Sarah Carmichael Department of Geology
ASU Box 32067
572 Rivers Street
Boone, NC 28608
Phone: 828-262-8471

Fluid-Rock Geochemistry and Biomineralogy

My interests involve reactive fluid flow and mineralization in sedimentary and volcanic systems in both ancient and modern environments, as well as microbially mediated reactions at the earth's surface. I primarily focus on the geochemistry of mass extinctions and the role of tectonics in shale gas development (particularly during the late Devonian), and the geomicrobiology of cave deposits. I also work on the geochemistry of the Engare Sero Footprint Site in Tanzania.

My research involves a variety of techniques such as CL (cathodoluminescence), scanning and transmission electron microscopy (SEM and TEM), X-ray diffraction, Fourier Transform Infrared Spectroscopy (FT-IR), and stable isotope analysis (particularly strontium, carbon and oxygen). My current field areas include Tanzania, western China, western Mongolia, east Tennessee (USA), and caves in the southern Appalachians.

Research Groups

For the last six years, I have worked extensively with Dr. Suzanna Bräuer in the Department of Biology, and Dr. Cara Santelli at the Smithsonian Natural History Museum on manganese oxide biominerals produced by both bacteria and fungi. We do extensive fieldwork in southern Appalachian caves as well as on a variety of regional rocks at the surface that have experienced reactive fluid flow and/or biomineralization. For more information about our geomicrobiology research group, visit

Since 2011, I have worked with the UNESCO-funded International Geoscience Programme Project 596, which studies climate change and biodiversity in the mid Paleozoic. My main collaborators include paleontologists Dr. Johnny Waters (Department of Geology) and Dr. Erika Kido (University of Graz, Austria), and stratigrapher Dr. Thomas Suttner (University of Graz, Austria). We work primarily in the Central Asian Orogenic Belt (western China and western Mongolia) and in Europe to determine the extent and scope of Devonian ocean anoxia events, and the rebound from the mass extinctions associated with these events.

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