The nature of fluids associated with the subvolcanic alkaline magmas and their role in 'hi-tech' metal transport and mineralization ...

• Main Author: Sokol, Krzysztof
• Format: Text
• Language: English
• Published: The University of St Andrews 2023
• Subjects: Energy transition; Alkaline magmas; Fenitization; High-field-strength elements; Rare metals; Ore deposits; Mineral chemistry; Greenland; Late-stage fluids; Stable isotopes; Major and trace element chemistry; Geochronology; Fluid inclusions; QE462.A4S7; Alkalic igneous rocks; Nonferrous metals; Mineralogical chemistry; Illerfissalik; Wall Rocks
• Online Access: https://dx.doi.org/10.17630/sta/493; https://research-repository.st-andrews.ac.uk/handle/10023/27744

Alkaline igneous rocks host many High Field Strength (HFSE) and Rare Earth Element (REE) deposits, which are key for the global low-carbon energy transition. To better target these, a better understanding of alteration associated with silicate-related ore deposits is required. Fluid-rock interaction around syenite forms altered haloes (’fenite’), normally uneconomic, but hosting many of the normally immobile HFSE expelled from the magmatic hearth. The fluid parameters which control the transport and deposition of these elements in the crust, their composition and the element speciation within need to be better constrained. Here a field study of an exceptionally exposed fenite (Gardar Province, SW Greenland) was followed by major and trace element, and stable isotope (O-H-S) analyses of whole rocks and minerals, and the investigation of fluid inclusion assemblages. The field data show the volcano-sedimentary wall-rocks to the west of Illerfissalik centre were altered by the ejection of metasomatic fluids. ...