Paleozoic interarc basin in eastern Australia and a modern New Zealand analogue

Abstract

Abstract An analogue approach to the geology of the middle Paleozoic Hill End Trough of New South Wales suggests a close parallel between its latest Silurian-Early Devonian (Pridoli-Siegenian) configuration and that of the southern apex of the Havre Trough where it impinges on the North Island of New Zealand, that is, at the junction of a largely intraoceanic multiple arc system and a continental block. This analogy, rather than one with the interarc basins of wholly intraoceanic multiple arc systems adopted by other authors, is favoured by: dimensional comparability, the basinaxial location of silicic lava flows, the silica-intermediate to silica-rich character of magmatic products within and around the basin apex, the broad continental magmatic province immediately beyond the basin apex, the probable substantial epiclastic component of the basin fill, the probable lack of a truly oceanic basement to the basin fill, and by metallogenetic parallels. If the analogy is valid, then the Hill End Trough was, a...