Geology and Geological Engineering

Dr. Sarah W. Keenan
Geobiology in Modern and Ancient Systems
Research Teaching People News & Links Publications CV

News and Upcoming Events

Spring 2021:

  • Congratulations to Grace on successfully defending her MS Paleo thesis titled: Using fossil bone geochemistry and age reports to reconstruct diagenesis at the Pig Dig Site, Badlands National Park, SD! Grace will start a Scientists in the Park position at Badlands this May after graduation.
  • Congratulations to Michael on being awarded a SD Space Grant Consortium Graduate Student Research Stipend, funded by NASA, to support your MS research on cave geomicrobiology in the Black Hills!

    Fall 2020:

  • Welcome to Michael, Jessica, and Colleen, new MS Paleontology graduate students!
  • New publication: Congratulations to Alex for leading this awesome study! Emmons, A.L., Mundroff, A.Z., Keenan, S.W., Davoren, J., Andronowski, J., Carter, D. O., and DeBruyn, J.M. (2020). Characterizing the postmortem human bone microbiome from surface decomposed remains. PLoS One, 15:e0218636, DOI:10.1371/journal.pone.0218636. article link .

    Spring 2020:

  • Despite the abrupt end to the semester, Michael and Zakary completed their projects, Grace successfully defended her proposal, we're slowly returning to a new normal, and preparing for Fall.
  • Congratulations to Grace for receiving the AAPS Charles Sternberg Scholarship AND the Richard Osgood Award through the Paleontological Society to support her research on the Pig Dig Site at Badlands National Park! This funding will help to support lab-based analyses of the fossils, travel to visit the Pig Dig Site, computational support, and supplies for the curation of fossils in SDSMT collections.
  • Congratulations to Michael as well for receiving funding through the Geological Society of America, Rocky Mountain Section to support his undergraduate research! He will use the funding to purchase safety equipment to allow for continued (and expanded!) sampling this summer at Rushmore Cave. Thank you to all the funders for supporting student research at Mines!

    February 2020:

  • Busy month in the lab! Michael and I have been collecting samples every other week, and Michael is busy analyzing the data from sampling efforts in Rushmore Cave. Zakary is also busy collecting weekly data from his mesocosm experiments in the lab.
  • New publication: Fanter, C.E., Lin, Z., Keenan, S.W., Janzen, F.J., Mitchell, T.S., and Warren, D.E. (2020). Development-specific transcriptomic profiling suggests new mechanisms for anoxic survival in the ventricle of overwintering turtles. Journal of Experimental Biology, 223, DOI: 10.1242/jeb.213918. article link .

    November 2019:

  • Field work with Michael continues! We are busy collecting samples and analyzing data from our bi-monthly visits to Rushmore Cave. Zakary also collected soils and some preliminary data from his senior research project focused on carbon cycling in soils at Kenny Brown's ranch in Hermosa. Poster presentations will be Dec. 6th in PRL!

    October 2019:

  • Field work with Michael begins! We spent a lovely Saturday collecting data (temperature, carbon dioxide, relative humidity) in Rushmore Cave with the assistance of Kevin Chase for Michael's senior research project.
  • New publication: Keenan, S.W., Schaeffer, S.M, and DeBruyn, J. M. (2019). Spatial changes in soil stable isotopic composition in response to carrion decomposition. Biogeosciences, 16:3929-3939, DOI: 10.5194/bg-16-3929-2019. article link .

    July 2019:

  • Workshop Participation: Dr. Keenan participated in the Early Career Geoscience Faculty Workshop in College Park, MD. In addition to learning invaluable teaching and research skills, this was also a great networking opportunity! #EarlyCareer2019
  • New publication: Keenan, S.W. and DeBruyn, J. M. (2019). Changes to vertebrate tissue stable isotope (δ15N) composition during decomposition. Scientific Reports, 9:9929, DOI: 10.1038/s41598-019-46368-5. article link .

    April 2019:

  • Congratulations to Seth for winning 2nd place in the SDSMT Student Research Symposium for his poster titled: Taphonomic survey of vertebrate fossils from the Pierre Shale near Hermosa, SD. Great job Seth!
  • New publication: Keenan, S.W., Pasteris, J.D., Wang, A., and Warren, D.E. (2019). Heterogeneous bioapatite carbonation in western painted turtles is unchanged after anoxia. Comparative Biochemistry and Physiology, Part A article link . This is part of a special issue on Acid-Base physiology!

    January 2019:

  • Lab setup continues, and the Licor-830 CO2 analyzer (dubbed Yoda) is up and running! This will allow us to measure how soil microorganisms respond to changes in nutrients in the lab and in the field.
  • Seth is continuing his undergraduate research (GEOL 465) and is busy in collections examining fossil bones from the Pierre Shale. Once the snow melts, we will be out in the field to assess fossil weathering in-situ.

    December 2018:

  • Lab setup is moving forward, and we should have a Licor-830 CO2 analyzer up and running shortly!
  • New publication: Keenan, S.W., Emmons, A.L., Taylor, L.S., Phillips, G., Mason, A.R., Mundorff, A., Bernard, E.C., Davoren, J., and DeBruyn, J.M. (2018). Spatial impacts of a multi-individual grave on microbial and microfaunal communities and soil biogeochemistry. PLoS One article link .

    October 2018:

  • Field work with Seth! We spent a lovely October day with Kenny Brown prospecting for Late Cretaceous marine fossils in the Pierre Shale. Thanks to GPS, we can check back on our taphonomy sites in the spring!
  • Calen and Seth are working on their undergraduate senior research projects and making plans for data collection and analysis this semester and next. Exciting taphonomy research ahead!

    August 2018:

  • Dr. Keenan arrived at SDSM&T! Lab set-up is currently underway, and two undergraduate students should begin their senior research projects within the next few months!
  • New publication: Odegard, D.T., Sonnenfelt, M.A., Bledsoe, J.G., Keenan, S.W., Hill, C.A, and Warren, D.E. (2018). Changes in the material properties of the shell during simulated aquatic hibernation in the anoxia-tolerant painted turtle. Journal of Experimental Biology article link . See the affiliated Inside JEB article

  • Contact: Dept. of Geology and Geological Engineering, 501 E. Saint Joseph St., SDSMT, Rapid City, SD 57701
    Phone: (605)394-2461 / Fax: (605)394-6703 / Email: / Updated: 20 April 2021