Funded by grant EAR-0216179 from the National Science Foundation

What it does: Measures isotope ratios of C, O, and N from geological and biological samples.

How it works: Oxygen, Carbon, or Nitrogen must be separated from samples by some chemical method (such as combustion, dissolution in acids, or fusing with a laser in the presence of an oxidizer). Gasses are then purified in a vacuum line (glass trellis-work in picture) or within the elemental analyzer. The purified gasses are then introduced into the mass spectrometer, either by using the dual-inlet system or continuous flow mode, where they are bombarded by electrons and ionized. The ions travel down a flight tube and are separated according to mass by an electromagnet. The ions are then detected in Faraday cups at the end of the flight tube. The isotope ratio is calculated from the charge of the ions at the end of the flight tube. See Finnigan's brochure for instrument and analytical statistics.
    Although the differences in mass between the isotopes of the light gasses are small (~11% between ¹⁶O and ¹⁸O), the isotope ratio is very sensitive to geological processes. Stable isotopes are commonly used in studies to determine paleoclimate, water-rock interaction, and metamorphic temperatures in rocks, and trophic level and paleodiet in fossils.

Research Projects: The lab is used for class projects in Geology and other departments (e.g. Enst 100 Earth and Environmental Processes, Fsem 124 Forensic Geology, Geol 310 Economic Geology, Geol 415 Marine Geology, Geol 411 Isotope Geology, Biol 476 Biodiversity and Ecosystem Ecology). Class projects have investigated plant physiology, lake sediments near Hamilton, the origin of Pb-Zn ore deposits, and adulteration of maple syrup. Many students have used the lab for independent study projects and senior theses, and several of these projects have been presented at regional and national meetings.

Papers from the Isotope Lab:
(* indicates collaborative research with students)

Peck, WH, and *Tubman, SC, 2010, Changing carbon isotope ratio of atmospheric carbon dioxide: Implications for food authentication, Journal of Agricultural and Food Chemistry. DOI: 10.1021/jf100104s

Peck, WH, Volkert, RA, *Mansur, A, *Doverspike, BA, 2009, Stable isotope and petrologic evidence for the origin of regional marble-hosted magnetite deposits and the zinc deposits at Franklin and Sterling Hill, New Jersey Highlands: Economic Geology, v. 104, p. 1037-1054.

Peck, WH, and *Tumpane, KP, 2007, Low carbon isotope ratios in apatite: An unreliable biomarker in igneous and metamorphic rocks. Chemical Geology, v. 245, p. 305-314.

Peck, WH, Volkert, RA, *Meredith, MT, and *Rader, EL, 2006, Calcite-graphite carbon isotope thermometry of the Franklin Marble, New Jersey Highlands: Journal of Geology, v. 114, p. 485-499.

Peck, WH, *DeAngelis, MT, *Meredith, MT, *Morin, E, 2005, Polymetamorphism of marbles in the Morin terrane (Grenville Province, Quebec): Canadian Journal of Earth Sciences, v. 42, p. 1949-1965.

Abstracts from the Isotope Lab:
(* indicates collaborative research with students)

April, RH, *Coplin, AL, 2008, The isotopic composition of organic carbon in Adirondack Spodosols, Geochimica et Cosmochimica Acta, v. 72, Issue 12, p. A30.

*Eppich, GR, and Peck, WH, 2006, Stable isotope geochemistry of the Kilmar magnesite deposits, Grenville Province, Quebec: Geological Society of America Abstracts with Programs, v.38, n. 2, p. 26.

Goldstein, AG, Peck, WH, and Selleck, BW, *King, M, *Coliacomo, E, Kita, NT, Valley, JW, 2006, High-resolution stable isotope thermometry of Taconic strain fringes: Geological Society of America Abstracts with Programs, v. 38, n. 7, p. 18.

*Kinsman, N, Goldstein, A, Peck, W, and Selleck, B, 2006, Stable isotopes of strain fringes in Aptian slates near Lourdes, France: Geological Society of America Abstracts with Programs, v.38, n. 2, p. 26.

*King, M, *Coliacomo, E, Goldstein, A, Peck, W, and Selleck, B, 2006, Stable isotopes in strain fringes from the Taconic Mountains, Vermont: Geological Society of America Abstracts with Programs, v.38, n. 2, p. 26.

*Meredith, MT, *Doverspike, BA, Peck, WH, 2003, Stable isotope geochemistry of the Franklin Marble (Grenville Province, New Jersey), Geological Society of America Abstracts with Programs, v.35, n. 3, p. 96.

*Nowak, R, (rnowak09@wooster.edu) Peck, WH, Pollock, M, 2009, Protolith determination of the Hyde School garnet-sillimanite marginal gneisses, Adirondack Lowlands, NY: Geological Society of America Abstracts with Programs, v. 41(4), p. 52.

Peck, WH, *DeAngelis, MT, *Meredith, MT, *Morin, E, 2004, Metamorphism of marbles in the Morin terrane (Grenville Province, Quebec), Geological Society of America Abstracts with Programs, v.36, n. 5, p. 460.

Peck, WH, and *Tumpane, KP, 2006, Low carbon isotope ratios in high-temperature apatite: Implications for use as a biomarker: Geological Society of America Abstracts with Programs, v. 38, n. 7, p. 46.

Peck, WH, Volkert, RA, *Mansur, AT, Doverspike, BA, 2008, Stable isotope constraints on the origin of Mesoproterozoic marble-hosted zinc and iron deposits, New Jersey Highlands: Geological Society of America Abstracts with Programs, v. 40(2), p. 61.

Peck, WH, Volkert, RA, *Mansur, AT, *Eppich, GR, 2008, A Stable Isotope Perspective on Sedimentation, Ore Genesis, and Metamorphism in the Southern Grenville Province: Geological Society of America Abstracts with Programs, v. 40(6), p. 234.

Selleck, BW, Peck, WH, McLelland, JM, *Bergman, M, *Ellis, A, *Conti, C, 2008, Late Ottawan (ca. 1035 Ma) hydrothermal signatures in the southeastern Adirondack Lowlands: New geochronological, stable isotope and fluid inclusion results: Geological Society of America Abstracts with Programs, v. 40(2), p. 61.

*Tubman, SC, Peck, WH, 2008 Carbon isotopes of maple syrup: A record of atmospheric and environmental change: Geological Society of America Abstracts with Programs, v. 40(2), p. 18.

*Tumpane, KP, and Peck, WH, 2006, Large carbon isotope fractionations in apatite: Geological Society of America Abstracts with Programs, v.38, n. 2, p. 26.