Bright, J., Ebert C., KOSNIK M. A. T. T. H. E. W. A., Southon J. R., Whitacre K., Albano P. G., Flores C., Frazer T. K., Hua Q., Kowalewski M., Martinelli J. C., Oakley D., Parker W. G., Retelle M., RITTER M. A. T. I. A. S. D. O. N. A. S. C. I. M. E. N. T. O., Rivadeneira M. M., Scarponi D., Yanes Y., Zuschin M., & KAUFMAN D. A. R. R. E. L. L. S.
(2021).
COMPARING DIRECT CARBONATE AND STANDARD GRAPHITE 14C DETERMINATIONS OF BIOGENIC CARBONATES.
Radiocarbon. 1-17., 2021: Cambridge University Press
Abstractn/a
The direct carbonate procedure for accelerator mass spectrometry radiocarbon (AMS 14C) dating of submilligram samples of biogenic carbonate without graphitization is becoming widely used in a variety of studies. We compare the results of 153 paired direct carbonate and standard graphite 14C determinations on single specimens of an assortment of biogenic carbonates. A reduced major axis regression shows a strong relationship between direct carbonate and graphite percent Modern Carbon (pMC) values (m = 0.996; 95% CI [0.991–1.001]). An analysis of differences and a 95% confidence interval on pMC values reveals that there is no significant difference between direct carbonate and graphite pMC values for 76% of analyzed specimens, although variation in direct carbonate pMC is underestimated. The difference between the two methods is typically within 2 pMC, with 61% of direct carbonate pMC measurements being higher than their paired graphite counterpart. Of the 36 specimens that did yield significant differences, all but three missed the 95% significance threshold by 1.2 pMC or less. These results show that direct carbonate 14C dating of biogenic carbonates is a cost-effective and efficient complement to standard graphite 14C dating.
Frozza, C. F., Pivel M. A. G., Suárez-Ibarra J. Y., Ritter M. N., & Coimbra J. C.
(2020).
Bioerosion on late Quaternary planktonic Foraminifera related to paleoproductivity in the western South Atlantic.
Paleoceanography and PaleoclimatologyPaleoceanography and Paleoclimatology. n/a(n/a), e2020PA003865., 2020: John Wiley & Sons, Ltd
Abstractdoi: 10.1029/2020PA003865
Key Points: For the first time, drill holes in planktonic Foraminifera from the western South Atlantic were compared with paleoceanographic proxies. Paleoproductivity of the western South Atlantic was reconstructed using assemblage and geochemical indexes for the last 46 kyr. Paleoproductivity estimates and bioerosion rates of planktonic foraminiferal tests show a strong relation during late Quaternary.
do Ritter, M. N., Francischini H., Kuhn L. A., da Luz N. C., Michels F. H., de Morais A. L. M., Paim P. A. V., Xavier P. L. A., & de Francesco C. G.
(2016).
El sesgo del operador en la replicabilidad de los estudios tafonómicos comparativos.
Revista Brasileira de Paleontologia. 19, 449–464., jan, Number 3: Sociedade Brasileira de Paleontologia
Abstractn/a