Publications

The Aure Trough is located over the suture between the once-allochthonous eastern Papua composite terrane (EPCT): which underlies most of the modern Papuan Peninsula, and the Australian craton. The Aure Trough is the southeastward continuation of the hydrocarbon-productive Papuan basin. Stratigraphic and tectonic relationships indicate docking of the EPCT in the Oligocene. Discontinuous outcroppings of basin strata occur along the southwest margin of the Papuan Peninsula. Oligocene-early Miocene units there mostly consist of resedimented carbonate debris with some volcaniclastics (Dokuna Tuff and Bootless Inlet, Boera, and Fairfax Formations). Strata indicate general highstand conditions in the basin immediately following collision. Thick, extensive, mostly deep-marine clastics were deposited in the basin in the middle Miocene-Pliocene. Increased clastics in the middle Miocene (lower Chiria Formation) record uplift of the docked EPCT possibly due to post-collisional isostatic rebound. Sediment was eroded from a mixed metamorphic-sedimentary provenance during the early middle Miocene. Younger clastics in middle Miocene to Pliocene strata (upper Chiria, Talama, Lavao, Orubadi, and Era Formations) were derived mostly from a volcanic arc, and record beginning of southward subduction beneath the northern edge of the New Guinea orogen. In addition, stratigraphic evidence of local faulting and repeated alternations between clastic and carbonate facies from the middle Miocene upward reflect local deformation and relative sea level changes with continued tectonic shortening. Local deformation likely was part of overthrusting of the Papuan Peninsula onto the craton margin. Tectonism ultimately resulted in formation of the Aure fold and thrust belt in the Pliocene. Pliocene deformation probably was a far-field response to collision of the Bismarck-New Britain volcanic arc with the northern edge of New Guinea.