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Crustal subsidence rate off Hawaii determined from 234U/238U ages of drowned coral reefs

K.R. Ludwig·Barney J. Szabo·J.G. Moore·K. R. Simmons
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Abstract

A series of submerged coral reefs off northwestern Hawaii was formed during (largely glacial) intervals when the rate of local sea-level rise was less than the maximum upward growth rate of the reefs. Mass-spectrometric 234 U/ 238 U ages for samples from six such reefs range from 17 to 475 ka and indicate that this part of the Hawaiian Ridge has been subsiding at a roughly uniform rate of 2.6 mm/yr for the past 475 ka. The 234 U/ 238 U ages are in general agreement with model ages of reef drowning (based on estimates of paleo-sea-level stands derived from oxygen-isotope ratios of deep-sea sediments), but there are disagreements in detail. The high attainable precision (±10 ka or better on samples younger than ∼800 ka), large applicable age range, relative robustness against open-system behavior, and ease of analysis for this technique hold great promise for future applications of dating of 50-1000 ka coral.

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GeologyArticle
90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 16.341225619207496° to 25.005972656239187° latitude; -161.6748046875° to -152.9296875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeXRIS

K.R. Ludwig, Barney J. Szabo, J.G. Moore, K. R. Simmons. 1991. Crustal subsidence rate off Hawaii determined from 234U/238U ages of drowned coral reefs. https://doi.org/10.1130/0091-7613(1991)019%3C0171%3Acsrohd%3E2.3.co%3B2

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