Paleoclimates

Paleoclimate

The objective of paleoclimatic studies at SMU is to use data from the rock record to better understand significant climatic transitions in Earth history and how these changes impacted terrestrial environments and faunas. Students are encouraged to develop interdisciplinary projects with a global perspective. Primary program strengths include sedimentology, paleopedology, and sedimentary geochemistry of terrestrial environments, with particular focus on the Permo-Triassic boundary and Late Paleozoic terrestrial ecosystems. Students benefit from departmental strengths in paleontology and stable isotope geochemistry. Domestic research projects are currently underway in Illinois, New Mexico, and Texas. Ongoing international projects involve samples collected from Argentina, Bolivia, China, Democratic Republic of Congo, Ethiopia, Morocco, and Niger.

The program is supported by the facilities of the Roy M. Huffington Department of Earth Sciences, including the Stable Isotope Laboratory and the SEM and XRD laboratories. The Stable Isotope Laboratory has Finnigan MAT 252 and MAT 253 isotope ratio mass spectrometers and peripherals for analysis of waters, carbonates, and organic materials. The VPSEM Laboratory contains a Leo-Zeiss 1450 variable pressure scanning electron microscope. Students also have access to a Rigaku Ultima III X-ray diffraction system in the departmental XRD laboratory for mineralogical studies of solid media as well as a Thermo-Fisher Scientific ARL PERFORM’X Advanced Sequential XRF Spectrometer in the XRF laboratory for chemical studies of solid and liquid media.

 

CURRENT RESEARCH

Current projects cover a wide variety of research topics:

  • Investigation of pedogenic processes in modern soils using analyses of chemical composition of soil matrix; stable carbon, oxygen, and strontium isotope composition of soil calcite and organic matter; and the hydrogen and oxygen isotope composition of pedogenic phyllosilicates
  • Using soil pCO2 estimates obtained through geochemical analysis of paleosol carbonates and co-existing organic matter as a proxy for paleoproductivity in ancient terrestrial environments
  • Determining paleoclimatic and paleoenvironmental parameters of Oligocene and Miocene terrestrial ecosystems in Ethiopia and Kenya using paleosol morphology and stable isotope geochemistry of paleosol minerals, fossil plants, and fossil vertebrate teeth
  • Developing a carbon-isotope chemostratigraphy in order to locate the stratigraphic position of the Permo-Triassic boundary in northern Texas
  • Determination of paleoatmospheric pCO2 across the Permian-Triassic boundary from paleosol minerals in strata from the Turpan Basin, Xinjiang Province, western China
  • Applying geochemical and paleopedological analyses of intercalated Permo-Carboniferous strata (cyclothems) in North America (Illinois and Kansas) and Central Europe (Bohemian Massif) in order to delineate changes in paleoenvironmental conditions during the Late Paleozoic ice age
  • Stable isotope analyses of ancient soil-formed phyllosilicates as a proxy for Late Paleozoic paleotemperatures and δ18Oprecip
  • Using δ18O values of apatitic microfossils (conodonts) as a proxy for sea-surface temperatures and the magnitude of glacioeustatic sea level fluctuations during the Late Paleozoic ice age
  • Using δ13C values and C/N ratios of organic matter preserved in urban lake sediments as indicators of historical watershed development

FACULTY AND STAFF

Neil J. Tabor, Associate Professor

 

CURRENT STUDENTS

Ph.D. Candidates
Mary Milleson
Nicholas Rosenau

 

RECENT THESES AND DISSERTATIONS

Thomas, Stephanie G. 2010. Sedimentology and Geochemistry of Upper Permian and Lower Triassic Paleosols, Northwest China: Implications for Environmental Change across the End-Permian Life Crisis. Ph.D. Dissertation, 460 pp.

Michel, Lauren A. 2009. Petrographic, Petrologic, and Isotopic Study of Paleosol Carbonates from the Permo-Pennsylvanian Lodeve Basin, France. M.S. Thesis, 267 pp.

 

SELECTED RECENT PUBLICATIONS

Mack, G.H., Tabor, N.J. and Zollinger, H.J. (2010) Palaeosols and sequence stratigraphy of the Lower Permian Abo Member, south-central New Mexico, USA. Sedimentology 57:1566–1583.

Myers, T.S., Tabor, N.J. and Jacobs, L.L. (2011) Late Jurassic paleoclimate of Central Africa. Palaeogeography, Palaeoclimatology, Palaeoecology 311:111–125.

Myers, T.S., Tabor, N.J., Jacobs, L.L. and Mateus, O. (in press) Palaeoclimate of the Late Jurassic of Portugal: comparison with the Western United States. Sedimentology.

Rosenau, N.A., Herrmann, A.D. and Leslie, S.A. (2012) Conodont δ18O values from a platform margin setting, Oklahoma, USA: Implications for initiation of Late Ordovician icehouse conditions. Palaeogeography, Palaeoclimatology, Palaeoecology 315/316:172–180.

Sheldon, N.D. and Tabor, N.J. (2009) Quantitative paleoenvironmental and paleoclimatic reconstruction using paleosols. Earth Science Reviews 95:1–52.

Tabor, N.J., Montañez, I.P., Scotese, C.R., Poulsen, C.J. and Mack, G.H. (2008) Paleosol archives of environmental and climatic history in paleotropical western Pangea during the latest Pennsylvanian through Early Permian. Geological Society of America Special Paper 441:291–303.

Tabor, N.J., Myers, T.S., Gulbranson, E., Rasmussen, C. and Sheldon, N.D. (in press) Carbon stable isotope composition of modern calcareous soil profiles in California: implications for CO2 reconstructions from calcareous paleosols. In:New Frontiers in Paleopedology and Terrestrial Paleoclimatology, SEPM Special Publication (Ed. S.D. Driese).

Tabor, N.J. and Poulsen, C.J. (2008) Late Paleozoic tropical climate and atmospheric circulation: a review of paleoclimate indicators and models. Palaeogeography, Palaeoclimatology, Palaeoecology 268:181–192

Tabor, N.J., Smith, R.M.H., Steyer, J.S., Sidor, C.A. and Poulsen, C.J. (2011) The Permian Moradi Formation of northern Niger: Paleosol morphology, petrography and mineralogy. Palaeogeography, Palaeoclimatology, Palaeoecology, 299:200–213.

Thomas, S.G., Tabor, N.J., Yang, W., Myers, T.S., Yang, Y. and Wang, D. (2011) Palaeosol stratigraphy across the Permian-Triassic boundary, Bogda Mountains, NW China: implications for palaeoenvironmental transition through Earth’s largest mass extinction. Palaeogeography, Palaeoclimatology, Palaeoecology 308:41–64.

SELECTED ABSTRACTS

Michel, L.A., Tabor, N.J. and Montañez, I.P. (2009) Diagenetic study of paleosol carbonates, Lodeve Basin, French Massif Central. Geological Society of America Abstracts with Programs 41(7):688.

Milleson, M.A. and Tabor, N.J. (2011) Geochemical analysis of lake sediments as a proxy for watershed urbanization, White Rock Lake, Dallas, TX. Geological Society of America Abstracts with Programs 43(5):226.

Myers, T.S., Tabor, N.J. and Jacobs, L.L. (2010) Correlated faunal richness and primary productivity in Late Jurassic terrestrial environments. Geological Society of America Abstracts with Programs 42(5):175.

Rosenau, N.A. and Tabor, N.J. (2010) Conodont apatite oxygen isotopes: constraining the far-field paleoenvironmental effects of glacioeustatic sea-level fluctuations associated the Late Paleozoic ice age during the Middle-Late Pennsylvanian (Desmoinesian-Missourian). Geological Society of America Abstracts with Programs 42(5):514.

Rosenau, N.A. and Tabor, N.J. (2009) Pennsylvanian (Moscovian-Gzhelian; Atokan-Virgilian) paleosols of the Illinois Basin: implications for paleoequatorial paleohydrology, climate change, and glacioeustasy. Geological Society of America Abstracts with Programs 41(7):566.

Tabor, N.J. and Kappelman, J.W. Jr. (2009) Paleoenvironments of Upper Oligocene strata, NW Ethiopian Plateau. Geological Society of America Abstracts with Programs 41(7):361.

Tabor, N.J., Myers, T.S., Mack, G.H., Renne, P.R., Mundil, R., Geissman, J.W. and Looy, C.V. (2011) “Ochoan” Quartermaster Formation of North Texas, USA, Part I: Litho- and Chemostratigraphy. Geological Society of America Abstracts with Programs 43(5):383.