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  • This dataset contains underlying data and results of 3D gas hydrate modelling at the southern Hikurangi Margin using PetroMod™ software and accompanies a manuscript published in the Geochemistry Geophysics Geosystems journal (DOI10.1029/2019GC008275). The model integrates thermal and microbial gas generation, migration and hydrate formation. Modelling these processes has improved the understanding of factors controlling hydrate distribution. Three spatial trends of concentrated hydrate occurrence are predicted. The first trend (I) is aligned with the principal deformation front in the overriding Australian plate. Concentrated hydrate deposits are predicted at or near the apexes of anticlines and to be mainly sourced from focussed migration and recycling of microbial gas generated beneath the hydrate stability zone. A second predicted trend (II) is related to deformation in the subducting Pacific plate associated with former Mesozoic subduction beneath Gondwana and the modern Pacific-Australian plate boundary. This trend is enhanced by increased advection of thermogenic gas through permeable layers in the subducting plate and focussed migration into the Neogene basin fill above Cretaceous‒Paleogene structures. The third trend (III) follows the northern margin of the Hikurangi Channel and is related to the presence of buried strata of the Hikurangi Channel system.

  • Supplementary Data Table 1 Otago and Marlborough schist, detrital zircon ages of schist protoliths U-Th-Pb isotopic ratios, measured and common-Pb corrected detrital zircon ages A) Western Otago: Samples 1-18 B) Marlborough: Samples 19-30 Supplementary Data Table 2 U-Pb zircon age data, southern New England Orogen granite suites: Samples 1-6 Key Points • Original protoliths are recognisable within the Haast Schist of New Zealand on the basis of distinctive detrital zircon age patterns. • The Aspiring Lithological Association (Otago Schist) of western Otago, is correlated with a similar belt of schistose rocks (Marlborough Schist) in western Marlborough, and both are assigned to a Waipapa Composite Terrane protolith of Jurassic to Late Triassic age. • The Jurassic-Late Triassic sandstones within Waipapa Composite Terrane are dominantly of granitoid provenance in eastern Australia. • Detrital zircons of Carboniferous age in Waipapa Composite Terrane support a possible New England Orogen provenance in northeastern NSW and southeastern Queensland, and also indicate possible primary sources for the gold and tungsten in the western Otago Schist and western Marlborough Schist. • This result is in marked contrast to eastern Otago Schist where the protolith is Rakaia Terrane of Late Triassic age and whose provenance is in central-eastern Queensland.