Environmental controls on B/Ca in calcite tests of the tropical planktic foraminifer species Globigerinoides ruber and Globigerinoides sacculifer

Environmental controls on B/Ca in calcite tests of the tropical planktic foraminifer species Globigerinoides ruber and Globigerinoides sacculifer

The ratio of boron to calcium (B/Ca) in the calcite tests of planktic foraminifers may serve as a proxy for past seawater chemistry, but controls on B incorporation are not yet certain. Here we present the results of laboratory culture experiments with live specimens of Globigerinoides ruber (pink) and Globigerinoides sacculifer, which provide new insight into B incorporation controls. We find ...

Intraspecific stable isotope variability in the planktic foraminifera Globigerinoides sacculifer: Results from laboratory experiments

Laboratory experiments conducted on the multichambered planktic foraminifera Globigerinoides sacculifer are used to determine the effect of symbiont photosynthesis on shell carbon and oxygen isotopic composition. Stable isotope analyses of individual chambers secreted under controlled temperature and light levels show that chamber jl3C values increase with increasing light levels. The effect of...

Evaluation of the biogeochemical controls on B/Ca of Globigerinoides ruber white from the Oceanic Flux Program, Bermuda

Millennial- to century-scale variability in Gulf of Mexico Holocene climate records

[1] Proxy records from two piston cores in the Gulf of Mexico (GOM) provide a detailed (50–100 year resolution) record of climate variability over the last 14,000 years. Long-term (millennial-scale) trends and changes are related to the transition from glacial to interglacial conditions and movement of the average position of the Intertropical Convergence Zone (ITCZ) related to orbital forcing....

the washback effect of discretepoint vs. integrative tests on the retention of content in knowledge tests

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