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Useful references for calcium carbonate samplesIAEA Isotope Hydrology Laboratory PublicationsIAEA Isotope Hydrology Laboratory Publications δ18O based paleotemperature equation from carbonates.Dual-Inlet Source Mixing Characterization.Meijer et al., Cross contamination in dual inlet isotope ratio mass spectrometers, International Journal of Mass Spectrometery, 198, 45-61, 2000. McCrea, J. M., On the Isotopic Chemistry of Carbonates and a Paleotemperature Scale, J. Chem. Phys. 18, 849 (1950); doi:10.1063/1.1747785 Tyler B. Coplen, Carol Kendall & Jessica Hopple, Comparison of stable isotope reference samples, Nature 302, 236 - 238 (17 March 1983); doi:10.1038/302236a0 17O correction.Kaiser, J., Reformulated 17O correction of mass spectrometric stable isotope measurements in carbon dioxide and a critical apraisal of histroic 'absolute' carbon and oxygen isotope ratios, Geochimica et Cosmochimica Acta, 72, 1312-1334 (2008) Brand, W., Assonov, S. & Tyler B. Coplen, Correction for the 17O interference in δ(13C) measurements when analyzing CO2 with stable isotope mass spectrometry (IUPAC Technical Report), Pure and Applied Chemistry, 82, 8, 1719-1733 (2010) Aragonite Notes:For those of you running aragonite for d18O using phosphoric acid digestion: raise your hand if you take into account the different acid fractionation of aragonite relative to calcite as in Kim et al. 2007. Kim S-T, Mucci A, Taylor BE. 2007. Phosphoric acid fractionation factors for calcite and aragonite between 25 and 75 *C: revisited. Chemical Geology 246: 135-146. If you run the kiel at 70*C, your aragonites would be 0.3772 permil heavier. Thank you. Andrew Schauer Dolomite proceduresThe selective acid extraction method of Al-Aam et al. (1990). has been commonly used to distinguish the C and O isotopic composition of different carbonate components that are composed of the mixture of calcite and dolomite. The mixture powder (~50 mg) was reacted in three steps: (1) with >100% H3PO4 at 25°C for 2 h in vacuum to extract CO2 from the calcite fraction, (2) continuously with >100% H3PO4 at 25°C for 24 h in vacuum to extract CO2 from the calcite-dolomite mixture, (3) the remaining material was reacted at 50°C for more than 100 h to obtain CO2 from the dolomite. A further discussion on this method was presented by Yui and Gong (2003). Al-Aasm, I.S., Taylor, B.E., South, B., 1990. Stable isotope analysis of multiple carbonate samples using selective acid extraction. Chem. Geol. 80, 119-125. Yui, T.-F. and Gong, S.-Y., 2003. Stoichiometry effect on stable isotope analysis of dolomite. Chem. Geol. 201, 359-368. i/Clean /Apatite proceduresThere has been a discuss on this among apatite dissolvers recently. It is very important to heat, under vacuum for at least an hour, to remove water and then to load the samples immediately for the run. Ross Secord at Nebraska heats to as high as 200°C (). Most everyone else heats to 65-80°C. DO NOT heat at very high T (>200°C). You will begin to lose carbonate. I think 200°C is a little risky, but Ross has a specific scientific question that justifies higher temperatures. International StandardsJust want to make people aware that IAEA-CO-9 (BaCO3) may also possess a problem similar to that of LSVEC. When we evaluated LSVEC, we carried out a CO2 equilibration test by exposing LSVEC with CO2 gas having a δ13CVPDB value of −4.02 mUr (also know as ‰). Several other materials, IAEA-CO-9, IAEA-603, commercial CaCO3, and glutamic acids, were also tested in the same run. All samples were loaded into an 8-L glass desiccator. A vial of water was also placed inside desiccator to ensure a humid environment. The desiccator was evacuated, and approximately 300 μmol of CO2 was introduced into the desiccator. After 14 days at ambient temperature, the samples were removed from the desiccator and dried in a vacuum oven at 40 °C for 4 hr. For comparison, a set of control samples, which were not equilibrated with CO2, were analyzed. The results shown that LSVEC and IAEA-CO-9 reacted with CO2, and their δ13C values increased by 1.02 mUr and 0.76 mUr respectively. There was no evidence of reaction or exchange between CO2 and other materials that were tested in the same run. Another test we performed was to compare the δ13C values from frequently opened vials and a newly opened vial of IAEA-CO-9. The δ13C value from the frequently opened vial measures 0.19 ± 0.05 mUr more positive than that of a newly opened vial of IAEA-CO-9. Further testing is needed on IAEA-CO-9 to confirm whether other laboratories also observe this behavior. Although particle size is an important criterion in carbonate oxygen isotopic reference materials, based on our observation the particle size may not be the cause of the increasing δ13C value of LSVEC and IAEA-CO-9. Indeed, both LSVEC and IAEA-CO-9 are quite fine compare to IAEA-603 and NBS 19; however, one of the commercial CaCO3 reagents proposed as a replacement for LSVEC by Willi Brand is as fine as (from visual observation) LSVEC and IAEA-CO-9 and the δ13C value of this reagent is not affected by equilibration with CO2 in a humid environment. Let's wait for Sergey's report to find out the causes of the increase in δ13C value of LSVEC. Best regards, Haiping Qi (Isogeochem post 2/10/2016) Window 10 Isodat install in 32-bit Legacy ModeI am on day 3 with Windows 10 and Isodat 3.0.88 running a Delta XP with fiberline driver. No crashes or weirdness yet running sequences and routine procedures. To get to this point I have went through the following steps: Computer is a local custom build with the latest hardware (8th gen Intel). Benjamin Harlow, Washington State University. July 2018 Kiel Carbonate Device and MAT 253 Manuals and Brochures.Kiel IV Carbonate Device Manual Kiel IV Carbonate Device Brochure |
 NEWS & EVENTSSIL Co-Founder Paul Koch and colleagues review Sundance Film Festival movies for Science magazine. SIL Co-Director Matt McCarthy recieved a NSF Major Research Instrumentation award for new compound specific isotope ratio mass spectrometers. SIL Co-Director Matt McCarthy directed a weekend program for about 40 Educational Opportunity (EOP) STEM transfer students highlighting the use of stable isotope analyses in phyiscial and biological science inquiry. SIL Co-Director Jim Zachos appointed to Ida Benson Lynn Endowed Chair in Ocean Health. UC Santa Cruz biologists Daniel Costa and Luis Huckstadt found valuable samples for comparison of modern Weddell seals to century-old pelts found in the huts of Antarctic explorers Ernest Shackleton and Robert Falcon Scott. Their findings reveal changes in the Ross Sea ecosystem. SIL Co-director Jim Zachos elected to be a member of the National Academy of Sciences! UCSC Stable Isotope Laboratory data used to show threatened grizzly bears in Yellowstone National Park have a vital hankering for a dwindling supply of pine nuts. SIL Co-director and UCSC Physical and Biological Sciences Dean Paul Koch has been elected 2015 AAAS Fellow for "energetic and innovative leadership in applying stable isotope geochemistry to document and interpret environmental change through the past 65 million years of Earth history.". SIL Co-director Jim Zachos has been awarded the 2016 Milutin Milankovic Medal by the European Geosciences Union. Formation of coastal sea ice in North Pacific drives ocean circulation and climate. So indicates evidence published by UCSC scientists Karla Knudson and Christina Ravelo. Christina Ravelo, Professor of Ocean Sciences at UC Santa Cruz and UCSC Stable Isotope Laboratory co-director, has received the 2013-14 Outstanding Faculty Award from the Division of Physical and Biological Sciences. The annual award is the division's highest honor for faculty achievement, recognizing combined excellence in research, teaching, and service. Long-term human influenced dietary habits of Yosemite National Park black bears explored by UCSC scientist Jack Hopkins, Paul Koch, and colleagues. SIL Co-Director Paul Koch honored as a Fellow of the California Academy of Sciences. See story here. Diversity of great white shark diet was shown to be greater than previously thought based on research by UC Santa Cruz colleagues Sora Kim, Paul Koch, and James Estes along with co-author M. Tim Tinker of the U.S. Geological Survey. This work was highlighted in the Los Angeles Times. SIL Co-Director Paul Koch has been named Dean of the UC Santa Cruz Division of Physical and Biological Sciences. Madagascar Lemur extinctions and ecological retreat followed arrival of humans according to UCSC Graduate Student Brooke Crowley, Professor Paul Koch and co-authors. Their findings were recenlty published in the journal Proceedings of the Royal Society B. SIL Co-Director Paul Koch was quoted in the New York Times on research showing that a tiny Paleocene horse Sifrhippus, the first horse, grew even smaller during the Paleocene-Eocene Thermal Maximum climatic warming event. SIL Co-Director Christina Ravelo has been selected as an American Geophysical Union (AGU) Fellow. SIL Co-Directors Paul Koch and Jim Zachos's research on Paleocene-Eocene Thermal Maximum (PETM) climatic warming event is featured in an National Geographic article "Earth Before the Ice" in the October 2011 issue. SIL Co-Director Paul Koch has been appointed Interim Dean of the UC Santa Cruz Division of Physical and Biological Sciences. SIL Co-Director Jim Zachos elected to the American Academy of Arts and Sciences. UCSC's SIL new ThermoScientific MAT 253 isotope ratio mass spectrometer coupled to a Kiel Automated Carbonate Device begins regular operations. UCSC's SIL retires its 15 year-old dual-inlet Optima following a very productive career. The instrument generated over 40,000 data points. Two Tsavo Lions In Famed Killings Get Partial Reprieve according to UCSC Graduate Student Justin Yeakel. Listen to Justin's inteview on National Public Radio's All Things Considered: SIL co-director Christina Ravelo (Ocean Sciences) sails as co-chief scientist on Integrated Ocean Drilling Project (IODP) Expedition 323 to investigate Bearing Sea Paleoceanography.
SIL co-director Christina Ravelo (Ocean Sciences) gives the 2008 Emiliani Lecture at the American Geophysical Union Meeting in San Francisco on "Lessons from the Pliocene Warm Period and the Onset of Northern Hemisphere Glaciation".
UCSC SIL has been funded by the National Science Foundation for a new Dual-Inlet Isotope Ratio Mass Spectrometer with individual acid drip system for very small calcium carbonate samples. SIL co-director Jim Zachos (Earth and Planetary Sciences) recieves prestigious Humbolt Research Award. See Humbolt Award for details. SIL Co-Director Jim Zachos has been selected as an American Geophysical Union (AGU) Fellow. In recognition of the new continuous flow instruments added to the UCSC stable isotope facility a Symposium is being run to highlight the new analytical capabilities. |
