Blair Schoene - Group, recent past and present
Kyle Samperton, Ph.D. student
My research interests focus on the application of high-precision U-Pb geochronology by thermal ionization mass spectrometry (TIMS) toward understanding processes of lithospheric magmatism. Specifically, I am interested in integrating the temporal, spatial, and chemical data recorded in accessory minerals in order to better constrain the evolution of plutons. The U-Pb system is capable of resolving geologic events with a precision of 0.1%; coupling this powerful tool with REE and trace element geochemistry can provide valuable insight into the intricacies of igneous petrogenesis. I am further interested in the development of preparatory and analytical methods for TIMS.
Brenhin Keller, Ph.D. student
My interests are centered in the fields of geochronology and high-temperature geochemistry, with particular emphasis on integrated accessory phase geochronology and trace element geochemistry. Improvements in U-Pb geochronology have pushed the frontiers of how precisely we can date processes and events in earth's history. Whether tracing the geochemical evolution of a pluton during emplacement or tracking the trace element evolution of an Archaean craton with 1 Ma precision, the integration high-precision geochronology with geochemical techniques provides fascinating new ways to observe how geological processes unfold over time.
Jennifer Kasbohm, Ph.D. Student
As geography is vital to understand patterns of glaciation and sea level rise in our present world, it is also necessary for the study of Earth’s past. Crucial Precambrian questions, ranging from the nature of Archean tectonics to the rise of animal life, depend upon knowledge of where continents were located and how quickly they moved. My research will use paleomagnetism and geochronology to find these locations and rates, and to learn more about Earth's ancient geomagnetic field. By placing these tools in the context of stratigraphic field observations, I aim to produce novel continuous records of plate motion. My first field season tackled crucial intervals in the 2.7 Ga Fortescue Formation in Pilbara, Western Australia, and I also hope to study the Ediacaran Ouarzazate Formation in Morocco.
Scott MacLennan, Ph.D. Student
Dr. Jon Husson, former Ph.D. Student (now at Univ. Wisc. Madison)
Deciphering Earth's history through the sedimentary record requires a decidedly multidisciplinary approach. Physics, chemistry, biology, mathematics and modeling can all play important roles. Among the countless questions of earth history, I am currently interested in studying how climate, ocean chemistry and biology interacted to set the stage for the rise of animals. I seek to couple geological field observations and mapping with low-temperature geochemical analyses to help contribute to this question. Additionally, I will also learn techniques of U-Pb geochronology. Absolute dates are vitally important to the study of earth history, as they help to test and constrain our models of evolutionary, chemical and climatic change.
Dr. Mélanie Barboni, former Post-doc, now at UCLA
How magmatic systems operate in the Earth’s crust – magma generation, transport and emplacement – remain challenging questions. My research integrates fieldwork with high-precision U-Pb geochronology by thermal ionization mass-spectrometry (TIMS), major and trace element geochemistry on whole rocks and accessory minerals, and thermal and rheological modeling, to understand the construction mechanisms and thermal evolution of crustal intrusions. I am further interested in understanding the development of mineral phases within magma bodies, in particular investigating the long-debated processes governing K-feldspar megacryst growth. The unparalleled time resolution offered by the TIMS dating on accessory minerals (precision of 0.1%) coupled to REE and trace element geochemistry give a new, original approach to the K-feldspar megacryst problem, documenting when and at which conditions they formed.