Drowned reefs as indicators of the rate of subsidence of the Island of Hawaii
A major submerged terrace whose seaward edge is at about 150 m depth was investigated in 1983 during 10 dives with the Hawaii Undersea Research Laboratory (HURL) submersible Makali'i off Kealakekua Bay, Hawaii. The seaward termination of the terrace is a steep wall of reef limestone that extends from 150 to 250 m below sea level. Three samples of limestone collected from the reef face at depths of 204-219 m yield a weighted average age of 13,250 (S.D. 380) years before present. The -150 m terrace as well as two deeper terraces off northwestern Hawaii at depths of and apparently were formed by the interaction of glacioeustatic sea-level changes and island subsidence. The best fit of depth, age, and subsidence data indicates that the northwestern coast of Hawaii has subsided at an absolute rate of 1.8 to 3 + mm/yr and that the rate of subsidence has generally increased over the past 0.3 m.y. Each reef terrace grew intermittently for nearly 0.1 m.y.; the -150 m reef terrace was drowned about 13,000 years ago, the -390 m terrace about 145,000 years ago, and the -580 m terrace about 255,000 years ago. Warping of the two older terraces may have resulted from crustal loading caused by the major growth period of Mauna Loa volcano.
Citation Information
Publication Year | 1984 |
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Title | Drowned reefs as indicators of the rate of subsidence of the Island of Hawaii |
DOI | 10.1086/628910 |
Authors | J. G. Moore, D.J. Fornari |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Journal of Geology |
Index ID | 70013610 |
Record Source | USGS Publications Warehouse |