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Volcanic ash bed dissaggregation

We have been experimenting extensively with the sediment disaggregation method of Triplehorn_(2002) using dimethyl sulfoxide (DMSO), which appears to selectively dissolve kaolinite.  We’ve found that this treatment works remarkably well for disaggregating many weakly to significantly indurated volcanic tuff samples.  … (Read More) Volcanic ash bed dissaggregation

Making shrink-teflon microcolumns for U-Pb ion chromatography

Detailed instructions for making microcolumns (50 to 100 µl) for U-Pb ion chromatography from shrink-teflon, and a lazy-susan type assembly for ≥16 simultaneous separations.  I’ve also added instructions for making larger diameter 100 µl microcolumns for common Pb separations. (Read More) Making shrink-teflon microcolumns for U-Pb ion chromatography

Supplier of quartz crucibles

We now purchase fused quartz crucibles and covers for high-T annealing zircons from AdValue Technology LLC (tel: 520-514-1100), at a significant discount compared to other large laboratory suppliers. (Read More) Supplier of quartz crucibles

Zone-refined rhenium for U-Pb

We now only use zone-refined (99.999%) rhenium ribbon from H. Cross for our U-Pb zircon analysis.  Total common Pb contents of our radiogenic Pb analyses are more consistent and lower, in the range of 0.3 to 0.5 pg; prior to … (Read More) Zone-refined rhenium for U-Pb

New age constraints on Western Gondwanan glaciation

New U-Pb zircon geochronology from the Isotope Geology Laboratory has established an unprecedented chronology of Late Paleozoic glacial deposits in western Gondwanan Paganzo and Rio Blanco basins (Argentina). Lead author Erik Gulbranson, a Ph.D. student at the University of California … (Read More) New age constraints on Western Gondwanan glaciation

Milankovitch orbital forcing of climate in the Late Paleozoic Ice Age

Dr. Vladimir Davydov, Dr. James Crowley, and Dr. Mark Schmitz report the results of new geochronology in Pennsylvanian cyclothem deposits of the Donets basin (Ukraine) in an article recently published in Geochemistry Geophysics Geosystems, the electronic journal of the American … (Read More) Milankovitch orbital forcing of climate in the Late Paleozoic Ice Age

New constraints on Snowball Earth glaciation reported in Science

Dr. Francis Macdonald, Dr. Mark Schmitz and Dr. James Crowley are co-authors on a research paper published March 5 in Science, the academic journal of the American Association for the Advancement of Science. Called “Calibrating the Cryogenian,” the article’s underlying … (Read More) New constraints on Snowball Earth glaciation reported in Science

Mass spec cleanup

We routinely boil the stainless steel portions of our turret, bead blocks, ion source lens, and filament beads in ACS-grade hydrogen peroxide to effectively remove Re buildup (no scrubbing of slit plates or filing of used filament beads needed!) and … (Read More) Mass spec cleanup

Looking for lab supplies?

Our internal lab supplies database… (IGL Laboratory Supplies) (Read More) Looking for lab supplies?

Teflon cleaning

We have found that the most efficient and effective way to clean Savillex teflon (particularly capsules for zircon dissolution) is to alternate concentrated HF (220°C) and concentrated HCl (180°C), 48 hours each for numerous iterations. This appears to “pump” trace … (Read More) Teflon cleaning