Paleoclimates
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
Timothy Myers, Postdoctoral Researcher
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.
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. 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.
MANUSCRIPTS IN REVIEW
Myers, T.S., Tabor, N.J., and Jacobs, L.L. (in review) Late Jurassic paleoclimate of Central Africa. Submitted to Palaeogeography, Palaeoclimatology, Palaeoecology.
Myers, T.S., Tabor, N.J., Jacobs, L.L., and Mateus, O. (in review) Estimating soil pCO2 using paleosol carbonates: implications for correlated primary productivity and faunal richness in Late Jurassic terrestrial ecosystems. Submitted to Paleobiology.
Myers, T.S., Tabor, N.J., Jacobs, L.L., and Mateus, O. (in review) Late Jurassic paleoclimate of Portugal: comparison with the western U.S. Submitted to Sedimentology.
Rosenau, N.A., Herrmann, A.D., and Leslie, S.A. (in review) Conodont δ18O values from a platform margin setting, Oklahoma, USA: implications for initiation of Late Ordovician icehouse conditions. Submitted to Palaeogeography, Palaeoclimatology, Palaeoecology.
Tabor, N.J., Myers, T.S., Gulbranson, E., Rassmussen, C., and Sheldon, N.D. (in review) Light stable isotope composition of modern calcareous soil profiles in California: implications for paleoaltimetry and paleoatmospheric PCO2 reconstructions. Submitted to SEPM Special Publication, New Frontiers in Paleopedology and Terrestrial Paleoclimatology.
SELECTED ABSTRACTS
Michel, L.A. and Tabor, N.J. (2008) Characterization of pedogenic and diagenetic carbonates from the paleoequatorial Permo-Carboniferous Lodeve Basin, French Massif Central. Geological Society of America Abstracts with Programs 40(6):167.
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.
Michel, L.A., Tabor, N.J., and Montañez, I.P. (2007) Permo-Carboniferous climate of the Lodeve Basin, French Massif Central: relation to other paleo-equatorial records, and the penultimate icehouse-greenhouse transition. Geological Society of America Abstracts with Programs 39(6):309.
Milleson, M.E. and Tabor, N.J. (2008) Permian-Pennsylvanian climate from paleosols in north-central New Mexico, USA. Geological Society of America Abstracts with Programs 40(6):535.
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., Montañez, I., and Poulsen, C.J. (2008) Carbon isotope geochemistry of co-existing paleosol calcite and organic matter: indicator of soil CO2 concentration, actual evapotranspiration, and the driest landscapes on Earth. Geological Society of America Abstracts with Programs 40(6):48.
Tabor, N.J. and Rasmussen, C. (2008) Temperature estimates of soil processes based on δD and δ18O values of phyllosilicate: implications for CO2 forcing of atmospheric surface temperatures. Geological Society of America Abstracts with Programs 40(6):276.
Tabor, N.J. and Rasmussen, C. (2006) Observed relationships between modern soil chemistry and environmental heat transfer and its application to soil ecosystems upon a greenhouse world. Geological Society of America Abstracts with Programs 38(7):470.
Thomas, S.G., Tabor, N.J., and Yang, W. (2007) Evaluation of pedogenic calcite nodules from the Jiuyucuan Fm, NW China: implications for earliest Triassic atmospheric pCO2. Geological Society of America Abstracts with Programs 39(6):497.
Thomas, S.G., Tabor, N.J., and Yang, W. (2006) Paleoenvironmental transition across the Permian-Triassic boundary: insights from paleosols of the Junggar Basin, NW China. Geological Society of America Abstracts with Programs 38(7):532.