Stephen Clay Bowden

Research Interests

Micropaleontology, Biostratigraphy, Paleoceanography/Paleoclimatology, Petroleum Geology

Recent Research

Preliminary analysis of magnetic susceptibility data coupled with visual analysis of Deep Sea Drilling Project (DSDP) Site 242 cores has helped to determine the changes in sedimentary characteristics through the late Paleogene. Significant climate perturbations took place during the Paleogene as the Earth shifted from greenhouse to icehouse states. DSDP Leg 25, Site 242 drilled to 676 m in the western Indian Ocean (Mozambique Channel). This site is located on the eastern flank of the Davie Ridge (15 ÌŠ 50.65’S, 41 ÌŠ 49.23’E) and presently at 2275m water depth. The sedimentary succession covers both the Eocene/Oligocene and Oligocene/Miocene boundaries.

For this study, visual color changes (L*) and magnetic susceptibility data are a proxy for lithologic changes. Color variations (L*) in deep sea cores largely reflect variations in carbonate productivity and dissolution. Preliminary analysis of the Eocene/Oligocene and Oligocene/Miocene transitions by means of visual examination, core description, color imaging, reflectance spectrophotometry (L*), and magnetic susceptibility scans suggests that cyclic changes in percent carbonate might be present. Unlike what has been recorded in the equatorial Pacific Ocean (Site 1218), we do not see evidence for a two step transition in the calcite compensation depth (CCD). By documenting the carbonate changes at Site 242, we will determine the timing of changes in the CCD and look for cyclic changes in percent carbonate (%CaCO3). After completing our analysis of Site 242 we can gain a global perspective by comparing the site with the Pacific Ocean and provide data for future drilling in the Mozambique Channel. Future work will quantify the changes in percent carbonate through this critical interval and will examine the implications for the depth and fluctuations of the CCD through time. Further refinement of the planktonic foraminiferal biostratigraphy will also constrain the timing of the climatic events.

Recent Scholastic Activities

In the Spring of 2009 I participated on the GLOW cruise. This was a Mozambique Channel Seismic Site Survey of the offshore Tanzania succession that was conducted on the Pelagia (9 February to 9 March 2009). The seismic data from this cruise will be directly relevant to IODP pre-proposal 711 (Wade et al.) and will facilitate development of the full proposal (to be submitted September 2009).

I also represented Texas A&M University at the Fourteenth Annual AGU Science-Engineering-Technology Congressional Visits Day in Washington, D.C. on April 28-29.

Publications (Papers in Preparation)

Professional Experience

• 8/2008–12/2008 Teaching Assistant, Texas A&M University, College Station
  Instructed undergraduates in laboratory setting in Historical Geology (GEOL 106)
• 8/2007–5/2008 Teaching Assistant, Texas A&M University, College Station
  Instructed undergraduates in laboratory setting in Introduction to Geology (GEOL 101)
• 8/2007–11/2009 Research Assistant, Texas A&M University, College Station
  Carbonate variations in the Indian Ocean: new data from Deep Sea Drilling Project Site 242
• 8/2006–12/2007 Repository Technician, Integrated Ocean Drilling Program
  (IODP), Texas A&M University

Professional Society Memberships

• 2006–Present American Association of Petroleum Geologists
• 2007–2008 Association of Environmental and Engineering Geologists
• 2007–Present Houston Geological Society
• 2007–Present Geological Society of America
• 2008–Present Society of Exploration Geophysicists
• 2008–Present The Paleontological Society
• 2009–Present North American Micropaleontology Section, SEPM
• 2009–Present AASP - The Palynological Society

   

Abstracts and Poster Presentations

• Bowden, S. C. and Wade, B. S. Climate Change at the Eocene-Oligocene transition: new data from the Indian Ocean. Second Annual Geology and Geophysics Student Research Symposium, Texas A&M University, 11 April 2008. * Undergraduate Research Second Prize Award.
• Bowden, S. C. and Wade, B. S. Climate Change at the Eocene-Oligocene transition: new data from the Indian Ocean. Student Research Ecological Integration Symposium, Texas A&M University, 29 March 2008.
• Bowden, S. C. and Wade, B. S. Eocene-Oligocene transition: new data from Deep Sea Drilling Project Site 242. Student Research Symposium, Texas A&M University, 26 March 2008. * Winner of an International Education Week Choice Ribbon and Third Prize Award in Geology/Oceanography/Earth Science.
• Bowden, S. C. and Wade, B. S. Deep Sea Drilling Project Site 242 and Climate Change in the Past. Student Research Symposium, Texas A&M University, 26 March 2009.
• Bowden, S. C. and Wade, B. S. Deep Sea Drilling Project Site 242 and Climate Change in the Past. Second Annual Geology and Geophysics Student Research Symposium, Texas A&M University, 17 April 2009. * Ph.D. Proposal First Prize Award (tied).

Curriculum vitae

geotest.tamu.edu/userfiles/445/scbowdenCV.pdf