- Usage in publication:
-
- Lualualei Member*
- Modifications:
-
- Named
- Dominant lithology:
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- Basalt
- AAPG geologic province:
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- Oahu
Summary:
Named for exposures surrounding valley of Lualualei. Is oldest member of Waianae Volcanics, Waianae Range, Island of Oahu. Type section at Puu Heleakala [21 deg 24' 19"N, 158 deg 08' 06"W, Schofield Barracks 7.5' quad] Includes part of lower member and lowermost part of middle member of Waianae Volcanic Series (Stearns, IN Stearns and Vaksvik, 1935). Is 450 m thick on south side of Lualualei valley and present in drill cores 400 m below sea level. Lower contact not exposed. Composed of tholeiitic basalt. Contains fewer plagioclase-phyric lava flows and ash beds than Kamaileunu Member (new). Grades upward into Kamaileunu Member (new) of Waianae Volcanics. Is in fault contact with overlying Kamaileunu Member NNE of Puu Heleakala. Unconformably underlies Quaternary sedimentary deposits. K-Ar ages range from 3.8 to 3.0 Ma (McDougall, 1964; Doell and Dalrymple, 1973). Age is Pliocene.
Source: GNU records (USGS DDS-6; Menlo GNULEX).
For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.
Asterisk (*) indicates published by U.S. Geological Survey authors.
"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).
Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).