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TitleMetallogeny and its link to orogenic style during the Nuna supercontinent cycle
AuthorPehrsson, S P; Eglington, B E; Evans, D A D; Huston, D A; Reddy, S D
SourceGeological Society, Special Publication vol. 424, 2015 p. 83-94,
Alt SeriesEarth Sciences Sector, Contribution Series 20130034
PublisherGeological Society of London
Mediapaper; on-line; digital
File formatpdf
Subjectsmineral deposits; orogenesis; orogenic regions; modelling; geological history; development history; thermal history; mineral exploration; Nuna supercontinent
Illustrationslocation maps; graphs
ProgramGEM: Geo-mapping for Energy and Minerals Iron-oxide Copper-gold (IOCG) / Multiple Metals - Great Bear Lake (NWT)
Released2015 06 04
AbstractThe link between observed episodicity in ore deposit formation and preservation and the supercontinent cycle is well established, but this general framework has not, however, been able to explain a lack of deposits associated with some accretionary orogens during specific periods of Earth history. Here we show that there are intriguing correlations between styles of orogenesis and specific mineral deposit types, in the context of the Nuna supercontinent cycle. Using animated global reconstructions of Nuna's assembly and initial breakup, and integrating extensive databases of mineral deposits, stratigraphy, geochronology and palaeomagnetism we are able to assess spatial patterns of deposit formation and preservation. We find that lode gold, volcanic-hosted-massive-sulphide and nickel - copper deposits peak during closure of Nuna's interior ocean but decline during subsequent peripheral orogenesis, suggesting that accretionary style is also important. Deposits such as intrusion-related gold, carbonate-hosted lead-zinc and unconformity uranium deposits are associated with the post-assembly, peripheral orogenic phase. These observations imply that the use of plate reconstructions to assess orogenic style, although challenging for the Precambrian, can be a powerful tool for mineral exploration targeting.
Summary(Plain Language Summary, not published)
This paper presents the first ever animated model for the formation of Earth's first supercontinent, nearly 1.9 billion years ago. The model uses a GIS-based platform along with magnetic signatures of ancient rocks, ages of mountain belts and magmatic rocks and types of mineral deposits formed in distinctive settings to build a viable model for the period 2.1-1.4 billion years ago. The model suggests that the supercontinent was only fully together at about 1.5 billion years ago and that some classes of mineral deposits may have formed only at certain latitudes or in specific tectonic settings.

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