Brett James Tipple

brett.tipple@yale.edu

Department of Geology and Geophysics

Yale University, 210 Whitney Ave.

New Haven, Connecticut 06511

Work: (203)432-8736 Fax: (203)432-3134

 

 

EDUCATION:

Yale University: New Haven, CT

Ph.D. Candidate, Organic Geochemistry

Yale University: New Haven, CT

Masters of Philosophy, Organic Geochemistry, December 2005

Indiana University: Bloomington, IN

Bachelors of Science with Distinction, Geological Sciences, GPA 3.82/4.00, May 2003

 

CURRENT RESEARCH PROJECTS:

Dissertation Research:

 

Leaf Waxes as Environment recorders: An Empirical Evaluation and Paleoclimate Applications

My dissertation is composed of three components, tied together by the use of compound-specific isotope analysis of leaf wax lipids.

 

Origins and Evolution of the C4 Photosynthetic Pathway

I developed a long-term terrestrial plants δ13C leaf wax record from Deep Sea Drilling Project/Ocean Drilling Program cores and resultant paleo-plant community model spanning 5 million years ago (Ma) to 40 Ma. During this interval of Earth history, important climatic events occurred, including Himalayan and Andean uplift, the rise of large Antarctic icesheets, and a precipitous decrease in pCO2 from five-times current values to near-modern levels. It is likely this rapid pCO2 decrease breached a critical biochemical threshold in which CO2-concentrating C4 plants were able to outcompete non-CO2-concentrating C3 plants. Thus the history of C4 plants ultimately reflects a proxy record of terrestrial environmental change.

 

An Empirical Evaluation of Modern Tree Leaf Wax Isotopic Signals

To address uncertainties in terrestrial plant-based isotope records, I have developed an empirical study to understand environmental controls on the δD and δ13C values of leaf-wax compounds from seven specific gymnosperm and angiosperm species inhabiting the same environments and growing conditions. The approach is to extensively sample leaves from living trees spanning two well-constrained climatic gradients (Florida to Maine and east-west across Northern California) and perform compound-specific hydrogen and carbon isotope measurements on collected leaf waxes. Approximately 250 trees from the study areas will be examined. These isotopic data are compared against physical and climatic data in order to assess the relationship between environment and leaf-wax isotope ratios.

 

Terrestrial Plant Response to the Paleocene-Eocene Thermal Maximum

I developed a concentrated analysis of the Paleocene-Eocene Thermal Maximum (PETM) to study terrestrial plants’ isotopic response to a short-lived, extreme climate event. Six P/E boundary sections spanning a latitudinal transect across Northern Spain, Italy, and Tunisia were collected and extracted to assess plant community dynamics in response to the PETM. Furthermore, terrestrial plants δ13C and δD isotopic signatures are used to assess variations in carbon isotopic response to the CIE and latitudinal responses to changes in the hydrologic cycle.

 

Other Research:

Coupled (U-Th)/He-Fission Track Double Dating as a Paleo-Wildfire Proxy: Implications to the Paleocene-Eocene Thermal Maximum

In the first paleo-application of it kind, I addressed the proposed hypothesis that the PETM was caused by burning of terrestrial organic matter by analyzing detrital grains from terrestrial sediments within the Powder River and Bighorn Basins. Limited zircons recovered from Powder River Wyodak-Anderson coals are clearly volcanic in origin, roughly consistent with Absaroka volcanism. Bighorn apatite grains recovered from a series of fluvial and paleosol sediments are more intriguing, in that FT ages are nearly all ~55 Ma while He ages record more scatter and generally yield ages 55 Ma or younger. Currently, explanations for this wide distribution in He ages are equivocal. Nonetheless, the 55 Ma apatite FT ages are robust, and from a regional perspective, unlikely to have come from the Bighorn or Owl Creek Mountains. This limits us to three possible explanations for the preservation of a strong 55 Ma signal in these detrital grains; either 1) from exhumation of the Beartooth Mountains, 2) reworking of or fallout from Absaroka volcanism or, 3) resetting by wildfire at or near time of deposition.  Paleo-drainage patterns indicate the Beartooth Mountains are an unlikely source for this apatite. At this point, either Absaroka volcanism or resetting by fires remains equally plausible.

 

Senior Thesis:

Stable carbon isotopic analysis of organic matter and carbonate from the Booysens Formation, Witwatersrand Basin

The stable carbon isotopic composition of the organic matter and carbonate will be determined in a stratigraphic context using a combination of chemical extractions and stable isotopic analysis. The 2700 Ma Booysens Formation is comprised of laminated marine black shale that is a member of the Central Rand Group of the Witwatersrand Supergroup. The primary purpose of this study is to better understand the depositional environment of the Booysens shale from a 60 meter long drill core, recovered by the Harmony Gold Mine Inc., Evander #8 Shaft.

 

PROFESSIONAL AND RESEARCH EXPERIENCE:

Professional

Technical Consultant, Organic geochemistry and compound-specific isotope analysis, Biomarker Technology, Sabastopol, CA, 12/05-2/06.

Graduate Teaching Fellow, Global Environmental Change, Department of Geology and Geophysics, Yale University, Spring 2005.

Graduate Teaching Fellow, Introduction to Geochemistry, Department of Geology and Geophysics, Yale University, Spring 2004.

 

Research and Laboratory

Graduate Research Assistant, Department of Geology and Geophysics, Yale University, 08/03-present.

Organic Geochemical Laboratory, under the advisory of Dr. Mark Pagani, New Haven, Connecticut.

Undergraduate Research Assistant, Department of Geological Sciences, Indiana University, 01/02-07/03.

Biogeochemistry Laboratories, under the advisory of Dr. Lisa Pratt, Bloomington, Indiana.

Field Research Assistant, Dept. of Geological Sciences, Indiana University, 09/02-12/02.

Witwatersrand Deep Earth Microbiology Project, Republic of South Africa, western Gauteng Province. In collaboration with Princeton University, University of Tennessee, and University of the Free State.

 

PUBLICATIONS:

Pedentchouk, N., Sumner, W., Tipple, B.J., Pagani, M. (in press) δ13C and δD Composition of n-Alkanes from Modern Angiosperms and Conifers: An Experimental Set-up in central Washington State, USA, Organic Geochemistry

Tipple, B.J. & Pagani, M. (2007) The Early Origins of Terrestrial C4 Photosynthesis, Annual Review of Earth and Planetary Sciences, 35, 435-461.

Pagani, M., Zachos, J., Freeman, K. H., Tipple, B., & Bohaty, S. (2005) Marked change in atmospheric carbon dioxide concentrations during the Oligocene, Science. 309, 600-603.

Tipple, B.J. & Pagani, M. in preparation. A Neogene Higher Plant n-Alkane Carbon and Hydrogen Isotope Record from the Gulf of Mexico.

Tipple, B.J. & Pagani, M. in preparation. A Biomarker Record of the Paleogene Evolution and Expansion of C4 Plants.

Tipple, B.J., Reiners, P., Thomson, S.N., Wing, S.L., & Stewart, R.J. in preparation. A Novel Inorganic Paleo-Wildfire Indicator: Implications to the Paleocene-Eocene Thermal Maximum

 

ABSTRACTS:

Tipple, B.J., Pagani, M., Smith, R., & Anders, A., 2007. Orographic and Climatic Influence on Leaf Wax Carbon and Hydrogen Isotopic Ratios: a Field Survey From Northern California. American Geophysical Union Annual Meeting Abstracts.

Tipple, B.J., Reiners, P., Thomson, S.N., Wing, S.L., & Stewart, R.J., 2007. U-TH/HE and Fission-track Detrital Grain Double Dating as a Paleo-wildfire Indicator: Trials and Tribulations from Two Western Interior Basins and Implications to the PETM. Geological Society of America Annual Meeting Abstracts with Programs.

Pedentchouk, N., Tipple, B.J., Pagani, M., Eniola, O., & Wagner, T., 2007. Hydrogen and Carbon Isotope Compositions of n-Alkanes from Leaf Waxes in Modern Angiosperms and Gymnosperms: How Do They Compare? International Meeting of Organic Geochemstry, Torquay, England.

Tipple, B.J. & Pagani, M., 2007. Eliciting climatic controls on leaf wax carbon and hydrogen isotopic ratios: a field study from the Eastern United States. The 234th American Chemical Society National Meeting Abstracts.

Tipple, B.J. & Pagani, M., 2006. A Neogene Higher Plant n-Alkane Carbon and Hydrogen Isotope Record From the Gulf of Mexico. American Geophysical Union Annual Meeting Abstracts.

Tipple, B.J. & Pagani, M., 2006. A Late Miocene n-Alkane δD and δ13C Record from the Gulf of Mexico. Geological Society of America Annual Meeting Abstracts with Programs.

Tipple, B.J. & Pagani, M., 2005. A Biomarker Record of the Paleogene Evolution and Expansion of C4 Plants. Geological Society of America Annual Meeting Abstracts with Programs.

Pagani, M. & Tipple, B.J., 2005. The influence of C4 photosynthesis during the Miocene. Goldschmidt Conference,

Grocke, D.R., Tipple, B.J., & Pagani, M., 2004. A Cenozoic Terrestrial Isotope Record and Evolution of C4 Photosynthesis. American Geophysical Union Annual Meeting Abstracts.

Tipple, B.J. & Pagani, M., 2004. Long-term Regional Contributions of Cenozoic C4 Plants to Marine Sediments. Geological Society of America Annual Meeting Abstracts with Programs.

Tipple, B.J., Pagani, M., & Veach, A., 2004. C4 Plant Distribution during the Cenozoic: Approach and Preliminary Evidence. Gordon Research Organic Geochemistry Conference.

Yong, H., Liang, S., Tipple, B.J., Pagani, M., & Briggs, D., 2004. Carbon Isotopic Compositions of in-situ n-alkanes from an Arctic Eocene Deciduous Flora: Were They Influenced by the Unique Polar Light Regime? Gordon Research Organic Geochemistry Conference.

Boice, A.E., Tipple, B.J., & Pratt, L.M, 2003. Isotopic Evidence for Microbial Sulfate Reduction and Methanotrophy during the Late Archean, Witwatersrand Basin, South Africa. Geological Society of America, Annual Meeting Abstracts with Programs.

Moser, D., Gihring, T., Fredrickson, J., Brockman, F., Onstott, T.C., Hall, J., Lin, L., Davidson, M., Balkwell, D., Drake, G., Trimarco, E., Pfiffner, S., Peacock, A., Welty, A., Southam, G., Lengke, M., Wanger, G., Tipple, B.J., Sherwood-Lollar, B., & Ward, J., 2003. Microbiological, Geochemical, and Hydrological Linkage Over 2.5 km of a Vertically Circulating Continental Fissure System: American Society for Microbiology.

 

PRESENTATIONS:

2007

Orographic and Climatic Influence on Leaf Wax Carbon and Hydrogen Isotopic Ratios: a Field Survey From Northern California. (Poster) Tipple, B.J., Pagani, M., Smith, R., & Anders, A., American Geophysical Union Annual Meeting, December, 2007.

U-TH/HE and Fission-track Detrital Grain Double Dating as a Paleo-wildfire Indicator: Trials and Tribulations from Two Western Interior Basins and Implications to the PETM. (Oral) Tipple, B.J., Reiners, P., Thomson, S.N., Wing, S.L., & Stewart, R.J., 2007. Geological Society of America Annual Meeting, November, 2007.

Eliciting climatic controls on leaf wax carbon and hydrogen isotopic ratios: a field study from the Eastern United States. (Oral) Tipple, B.J. & Pagani, M., 2007. The 234th American Chemical Society National Meeting, August, 2007.

2006

A Neogene Higher Plant n-Alkane Carbon and Hydrogen Isotope Record From the Gulf of Mexico. (Poster) Tipple, B.J. & Pagani, M., American Geophysical Union Annual Meeting, December, 2006.

A Late Miocene n-Alkane δD and δ13C Record from the Gulf of Mexico. (Poster) Tipple, B.J. & Pagani, M., Geological Society of America Annual Meeting, November, 2006.

Coupled Late Miocene n-Alkane δD and δ13C Records from the Gulf of Mexico: Preliminary Results (Poster) Tipple, B.J. & Pagani, M., Gordon Research Organic Geochemistry Conference. August, 2006.

2005

A Biomarker Record of the Paleogene Evolution and Expansion of C4 Plants. (Oral) Tipple, B.J. & Pagani, M., Geological Society of America Annual Meeting. November, 2005.

A Cenozoic Higher Plant Biomarker Record: Initial Results and Issues. (Oral) Tipple, B.J. Yale University Sediment Seminar. November, 2005.

Inorganic Fire Indicators: Implications to the Paleocene-Eocene Thermal Maximum. (Oral) Tipple, B.J. Yale University Sediment Seminar. February, 2005.

2004

Long-term Regional Contributions of Cenozoic C4 Plants to Marine Sediments. (Oral) Tipple, B.J. & Pagani, M., Geological Society of America Annual Meeting. November, 2004.

C4 Plant Distribution during the Cenozoic: Preliminary Evidence. (Oral) Tipple, B.J. Yale University Sediment Seminar. November, 2004.

C4 Plant Distribution during the Cenozoic: Approach and Preliminary Evidence. (Poster) Tipple, B.J., Pagani, M., & Veach, A., Gordon Research Organic Geochemistry Conference. August, 2004.

Organic Geochemical Methods for Determination of Cenozoic Higher-Plant Paleoecology: Theory and Preliminary Results. (Oral) Tipple, B.J. Yale University Sediment Seminar. April, 2004.

2003

Carbon Isotopic Evidence for a Methane-Supported Microbial Community from a Late Archean Silty Shale: Witwatersrand Basin, South Africa. (Poster) Tipple, B.J., Carnegie Institute, Washington D.C. May, 2003.

 

 

Memberships:

  • American Chemical Society, 2006-present
  • American Geophysical Union, 2004-present
  • Geological Society of America, 2003-present
  • American Association of Petroleum Geologists, 2002-present
  • Sigma Gamma Epsilon Geological Honors Society, 2002-present
  • National Society of Collegiate Scholars, 1999-present

 

Honors/Awards:

  • John F. Enders Fellowship & Research Grant, Yale University (2006)
  • Geological Society of America, Graduate Student Research Grant (2005)
  • Yale Institute of Biospheric Studies, Field Ecology Grant (2004)
  • Graduate Research Fellowship, National Science Foundation (2004-2007)
  • University Fellowship, Yale University (2003)
  • Best Undergraduate Research Project, Indiana University (2003)
  • William C. Menke Scholarship, Indiana University (2002)
  • Bill Armstrong/Little 500 Scholarship, Indiana University Student Association (2002)
  • Charles Deiss Scholarship, Indiana University Department of Geological Sciences (2001)
  • Elected Phi Beta Kappa, Indiana University (2001)