March 09, 2017
William R. Kenan, Jr., Distinguished Service Professor David Jablonski will be awarded the 2017 Paleontological Society Medal, which is the highest honor given by the Paleontological Society and is “awarded to a person whose eminence is based on advancement of knowledge in paleontology." Congratulations, David!
March 03, 2017
Postdoctoral scholar Mohit Melwani Daswani, Associate Professor (part time) Phillipp Heck, and former postdoctoral scholar Nicolas Greber analyzed a newly discovered meteorite, discovered in Northwest Africa. Oxygen isotope analyses to aid in its classification were performed at the Open University (UK). The meteorite has now been officially named Northwest Africa (NWA) 11115. The analyses show that NWA 11115 is from Mars. Specifically, it is a shergottite, and is most likely a sample of either the Tharsis volcanic province or the adjacent Amazonis-Elysium lava plains. CT scans of the meteorite can now be viewed at the Field Museum of Natural History. While NWA 11115 is petrographically and compositionally similar to other martian basaltic and martian olivine-phyric meteorites, it is geochemically distinct from other martian meteorites and from the surface of Mars, because of its anomalously low potassium to thorium (K/Th) ratio. The investigation into the cause of this anomaly is ongoing.
February 20, 2017
Louis Block Professor Nicolas Dauphas was a coauthor on a new paper in Nature Geosciences on Earth's iron fractionation. Earth has a significantly elevated level of Iron-56 relative to the chrondritic meteorites it was presuably built from. One theory was that this was due to fractionation during core-mantle segregation. Nicolas was part of a team that showed experimentally that the conditions relevant for core-mantle separation do not cause the observed fractionation, so there must be some other explanation for it.