence of sulphate within SCHARM indicates a high intrinsic oxygen fugacity of FMQ + 4. Oxidative metasomatism of the mantle wedge by SCHARM is responsible for high $\rm Fe\sb2O\sb3$/FeO ratios in the lavas, the early appearance of magnetite on the liquidus and the crystallization of a sulphate-bearing feldspathoidal mineral (ha uyne) in the TLTF lavas. Titanium depletion in the rocks of the TLTF arc is accounted for by the low initial solubility of Ti in SCHARM, coupled with the strong partitioning of Ti into phlogopite at high fo$\sb2.$ Enhanced solubility of sulphur in high fO$\sb2$ melts, caused destabilization of mantle sulfides and concomitant enrichment of chalcophile Au and Cu in volatile-rich, mantle-derived melts, and may be a significant factor in the development of volcanic-hosted Au-Cu deposits in the arc. Enrichments of large ion lithophile elements and rare-earth element in basanites and alkali basalts are also due to SCHARM contamination. Negative Ce and positive Eu anomalies in Simberi basalts are produced by partial melting of feldspathic minerals in subducted, seawater altered mid-ocean ridge basalt (MORB), at the basalt-eclogite transition zone in the mantle. Eutectic melting constraints indicate that SCHARM could be derived during the melting of scapolite, produced by prograde metamorphic reactions between MORB plagioclase and low temperature secondary minerals (calcite, gypsum) in the subducting slab. Metasomatic replacement of forsteritic olivine $\rm(\delta\sp O=5\perthous)$ by high $\rm\delta\sp O$ SCHARM produces $\sp $O-enriched sodian diopside and magnetite $\rm(\delta\sp O$ = 6.3-6.8$\perthous)$ in Simberi basanites. Isotopic disequilibrium exists because of the short 6 Ma) residence time of SCHARM in the mantle.