GLORIA mosaic of the U. S. Hawaiian exclusive economic zone

Conference · Fri Jun 01 04:00:00 EDT 1990 · AAPG Bulletin (American Association of Petroleum Geologists); (USA)

OSTI ID:6356859

Torresan, M E ^[1]

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1. Geological Survey, Menlo Park, CA (USA)

Digital long-range side-scan sonar reconnaissance surveys using GLORIA have imaged about 65% of the nearly 2.4 million km{sup 2} of the Hawaiian EEZ. The images have been processed and compiled into one mosaic that comprises the EEZ area surrounding the principal Hawaiian islands (from Hawaii to Kauai); extending on the south side of the ridge west to Kure Island, and on the north side to St. Rogatien Bank. The GLORIA images depict a variety of features that include enormous slumps and debris avalanches, lava flows, seafloor spreading fabric, fracture zones, seamounts, and unusual sedimentation patterns with more detail than previously had been possible with typical seismic reflection techniques. Some of these features were unknown before the GLORIA surveys. In particular, the GLORIA images show that the major degradational processes that affect the island and ridge areas are massive, likely tsunamogenic, blocky debris avalanches and slumps. These failures mantle the flanks of the ridge; some extending across the trough and up on to the Hawaiian Arch (up to 230 km from their sources). Over 30 failures are identified, ranging in area from 250 to > 6,000 km{sup 2} and having volumes from 500 to > 5,000 km{sup 3}. Such deposits cover > 125,000 km{sup 3} of the Ridge and adjacent seafloor. Also imaged are large Cenozoic submarine volcanic flow fields situated on the Hawaiian Arch. One such field, the North Arch field, is located north of Oahu between the Molokai and Murray fracture zones, and covers about 200,000 km{sup 2}. Prior to the GLORIA imagery only a small portion of this flow field was mapped. In addition, the imagery depicts the finer details of the Molokai and Murray fracture zones, the Cretaceous seafloor spreading fabric, and tensional faults on the Hawaiian Arch.

• OSTI ID: 6356859
• Report Number(s): CONF-900702--
• Conference Information: Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (USA) Journal Volume: 74:6
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
CRETACEOUS PERIOD
FEDERAL REGION IX
GEOLOGIC AGES
GEOLOGIC FAULTS
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
GEOPHYSICAL SURVEYS
HAWAII
IGNEOUS ROCKS
MEASURING INSTRUMENTS
MESOZOIC ERA
NORTH AMERICA
OFFSHORE SITES
RANGE FINDERS
ROCKS
SEA-FLOOR SPREADING
SEDIMENTATION
SEISMIC SURVEYS
SONAR
SURVEYS
TECTONICS
USA
VOLCANIC ROCKS