Application of secondary ion mass spectrometry to the determination of Mg/Ca in rare, delicate, or altered planktonic foraminifera : examples from the Holocene, Paleogene, and Cretaceous
Bice, Karen L.
Layne, Graham D.
Dahl, Kristina A.
MetadataShow full item record
Secondary ion mass spectrometry (SIMS) is useful for measuring Mg/Ca in both primary calcite and diagenetic minerals in planktonic foraminifera. The excellent spatial resolution (<10 μm) and small amount of material removed (<2 ng) makes it easy to avoid targets that include obvious embedding material and encrusting or infilling minerals such as secondary calcite and authigenic clays in diagenetically altered samples. Because analyses can be performed on individuals, SIMS is also a viable technique for generating Mg/Ca values from sediment samples in which foraminifera are rare or have low mass. For clean primary calcite samples, Mg/Ca ratios from SIMS compare well to those obtained using inductively coupled plasma mass spectrometry (ICP-MS), while maintaining information regarding the true variability of elemental ratios within individual tests. For samples with secondary calcite or stubbornly adhering clays, SIMS enables us to accurately measure primary calcite compositions and to assess and reconcile contamination problems in bulk samples analyzed by solution-based ICP-MS. We have observed that SIMS is an invaluable and reliable tool for the identification and avoidance of problems of diagenesis and the analysis of rare or delicate planktonic foraminifera. However, because of operator time required to properly target delicate (thin-walled) or contaminated planktonic foraminifera, SIMS may not be feasible for Mg/Ca studies where large numbers (hundreds) of samples must be processed and bulk measurements on multiple individuals will suffice.
Author Posting. © American Geophysical Union, 2005. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 6 (2005): Q12P07, doi:10.1029/2005GC000974.
Showing items related by title, author, creator and subject.
Mohtadi, Mahyar; Oppo, Delia W.; Steinke, Stephan; Stuut, Jan-Berend W.; De Pol-Holz, Ricardo; Hebbeln, Dierk; Luckge, Andreas (2011-06)The Australian-Indonesian monsoon is an important component of the climate system in the tropical Indo-Pacific region. However, its past variability, relation with northern and southern high latitude climate and connection ...
Thornalley, David J. R.; Blaschek, M.; Davies, F. J.; Praetorius, S.; Oppo, Delia W.; McManus, Jerry F.; Hall, Ian R.; Kleiven, Helga F.; Renssen, H.; McCave, I. Nick (Copernicus Publications on behalf of the European Geosciences Union, 2013-09-03)The overflow of deep water from the Nordic seas into the North Atlantic plays a critical role in global ocean circulation and climate. Approximately half of this overflow occurs via the Iceland–Scotland (I–S) overflow, yet ...
Hu, Dengke; Clift, Peter D.; Boning, Philipp; Hannigan, Robyn E.; Hillier, Stephen; Blusztajn, Jerzy S.; Wan, Shiming; Fuller, Dorian Q. (John Wiley & Sons, 2013-07-26)Sediments in the Pearl River delta have the potential to record the weathering response of this river basin to climate change since 9.5 ka, most notably weakening of the Asian monsoon since the Early Holocene (∼8 ka). Cores ...