The Moon's nearside and farside are asymmetric in a number of ways, including crustal thickness, the abundance of erupted lavas, and in the geochemistry of the the crust itself. There is a large concentration of radioactive and geochemically-incompatible elements on the nearside. In our new paper, we showed that this enrichment in incompatible elements lowers the melting temperature of the mantle under the nearside dramatically, and likely resulted in between 4 and 13 times more magma production on the nearside early in the Moon's history, at around 4.3 billion years ago. You can check out the paper here and also UF's press release about our paper here.
The renovation and instrument installation in the Experimental Geochemistry Lab is finally complete! Now it's time to get the two Rockland piston cylinders and the Deltech gas mixing furnace up and running. There's a lot of really cool experiments to be done and I'm really looking forward to actually doing some science with these toys. But at the end of a long renovation process, I'm happy to just see the room done!
The UF Experimental Geochemistry Lab is almost ready! The contractors are hard at work and moving quickly. The cabinets and temperature controllers for the two piston cylinders are installed, the new floor is going in this week, and the instruments themselves (two piston cylinders and a Deltech furnace) will be installed soon. We expect the lab to be done and ready for setup by the end of November. I'm very much looking forward to getting to work and if you're a potential graduate student interested in joining the group, be sure to get into contact with me!
With the 50th anniversary of Apollo 11 is July, The University of Florida highlighted our work on Apollo samples and all of the interesting things we are still learning from these rocks half a century later. The article, which you can read here, also highlights the NASA mission proposal which I am a co-investigator on. We are proposing to bring new samples of the Moon back from what we believe are the youngest flood basalts on the Moon. If you want to know more about our mission proposal, we which hope is selected for flight, you can check our more details in this great article from Space.com!
My new paper in Earth and Planetary Science Letters is out and available online. This paper on how iron isotopes fractionate during core formation follows up my first paper on the topic in Nature Geoscience by provided some additional experiments and also offer a model for why we see the isotopic behavior that we observe. In the paper, my co-authors and I propose that the shortening and stiffening of Fe bonds in Fe-rich core-like alloys causes an increase in the alloys preference for heavy Fe isotopes relative to molten silicate during core formation, which is what we observe in our experiments. We also model the fractionation behavior of Fe isotopes during planetary differentiation and conclude we do not see a clear signature of isotope fractionation by vaporization or volatile depletion.
The Planetary Geochemistry Group has opportunities for highly motivated students seeking graduate degrees with an emphasis in Planetary Petrology and Geochemistry. Potential projects cover a wide range of topics including geochemical, mineralogical, and isotopic studies of planetary differentiation and core formation, the origin and evolution of the Moon’s crust and mantle, and the origins of planetary magmas. Students would join a group that utilizes experimental petrology in the newly established Experimental Geochemistry Lab, microbeam studies of meteorites and Apollo samples, and non-traditional stable isotope geochemistry to answer questions about these topics. The Department of Geological Sciences at UF is well-equipped with a wide array of instrumentation and resources available for these studies.
PhD and MSc positions are available as early as Fall 2019. For more information, please contact me (Prof. Stephen Elardo; firstname.lastname@example.org) with a C.V. and a brief description of research interests and experience.