Associate Professor Mark A. Kleffner 419-995-8208, kleffner.1@osu.edu
Department of Geological Sciences - Ohio State University at Lima
4240 Campus Drive, Lima, Ohio 45804-3576

Education

1979-1988	Master of Science and Doctor of Philosophy in geology with an emphasis on paleontology/paleobiology and stratigraphy, The Ohio State University,  Columbus, Ohio (Walter C. Sweet, advisor)
1975-1979	Bachelor of Science in geology (cum laude) with 67 hours in geology and 20 hours in biological sciences, The Ohio State University, Columbus, Ohio (Walter C. Sweet, advisor)

Publications (* refereed paper or abstract, # presented at meeting)

 Kleffner, M. A., Barrick, J. E., and Tychsen, A. 2004. *#Conodont-, graptolite-, and chitinozoa-based Silurian composite developed using graphic correlation aids new calibration of current Silurian chronostratigraphy [abs.] Geological Association of Canada, Mineralogical Association of Canada 2004 Joint Annual Meeting Abstracts Volume (ISBN 0-919216-97-8), p. 96 (I was responsible for 90% of the content, 100% of the preparation, and I gave the presentation at the conference.)

Kleffner, M. A., and Larsen, G. E. 2003.*#Bass Islands Identity Crisis and a Possible Solution [abs.] The Ohio Journal of Science, 103(1):21 (I was responsible for 50% of the content, 100% of the preparation, and I gave the presentation at the conference.)

Kleffner, M. A., and Murphy, M. A. 2003. *#Lower Silurian conodonts of central Nevada and their stratigraphic significance [abs.] The Geological Society of America Abstracts with Programs, 35(2):5 (I was responsible for 90% of the content, 80% of the preparation, and I gave the presentation at the conference.)

Kleffner, M. A. 2002.*#Conodont events of the late Llandovery (Silurian) through earliest Devonian of the North American Midcontinent [abs.] The Geological Society of America Abstracts with Programs, 34(2):A101.

Kleffner, M. A., and Barrick, J. E. 2002.*#Newly revised and calibrated conodont-, graptolite-,

and chitinozoa-based Silurian chronostratigraphy developed using the graphic correlation method [abs.] The Geological Society of America Abstracts with Programs, 34(2):A27. (I was responsible for 90% of the content, 100% of the preparation, and I gave the presentation at the conference.)

Kleffner, M. A. 2001.*# Do Aimitation@ and Abent@ Brassfield and diachronous Dayton indicate Ohio=s Lower Silurian Alayer-cake@ stratigraphy is half-baked? [abs.] Ohio Journal of Science 101(1):A24.

Kleffner, M. A., and Barrick, J. E. 2001. *#A conodont-, graptolite-, and chitinozoa-based Silurian (upper Llandovery-Pridoli) chronostratigraphy [abs.] The Geological Society of America Abstracts with Programs, 33(4):A20. (I was responsible for 90% of the content, 100% of the preparation, and I gave the presentation at the conference.)

Kleffner, M. A.,  and Rexroad, C. B., 2000, *#A quantitative conodont biostratigraphy for the Salamonie Dolomite and the Salina Group (Silurian) of the northern Indiana subsurface (abs.). Ohio Journal of Science, 100(1):A10-11. (I was responsible for 95% of the

content,  100% of the preparation, and I presented the poster session.)

Kleffner, M. A., 2000, *#Conodont biostratigraphy, sequence stratigraphy, and oceanic event record of the Noland Formation and Estill Shale (Lower Silurian) of southern Ohio (abs.). The Geological Society of America Abstracts with Programs, 32.

Kleffner, M. A., 2000, Lower Silurian (Llandovery-Wenlock) stratigraphy of west-central Ohio. Geology Field Trip for The Ohio Academy of Science 109^th Annual Meeting, Ada, Ohio, March 31-April 2, 2000, 12 p.

Kleffner, M. A., and Rexroad, C. B., 1999. *#Preliminary conodont biostratigraphy of the Salina Group (Silurian) of the northern Indiana and recognition of the Wenlock/Ludlow boundary (abs.). American Association of Petroleum Geologists Eastern Section Twenty-Eighth Annual Meeting Program with Abstracts, p. 33-34. (I was responsible for 90% of the content, 100% of the preparation, and I presented the poster session.)

Kleffner, M. A., Norby, R. D., Kluessendorf, J., and Mikulic, D. G., 1999. *#Lower Silurian conodont biostratigraphy of southeastern Wisconsin (abs.). The Geological Society of America Abstracts with Programs, 31(5):A28. (I was responsible for 80% of the content and 95% of the preparation. I presented the paper.)

Kleffner, M. A., 1998, *#Wenlock conodont chronostratigraphy and sequences of the Appalachian Basin in New York, Ohio, and Tennessee [abs.], American Association of Petroleum Geologists 27th Annual Eastern Section Meeting Program with Abstracts, p. 48.

Kleffner, M. A., and Barrick, J. E., 1998, *#A revised Silurian chronostratigraphy: conodont and graptolite chronozonation and a calibrated Wenlock-Pridoli time scale [abs.], Geological Society of America Abstracts with Programs, 30(2):28. (I was responsible for 90% of the content and preparation, and I presented the paper.)

Kleffner, M. A., and Barrick, J. E., 1997, *#Ozarkodina sagitta and revision of a conodont‑ and graptolite‑based Silurian composite standard developed by graphic correlation [abs.], Geological Society of America Abstracts with Programs, 29(2):17‑18. (I was responsible for 90% of the content and preparation, Jim presented the paper.)

Kleffner, M. A., 1997, *#Silurian (Llandovery‑Wenlock) conodont chronostratigraphy and correlation of Cincinnati Platform and distal Appalachian Basin strata, southern Ohio [abs.]. The Ohio Journal of Science, 97(2):A21.

Kleffner, M. A., and Barrick, J. E., 1996, *#Development of a North American southern midcontinent Silurian (Upper Llandovery-Wenlock) composite, correlation with a global Silurian composite, and implications for Wenlock conodont zones and conodont phylogeny, [abs.]. In J. E. Repetski (ed.), Abstracts of Papers, Sixth North American Paleontological Convention, Smithsonian Institution, Washington, D.C. Paleontological Society Special Publication 8:221. (I was responsible for 60% of the content, 90% of the preparation, and I presented the paper.)

Kleffner, M. A., and Barrick, J. E., 1996, *#A revised conodont- and graptolite-based Silurian chronostratigraphy developed by graphic correlation, [abs.] The James Hall Symposium: Second International Symposium on the Silurian System, Program and Abstracts, p. 64. (I was responsible for 80% of the content and preparation. Jim presented the paper.)

Kleffner, M. A. 1996. *Conodonts and sequences of the Silurian Appalachian foreland basin [abs.]. Geological Society of America Abstracts with Programs, 28(3):73.

Norby, R. D., Mikulic, D. G., Kluessendorf, J., and Kleffner, M. A., 1996, *#Silurian conodont biostratigraphy of the Lake Michigan area, [abs.] The James Hall Symposium: Second International Symposium on the Silurian System, Program and Abstracts, p. 78. (I was responsible for 40% of the content and 25% of the preparation.  Rod presented the paper)

Kleffner, M. A., 1995, *A conodont- and graptolite-based Silurian chronostratigraphy. In Mann, K. and Lane, H. R., (eds.) Graphic Correlation. SEPM Society for Sedimentary Geology Special Publication No. 53, p. 159-176. Tulsa, OK.

--------, 1995, *#Silurian chronostratigraphy and development of a Silurian time scale by graphic correlation, [abs.] GSA Abstracts with Programs, 27(3):64.

Kleffner, M. A., Norby, R. D., Kluessendorf, J., and Mikulic, D. G., 1995, *#Conodont distribution and preliminary conodont chronostratigraphy of Lower Silurian strata in southeastern Wisconsin, [abs.] GSA Abstracts with Programs, 27(3):65. (I was responsible for 80% of the content and 75% of the preparation. I also presented the paper.)

Kleffner, M. A., 1994, A conodont- and graptolite-based Silurian chronostratigraphy and development of a Silurian time scale by graphic correlation, SEPM Research Conference-Graphic Correlation and the Composite Standard: the Methods and Their Applications, Abstracts Volume, unpaginated.

--------, 1994, *Conodont biostratigraphy and depositional history of strata comprising the Niagaran sequence (Silurian) in the northern part of the Cincinnati Arch region, west-central Ohio, and evolution of Kockelella walliseri (Helfrich), Journal of Paleontology, 68(1):141-153.

--------, 1994, *#Conodont biostratigraphy of Ludlow boundary stratotype sections, [abs.] GSA Abstracts with Programs, 26(5):23.

Kleffner, M. A., Norby, R. D., Kluessendorf, J., and Mikulic, D. G., 1994, *Conodont biostratigraphy of the Brandon Bridge and associated Silurian Waukesha lagerstatte in Waukesha County, Wisconsin, [abs.] GSA Abstracts with Programs, 26(5):23. (I was responsible for 70% of the content and 75% of the preparation. Rod presented the paper.)

Kleffner, M. A., 1993, *#Conodonts of the Salina Group (Silurian) in the North American midwestern basins and arches region, [abs.] GSA Abstracts with Programs, 25(3):31.

--------, 1993, *#A revised conodont- and graptolite-based Silurian chronostratigraphy, [abs.] GSA Abstracts with Programs, 25(2):30.

--------, 1992, *#Conodonts and their implications concerning the Lockport/Salina contact in the

North American midwestern basins and arches region, [abs.] GSA Abstracts with Programs, 24(7):319-320.

--------, 1992, *#Recognition of the Wenlock/Ludlow boundary in regions with and without graptolite-bearing strata, [abs.] GSA Abstracts with Programs 24(4):26.

--------, 1991, *#Evolution and distribution of Wenlockian (Silurian) conodonts (excluding coniforms) in North America following the early Wenlockian extinction event, [abs.] Canadian Paleontology Conference I Program and Abstracts, p.44.

--------, 1991, *#The Clinton Group (Silurian) of western New York: conodonts, correlation, and unconformities, [abs.] GSA Abstracts with Programs, 23(3):22.

 --------, 1991, *Conodont biostratigraphy of the upper part of the Clinton Group and the Lockport Group (Silurian) in the Niagara Gorge region, New York and Ontario, Journal of Paleontology, 65(3):500-511.

Kleffner, M. A., and Riddle, S. W., 1990, *#Foerste's forgotten formation, the Lower Silurian Centerville Formation of Ohio, [abs.] The Ohio Journal of Science, 90(2):12. (I was responsible for 60% of the content and 80% of the preparation. I presented the paper.)

Kleffner, M. A., 1990, *Wenlockian (Silurian) conodont biostratigraphy, depositional environments, and depositional history along the eastern flank of the Cincinnati Arch in southern Ohio, Journal of Paleontology 64(2):319-328.

Kleffner, M. A., 1989, *A conodont-based Silurian chronostratigraphy, Geological Society of America Bulletin, 101:904-912.

Kleffner, M. A., 1989, *#Conodonts and chronostratigraphy of the upper Clinton and Lockport Groups (Silurian) in western New York and adjacent Ontario, Canada, [abs.] GSA Abstracts with Programs 21(4):18.

Kleffner, M. A., Riddle, S. W., Bergman, C. F., Hart, C. P., and Bauer, J. A., 1989, *#Ordovician-Silurian boundary strata in the Cincinnati Arch region: microfossils and their implications for stratigraphy, eustasy, and tectonics, [abs.], GSA Abstracts with Programs 21(6). (I was responsible for 40% of the content and 75% of the preparation. I presented the paper.)

Kleffner, M. A., 1988, *#Lilley Formation, Lilley-Peebles transition unit, and Peebles Dolomite (Silurian, southern Ohio): conodont biostratigraphy and chronostratigraphy and depositional history, [abs.] GSA Abstracts with    Programs 20(5): 351.

Kleffner, M. A., and Ausich, W. I., 1988, Lower and Middle Silurian of the eastern flank of the Cincinnati Arch and the Appalachian Basin margin, Ohio, 1988 SEPM Midyear Meeting field trip guide, 25 p. (I was responsible for 60% of the content and 90% of the preparation.)

Miller, M. A., Brett, C. E., and Kleffner, M. A., 1988, *Ludlow age acritarchs and spores from the Pittsford Shale, New York, [abs.] American Association of Stratigraphic Palynologists 21st Annual Meeting Program and Abstracts, November 10-12, 1988, unpaginated. (I was responsible for 25% of the content. Merrell presented the paper.)

Kleffner, M. A., 1987, *Conodonts of the Estill Shale and Bisher Formation (Silurian, southern Ohio): biostratigraphy and distribution, The Ohio Journal of Science 87(3): 78-89.

--------, Leatham, W. B., and Sweet, W. C., 1987, *Ordovician ancestors for Silurian conodonts, [abs.] GSA Abstracts with Programs 19(3): 171. (I was responsible for 40% of the content and 50% of the preparation. Britt presented the paper.)

Kleffner, M. A., 1987, *#A Silurian chronostratigraphic scale based on conodont and graptolite ranges, [abs.] GSA Abstracts with Programs 19(7): 728-729.

--------, 1986, *#Restudy of conodonts from Silurian strata of the Niagara Gorge, [abs.] GSA Abstracts with Programs 18(3): 250.

--------, 1986, *Silurian (Llandovery-Ludlow) conodont biostratigraphy of west-central Ohio and its bearing on correlation, [abs.] GSA Abstracts with Programs 18(4): 313.

--------, 1985, *#Conodont biostratigraphy of the "Packer Shell" (Silurian, Ohio subsurface), [abs.] GSA Abstracts with Programs 17(2): 98.

--------, 1985, *#The Lilley Formation (Silurian, Ohio): conodont biostratigraphy and correlation with Silurian formations of the Great Lakes Region, [abs.]  GSA Abstracts with Programs 17(5): 296.

--------, 1985, *#A conodont-based Silurian chronostratigraphy, [abs.] GSA Abstracts with Programs 17(7): 629.

Kleffner, M. A., 1985, *Conodont biostratigraphy of the Stray "Clinton" and "Packer Shell"(Silurian, Ohio subsurface) and its bearing on correlation, in Gray, J., Maslowski, A., McCullough, W., and Shafer, W. E., (eds.) The New Clinton Collection-1985, Columbus, Ohio, Ohio Geological Society, p. 219-229.

Kleffner, M. A., 1984, *#Conodonts of the Silurian Estill Shale and Bisher Formation in southern Ohio and their bearing on the Estill-Bisher contact and depositional environment, [abs.] GSA Abstracts with Programs 16(3): 150.

Rexroad, C. B. and Kleffner, M. A., 1984, The Silurian stratigraphy of east-central Kentucky and adjacent Ohio, in Rast, N. and Hay, H. B., (eds.) Field Guides for GSA Annual Meeting, Southeastern and North-Central Sections, Dept. Geol. Univ. Kentucky and Kentucky Geol. Survey, Lexington, p. 44-64. (I was responsible for 30% of the content.)

Funded Research Projects

Taxonomy and biostratigraphic significance of Wenlockian and Ludlovian (Silurian) conodonts in the Midcontinent outcrop area, North America, (The listed Principal Investigator was my advisor, Walter C. Sweet, whose name was of major importance in the project getting funded, however the project was my concept, I wrote the proposal, and I was responsible for all the work done on the research project, which was my dissertation) National Science Foundation, Award No. EAR-8307021, 7/1/84-6/30/87, $71,600

Development of a heavy-liquid separation lab for conodont studies, The Ohio State University Office of Research and Graduate Studies University Small Grant, 8/22/90-12/31/91, $935

Biostratigraphy, evolutionary history, and color and textural alteration of conodonts of the Upper Lower and Upper Silurian of the midwestern basins and arches region, North America, The Ohio State University Office of Research and Graduate Studies Seed Grant, 3/12/91-12/31/92, $15,600

Conodont biostratigraphy and correlation of Lower Silurian strata associated with the Waukesha biota, Subcontractor on National Science Foundation grant to Illinois Geological Survey (Donald Mikulic, Principal Investigator), 8/1/92-7/30/93, with a budget of $15,013 for my portion of the project.

Conodont biostratigraphy of Silurian global boundary stratotypes, The Ohio State University at Lima, Lima Campus Research Grant, 3/93-3/94, $1649

Silurian boundary stratotype sections, The Ohio State University at Lima, Lima Campus Research Grant, 6/94-6/95, $210 

Lower Silurian Waukesha strata, Wisconsin, and Wenlock/Ludlow boundary strata, New York, The Ohio State University at Lima, Lima Campus Research Grant, 1/95-1/96, $2242

Lower Silurian conodont biostratigraphy of Kentucky and Ohio, The Ohio State University at Lima, Lima Campus Research Grant, 2/01-6/02, $2420

A conodont-, graptolite-, and chitinozoa-based Silurian chronostratigraphy, The Ohio State University at Lima, Lima Campus Research Grant, 2/02-3/03, $850

Conodont biostratigraphy and δ13C chemostratigraphy for the Late Ordovician-Early Silurian of the North American Midcontinent, The Ohio State University at Lima, Lima campus Research Grant, 3/03-6/04, $2484

Conodont biostratigraphy and δ13C chemostratigraphy for the Late Silurian-Early Devonian of western New York State, The Ohio State University at Lima, Lima campus Research Grant, 3/03-6/04, $2497

Research Awards

Outstanding Scholar Award, The Ohio State University at Lima, 5/19/91

Current/Future Research

My research is focused on Silurian conodonts and Silurian stratigraphy, primarily in the Midcontinent outcrop area, North America.  I am presently actively involved in six projects: Lower Silurian of Ohio and Kentucky; a revised conodont-, graptolite-, and chitinozoa-based Silurian chronostratigraphy; 13C chemostratigraphy of Ordovician/Silurian boundary strata of the North American Midcontinent (with Stig Bergström); conodont biostratigraphy, oceanic episodes, and 13C chemostratigraphy of Silurian/Devonian boundary strata of Cherry Valley region, New York; oceanic episodes, 13C chemostratigraphy, and updated Homerian, Gorstian, and Ludfordian (Silurian) conodont biostratigraphy of North America;  Ireviken Event and post-Ireviken 13C excursion in Niagara region, New York (with Brad Cramer); and an integrated conodont, graptolite, and chitinozoa biostratigraphy for the Williamson Shale, Rochester, New York (with David Loydell and Gary Mullins). I received Lima campus research grants to help out with the first three projects listed.  I am working on a joint proposal concerning the fourth-listed project with a colleague at Texas Tech University (James Barrick) to submit to the National Science Foundation for its January 2005 deadline.   My plans for the future include completing all of the studies briefly summarized above, as well as continuing studies of Silurian conodonts and stratigraphy.