Sealers Bay submarine fan complex, Oligocene, southern New Zealand

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Abstract
The Oligocene Balleny Group of Chalky Island, southwestern Fiordland, comprises a typical continental margin sequence 900 m in thickness. Thin nearshore traction deposited sediments at the base are overlain by submarine canyon and fan lithofacies that were deposited by the full range of subaqueous mass‐transport processes. A steep‐walled channel within Balleny Group is interpreted as a fossil proximal fan‐channel. The sedimentary fill of the channel is texturally similar to sediments moving by slump‐creep in Recent submarine canyons and fan‐valleys. The field data presented indicate (1) that a small canyon complex at Sealers Bay was initially cut by subaqueous debris‐flows derived from an adjacent cliffed continental coast; (2) that transport within the upper parts of the canyon and fanchannel complex was primarily by inertia‐flow and slump‐creep; and (3) that these more proximal types of mass‐transport gave way gradationally and successively to fluxoturbidity and turbidity currents at locations further down‐slope, with consequent deposition of sediment in more distal fan‐channel and fan‐surface environments as fluxoturbidites and turbidites, with lesser contributions from inertia‐flows.