Torresan, M.E., and Gardner, J.V.,2000, Acoustic Mapping of the Regional Seafloor Geology in and Around Hawaiian Ocean Dredged-Material Disposal Sites, U.S. Geological Survey Open-file Report 00-124.

The backscatter data from the southwest margin between Makahu'ena Point and Port Allen shows that the debris avalanche blocks and associated deposits are characterized by high backscatter. The debris avalanche deposits form three high-backscatter features about 10 km long by 4 km wide each that trend nearly north-south in the central portion of the southwest flank. The remainder of the image surrounding the avalanche debris is characterized by a complex, high-backscatter, dendritic pattern. These high-backscatter dendritic features probably represent pathways (gullies, chutes, or canyons) for downslope sediment transport.

Backscatter data from the southeast margin of Kaua'i between Makahu'ena Point and Nawiliwili shows that the steep seaward edge of the submerged terrace is incised with high-backscatter gullies and canyons that coalesce downslope into broad, high-backscatter deposits. The broad areas of high backscatter on the lower slope correspond to the broader, smooth, lower-slope sediment mantle visible in the shaded-relief map.

go to a larger version of Figure 3 (3.3MB)
go to metadata for this field activity, A-1-98-HW

Top of page Beginning of OFR 00-124 URL: http://geopubs.wr.usgs.gov/open-file/of00-124/fig3.html Maintainer: Susan A. Cochran Last modified: 12 Dec 2000 U.S. Department of the Interior, U.S. Geological Survey, Western Region Coastal and Marine Geology