A 28 000 year record of hydrography in the anoxic Cariaco Basin (Venezuela) based on oxygen isotope data from multiple species of planktonic foraminifera

Lin Hui-Ling Lin, L. C. Peterson

Research output: Contribution to journalArticle


During the last glacial, the reduced offset between the δ18O values of two foram species as compared to the Holocene suggests a decreased thermal gradient in the upper water column resulting from a combination of surface cooling and the effects of a shallower glacial sill depth. Between 12 600 and 9500 years ago, the convergence of δ18O between G. bulloides and N. dutertrei supports intensified vertical mixing and is consistent with the strong upwelling indicated by high abundances of G. bulloides and biogenic opal content. The similar timing of negative δ18O excursions in G. ruber records and periods of maximum meltwater discharge during the deglaciation suggests that surface waters over the basin are influenced by the return of meltwater to the ocean reservoir. The mid-Holocene "hypsithermal' around 6000 years BP is recorded by a broad interval of depleted δ18O values in pink G. ruber. -from Authors

Original languageEnglish (US)
Pages (from-to)425-442
Number of pages18
JournalJournal - Geological Society of China
Issue number4
StatePublished - Jan 1 1994


ASJC Scopus subject areas

  • Geology

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