Submarine features of modern open-sea fan deltas, Huon Peninsula, Papua New Guinea
Abstract
A series of fan deltas has been delineated in water depths between 300 and 1900 m along the 75 km shelf and slope of the northern Huon Gulf, Papua New Guinea using the HAWAII MR1 side-scan system. Comparison of these fan deltas suggests that submarine slope profiles and feeder systems (i.e., type and size) are the most important factors controlling the construction and the geometry of the submarine fan deltas. Fan deltas are fully developed only at large rivers in areas with a SS-shaped slope profile.
Six zones are recognised on the SS-profiled fan delta surface based on the submarine topographic characteristics, dominant acoustic facies and slopes. The zonation differs from that of Prior and Bornhold (1989) from fan deltas in a British Columbian fjord in terms of magnitude, slope profiles and submarine channelling patterns. The Huon fan deltas represent larger, more dynamic, deep-water delta systems with individual fan deltas up to 200 km2. The main parts of the Huon fan deltas are deposited below 500 m, 5 km from river mouths. Large quantities of coarse-grained sediments are found in water depths over 1400 m, 13 km from river mouths. The relief of the interfingered narrow ridges and gullies in Zone 3 is up to 100 m. Zone 6 has a slope gradient of 4.4°, much steeper than Zone 5 (1.5°).
The Huon fan deltas can not be easily fitted into any of the existing classification. They warrant a comparative study of fan deltas with similar feeder systems but different slope profiles, and with similar slope profiles but different feeder systems in the same basin regime. Delta classification and nomenclature needs to reflect seven attributes: feeder system, basin dynamics, water depth (depth ratio), slope profile, dominant slope process, delta-front grain size and geometry.
Department
Center for Coastal and Ocean Mapping
Publication Date
8-1-1995
Journal Title
Sedimentary Geology
Publisher
Elsevier
Digital Object Identifier (DOI)
Document Type
Article
Recommended Citation
Liu,K, Crook, K.A.W., Hughes Clarke,J.E. amd Whitmore,G.P., 1995, Submarine features of modern open-sea fan deltas, Huon Peninsula, Papua New Guinea: Sedimentary Geology, v.98, p.63-77.