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The Maniitsoq project is supported by the Ministry of Mineral Resources, Government of Greenland. NJG and PAC thank Australian Research Council grant FL160100168 for financial support. ON is supported by Australian Research Council grant FT140101062 and the Melbourne TIE team. ; Archean cratons are composites of terranes formed at different times, juxtaposed during craton assembly. Cratons are underpinned by a deep lithospheric root, and models for the development of this cratonic lithosphere include both vertical and horizontal accretion. How different Archean terranes at the surface are reflected vertically within the lithosphere, which might inform on modes of formation, is poorly constrained. Kimberlites, which originate from significant depths within the upper mantle, sample cratonic interiors. The North Atlantic Craton, West Greenland, comprises Eoarchean and Mesoarchean gneiss terranes – the latter including the Akia Terrane – assembled during the late Archean. We report U–Pb and Hf isotopic, and trace element, data measured in zircon xenocrysts from a Neoproterozoic (557 Ma) kimberlite which intruded the Mesoarchean Akia Terrane. The zircon trace element profiles suggest they crystallized from evolved magmas, and their Eo- to Neoarchean U–Pb ages match the surrounding gneiss terranes, and highlight that magmatism was episodic. Zircon Hf isotope values lie within two crustal evolution trends: a Mesoarchean trend and an Eoarchean trend. The Eoarchean trend is anchored on 3.8 Ga orthogneiss, and includes 3.6–3.5 Ga, 2.7 and 2.5–2.4 Ga aged zircons. The Mesoarchean Akia Terrane may have been built upon mafic crust, in which case all zircons whose Hf isotopes lie within the Eoarchean trend were derived from the surrounding Eoarchean gneiss terranes, emplaced under the Akia Terrane after ca. 2.97 or 2.7 Ga, perhaps during late Archean terrane assembly. Kimberlite-hosted peridotite rhenium depletion model ages suggest a late Archean stabilization for the lithospheric mantle. The zircon data support a model of lithospheric growth via tectonic stacking for the North Atlantic Craton. ; Publisher PDF ; Peer reviewed

Myanmar is perhaps one of the world's most prospective but least explored minerals jurisdictions, containing important known deposits of tin, tungsten, copper, gold, zinc, lead, nickel, silver, jade and gemstones. A scarcity of recent geological mapping available in published form, coupled with an unfavourable political climate, has resulted in the fact that, although characterized by several world-class deposits, the nation's mineral resource sector is underdeveloped. As well as representing a potential new search space for a range of commodities, many of Myanmar's known existing mineral deposits remain highly prospective. Myanmar lies at a crucial geologic juncture, immediately south of the Eastern Himalayan Syntaxis, however it remains geologically enigmatic. Its Mesozoic- Recent geological history is dominated by several orogenic events representing the closing of the Tethys Ocean. We present new zircon U-Pb age data related to several styles of mineralization within Myanmar. We outline a tectonic model for Myanmar from the Late Cretaceous onwards, and document nine major mineralization styles representing a range of commodities found within the country. We propose a metallogenetic model that places the genesis of many of these metallotects within the framework of the subduction and suturing of Neo- Tethys and the subsequent Himalayan Orogeny. Temporal overlap of favourable conditions for the formation of particular deposit types during orogenic progression permits the genesis of differing metallotects during the same orogenic event. We suggest the evolution of these favourable conditions and resulting genesis of much of Myanmar's mineral deposits, represents a single, evolving, mineral system: the subduction and suturing of Neo-Tethys.