Rare earth elements in Foraminifera tests

Rare earth elements in Foraminifera tests

OLR (1985)32 (12) D. SubmarineGeologyand Geophysics 85:7127 West, R.G, et al., 1985. Causes of Cenozoic glaciation. J. geol. Soc., Lond., 142(3):413...

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OLR (1985)32 (12)

D. SubmarineGeologyand Geophysics

85:7127 West, R.G, et al., 1985. Causes of Cenozoic glaciation. J. geol. Soc., Lond., 142(3):413-500; 7 papers. This thematic set begins with a brief historical overview of key advances in the study of Quaternary climate change, followed by presentation of a framework for the Pleistocene glaciations and a review of Mesozoic climates. Other papers concern the last ice sheets of mid-latitudes, a seasonal climate model for Cenozoic glaciation, climate of the tropical Andes in the Plio-Pleistocene, and a long pollen record from southern Italy. School of Botany, Univ. of Cambridge, CB2 3EA, UK. (msg)

D 1 8 0 . Paleontology (see also E BIOLOGICAL OCEANOGRAPHY) 85:7128 Bukry, David (comment) and K.J. Hsti (reply), 1985. Numerical ages of Cenozoic biostratigraphic datum levels: results of South Atlantic Leg 73 drilling: discussion and reply. Geol. Soc. Am. Bull., 96(6):813-815. USGS, A-015, Scripps Inst. of Oceanogr., La Jolla, CA 92093, USA.

85:7129 Delaney, M.L., A.W.H. B6 and E.A. Boyle, 1985. Li, Sr, Mg, and Na in foraminiferal calcite shells from laboratory culture, sediment traps, and sediment cores. Geochirn. cosmochim. Acta, 49(6): 1327-1341. Experiments with Globigerinoides sacculifer suggest that the ratios of Li and Sr to Ca in the shells are a function of these ratios in the culture solutions. Mg/Ca and N a / C a in the shells did not vary with changes of these ratios in the culture solution. The Sr/Ca, Mg/Ca, and N a / C a ratios in the natural samples roughly correlate with calcification temperature, whereas differences in the Li/Ca ratios are small and not systematically related to temperature. However, laboratory culture experiments at 20°C and 30°C showed no variation in the Li/Ca, Sr/Ca, Mg/Ca, and N a / C a ratios with calcification temperature; observed differences in-situ may be due to some other environmental factor correlated with temperature. Center for Mar. Stud., Univ. of Calif., Santa Cruz, CA 95064, USA. 85:7130 Masuda, Fujio, 1984. How to understand the empirical relations between elemental content of skeletal marine carbonates and water temperature

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or salinity? A. Rept Inst. Geosci., Univ. Tsukuba, 10:96-101. An optimum temperature model for non-estuarine species is presented, in which calcium carbonate metabolism (determined by temperature) controls shell elemental content. Four types of empirical relationships previously observed between skeletal carbonate content and an environmental factor can be reconstructed using the model; an optimum condition is seen for each species. Inst. of Geosci., Univ. of Tsukuba, Japan. (gsb) 85:7131 Palmer, M.R., 1985. Rare earth elements in Foraminifera tests. Earth planet. Sci. Letts, 73(24):285-298. REE are present in three phases in Foraminifera tests collected from sea floor sediments; included in the foraminiferal calcite matrix (lattice REE), associated with an authigenic FeMn-rich phase adsorbed onto the surface of the test following the death of the organism (coating REE) and associated with alumino-silicate detritus (detrital REE). Approximately 90% of the REE measured in the non-detrital (lattice plus coating) phase resides in the coating phase. Dept. of Geol. and Geophys., Yale Univ., New Haven, CT 06511, USA. 85:7132 Palmer, M.R. and H. Elderfield, 1985. Variations in the Nd isotopic composition of Foraminifera from Atlantic Ocean sediments. Earth planet. Sci. Letts, 73(2-4):299-305. The average value from this study agrees well with previous estimates of the average Nd isotopic composition of the Atlantic based on analyses of ferromanganese deposits and seawater samples. However, the larger data base and the nature of the samples allow identification of distinct provenances of Nd isotopes in the Atlantic. Dept. of Geol. and Geophys., Yale Univ., New Haven, CT 06511, USA. 85:7133 Wang, Chung-Ho and Hsueh-Wen Yeh, 1985. Oxygen isotopic compositions of DSDP Site 480 diatoms: implications and applications. Geochim. cosmochim. Acta, 49(6):1469-1478. Isotope compositions vary widely, reflecting the great temperature variations and large isotopic changes of surface water in the Gulf of California; nevertheless, results can be correlated with standard oxygen isotope records for the Late Quaternary based on carbonates. Results parallel oxygen isotope data on benthic Foraminifera from Site 480, confirming that signals of environmental changes have