Department of Geosciences

School of Natural Sciences and Mathematics

Faculty and Research

Emile A. Pessagno, Jr.


B.A., Geology, Princeton University, 1955
M.S., Geology, Cornell University, 1957
Ph.D., Princeton University, 1960

Research Interests

My research during the past three decades has focused on the study of two groups of planktonic microfossils: the Radiolaria and planktonic Foraminifera. Moreover, the fruit of these investigations has been to utilize radiolarian and planktonic foraminiferal biostratigraphic, chronostratigraphic, and paleobiogeographic data to solve complex geologic problems.

In that my research has established that radiolaria can be recovered from chert and limestone exposed to greenschist facies metamorphism to garnet mica-schist metamorphism, it is obvious that the stratigraphic utility of the Radiolaria extends far beyond that of other Mesozoic microfossils. During the past thirty years my students and I have developed a radiolarian zonation for the Mesozoic (Upper Triassic to Upper Cretaceous) which has been well integrated with ammonite-based chronostratigraphic data.

Some of my most recent studies have dealt with the utilization of Radiolaria and other groups of fossils in tectonostratigraphic reconstructions. A colleague and myself were able to establish via physical stratigraphy and radiolarian paleobiogeography that the Caribbean Plate originated in the Pacific during the Late Jurassic.

Dissertations and Theses Supervised

Seyed Mohsen Kariminia, PhD, 2006.  Dissertation: Upper Jurassic and Lower Cretaceous radiolaria biostratigraphy of California coast ranges.

Dragana D. Nebregic, PhD, 2006.  Dissertation: Cenomanian-Turonian planktic foraminiferal bioevents during the time of global oceanic event II and maximum sea level rise, Western Interior Basin and and Texas Gulf Coast.

Arafat A. Al-Shuaibi, PhD, 2006.  Dissertation: Coniacian to lowermost Campanian stratigraphy of the Austin Chalk, Northeast Texas.

Mahmoud Salah El-Din Ragab, PhD, 2004.  Dissertation: Integrated palynology and sequence stratigraphy of the Upper Cretaceous (Maastrichtian) Strata, Rio Grande Embayment, Texas, using well, outcrop, and seismic data.

Edgar K. Cross, PhD, 2001.  Dissertation: Origin of phosphorite bearing deep-water remnants of the San Piedro del Gallo Terrane in northeastern Mexico.

Pamela A. Stephens, PhD, 2001.  Dissertation:  Foraminiferal analysis of sediment cores from Laguna Madre, Nueces Bay, the Arroyo Colorado and Laguna Atascosa: South Texas Coast.

Jeanne M. Holloway, PhD, 1999.  Dissertation: Lithostratigraphy and biostratigraphy of the Austin Chalk from San Antonio west to the Anacacho Mountains.

Edgar G. Cross, MS, 1999.  Thesis: Petrochemical, microfacies, and stratigraphic investigation of the Lower Oxfordian to Lower Berriasian successions at Canyon San Matias and Canyon Puertos Blanco, Zacatecas, Northeast Mexico.

Ignacio Pujana, PhD, 1997.  Dissertation: Investigation of Middle and Lower Jurassic Radiolaria from the Neuquen Basin of West-Central Argentina.

Xiangming Meng, PhD, 1997.  Dissertation: Radiolarian biostratigraphy of the Upper Jurassic strata of the San Pedro del Gallo Terrane, north-central Mexico, and the Lower Cretaceous strata of the Nooksack Group, Nooksack Terrane, Northwestern Washington.

Christopher B. Martin, MS, 1996.  Thesis: Tectonostratigraphic analysis of the Upper Jurassic through Lower Cretaceous in the Mazapil, Sierra de Jimulco, and San Petro del Gallo regions of north-central Mexico.

Jamie M. Graham, PhD, 1995.  Dissertation: Lithostratigraphy, microfacies and foraminiferal biostratigraphy of the Santonian-Lower Campanian strata in the Trans-Pecos region, West Texas.

Yi Tang, MS, 1994.  Thesis: Systematic study on the radiolarian genus Higumastra from the Snowshoe Formation, John Day Inlier, east-central Oregon.

Ignacio Pujana, MS, 1993.  Thesis: Middle Jurassic (Bathonian-Calovian) radiolaria from Chacay Melehue, Cardillera del Viento, Province of Neuquen, Argentina.

Ivette Muñoz, MS, 1993. Thesis: Jurassic radiolarian Biostratigraphy of Volcanopelagic Strata overlying the Cuesta Ridge Remnant of the Coast Range Ophiolite.

Donna M. Hull, PhD, 1991.  Dissertation: Upper Jurassic radiolarian biostratigraphy of the lower member of the Taman Formation, east-central Mexico, and of volcanopelagic strata overlying the coast range ophiolite, Stanley Mountain, southern California Coast Ranges.

Jon A. Schwartzapfel, PhD, 1990.  Dissertation: Biostratigraphic investigations of Late Paleozoic (Upper Devonian to Mississippian) radiolaria within the Arbuckle Mountains and Ardmore Basin of south-central Oklahoma.

Brad E. Robinson, MS, 1990.  Thesis: Upper Triassic radiolarian biostratigraphy of the Glenn Shale, east-central Alaska.

Qun Yang, PhD, 1988. Dissertation: Upper Jurassic (Upper Tithonian) Radiolaria from the Taman Formation, east-central Mexico

Christopher Lee Garey, MS, 1987. Thesis: Radiolaria from the Otter Point Complex ( Oregon ) and the volcano-pelagic strata above the Coast Range ophiolite ( California ).

Norman MacLeod, PhD, 1986. Dissertation: Systematic, phylogenetic and morphometric analysis of the Jurassic radiolarian Genus Perispyridium Dumitrica.

Victor M. Davila-Alcocer, MS, 1986. Thesis: Upper Jurassic, Lower/Upper Cretaceous radiolarian biostratigraphy of the Eugenia and Asuncion Formations, from the Vizcaino Peninsula, Baja California Sur, Mexico.

Patricia Ann Whalen, PhD, 1985. Dissertation: Lower Jurassic radiolarian biostratigraphy of the Kunga Formation, Queen Charlotte Islands, British Columbia and the San Hipolito Formation, Baja California Sur.

Kuei-Yu Yeh Cheng, PhD, 1985. Dissertation: Taxonomic Studies of Lower Jurassic Radiolaria from the Nicely Formation, the Hyde Formation and the Snowshoe Formation, east-central Oregon

Yen-Nien Cheng, PhD, 1985. Dissertation: Upper Paleozoic (Upper Devonian and Carboniferous) Radiolaria from the Ouachita Mountains, Oklahoma and Arkansas.

Thompson, Laird Berry, PhD, 1983. Dissertation: The Campanian Shelf in northeast Texas

Sandra Lee Nash, MS, 1982. Thesis: Taxonomic and phylogenetic studies on five genera in the Heterohelicidae.

Karen M. Morin, PhD, 1982. Dissertation: Analysis and definition of Campanian (Late Cretaceous) radiolarian populations characteristic of tropical to subtropical latitudes.

Phyllis R. Tippit, PhD, 1981. Dissertation: The biostratigraphy and taxonomy of Mesozoic Radiolaria from the Samail Ophiolite and Hawasina Complex, Oman.

Charles David Blome, PhD, 1981. Dissertation: Upper Triassic Radiolaria from eastern Oregon and British Columbia.

Malana Langston, MS, 1979. Thesis: Radiolarian biostratigraphy of cherts associated with ophiolites in the California Coast Ranges.

Lawrence S. Levy, MS, 1977. Thesis: Radiolarian biostratigraphy of the Marca Shale Member, Moreno Formation, Fresno County, California.

Barbara Helen Keating, MS, 1975. Thesis: Biostratigraphy and magnetostratigraphy of Late Cretaceous sediments.

Charles C. Smith, PhD, 1973. Dissertation: Calcareous nanoplankton and stratigraphy of the Upper Eagle Ford and Lower Austin Formations, Texas.

Jose Francisco Longoria-Trevino, PhD, 1972 (First graduate degree in Geosciences). Dissertation: Stratigraphic, morphologic and taxonomic studies of Aptian planktonic foraminifera.


Pessagno, E. A., Jr. "Faunal evidence for tectonic transport of Nevadan terranes in Western North America" in Geological Society of America Special Paper 410: Geological studies in the Klamath Mountains Province, California and Oregon : A volume in honor of W. P. Irwin, ed. by A.W. Snoke and C.G. Barnes. U.S. Geological Survey, Menlo Park, California, in press.

Hopson, C. A. and Pessagno, E. A., Jr. "Tehama-Colusa Serpentinite Mélange: A remnant of Franciscan Jurassic oceanic lithosphere, Northern California " in Serpentine and serpentinites: Mineralogy, petrology, geochemistry, ecology, geophysics, and tectonics, ed. by Robert G. Coleman. Geological Society of America Book Series, vol. 8, p. 301-336, in press.

Miller, M. L., Bradley, D. C., Bradley, Bundtzen, T. K., Blodgett, R. B., Pessagno, E. A., Jr., Tucker, R. D., and Harris, A. G.
"The restricted Gemuk Group, a Triassic to Early Cretaceous succession in southwest Alaska." Geological Society of America Special Volume, ed. by K. Ridway, in press.

Pessagno, E. A., Jr., Mattinson, J. M., Montgomery, H., and Hopson, C. A. "Geochronological significance of new biostratigraphic, chronostratigraphic, and geochronometric data from La Désirade, Lesser Antilles." In Ophiolites, arcs, and batholiths: A Geological Society of America Special Paper in honor of C. A. Hopson, ed. by J. Wright and J. Shervais. Dept of Geological Sciences, University of California, Santa Barbara, submitted 2006.

Cross, E. and Pessagno, E. A., Jr. "Tectonostratigrahy and Depositional Environments within Upper Jurassic Phosphate-Bearing Remnants of the San Pedro del Gallo Terrane Northeastern Mexico." Submitted to Stratigraphy (2005).

Pessagno, E. A., Jr., Ghazi, A. M., Kariminia, M., Duncan, R. A., and Hassanipak, A. "A.Tectonostratigraphy of Khoy Complex, Northwestern Iran." Stratigraphy 2 (2005) 1-22 & 49-63.

Hopson, C. A. and Pessagno, E. A., Jr. "Tehama-Colusa Serpentinite Mélange: A remnant of Franciscan Jurassic oceanic lithosphere, Northern California." International Geology Review 47 (2005) 65-100.

Pessagno, E. A., Jr. and Martin, C. "Tectonostratigraphic evidence for the origin of the Gulf of Mexico." In The Circum-Gulf of Mexico and the Caribbean : Hydrocarbon habitats, basin formation, and plate tectonics, ed. by C. Bartolini, R.T. Buffler and Blickwede. AAPG Memoir 79 (2003) 46-74.

Pessagno, E. A., Jr. and Hull, D. M. "Upper Jurassic (middle Oxfordian) Radiolaria from the Sula Islands ( East Indies ): Their taxonomic, biostratigraphic, chronostratigraphic, and paleobiogeographic significance." Micropaleontolgy 48 (2002) 229-256.

Pessagno, E. A., Jr., Hull, D. M., and Hopson, C. A. "Tectonostratigraphic significance of sedimentary strata occurring within and above the Coast Range Ophiolite (California Coast Ranges) and the Josephine Ophiolite (Klamath Mountains, Northwestern California)." In Ophiolites and Oceanic Crust: New Insights from Field Studies and Ocean Drilling Program, ed. by Y. Dilik, et. al. Geological Society of America Special Paper 349 (2001) 383-394.


Invited to be plenary speaker at Interrad XI Conference: Radiolarians in stratigraphy and paleoceanography: 11th Meeting of International Association of radiolarian paleontologists and Circum-Pacific Triassic Stratigraphy and Correlation, a symposium hosted by IGCP 467 and STS. Wellington, New Zealand, March 2006.

Editor of journal Stratigraphy. Accepted editorship October 2005. January 1, 2006 to present.

Co-Founder and Chairman, Editorial Board of new Stratigraphy, Micropaleontology Press, 2003 to present.

Voting Member of International Subcommission on Jurassic Stratigraphy (R. Enay, Chairman). One of two U. S. representatives, 1984 to present.

Founder and President of North American Micropaleontology Section, S. E. P. M., 1977-1979. Past President 1980-1981.

Past President of Councilor North American Micropaleontology Section, S. E. P. M., 1979-1980.

Member of Biostratigraphic Panel ( Deep Sea Drilling Project), 1967-1975.

Member of Board of Directors of Cushman Foundation for Foraminiferal Research, 1967-present.

  • Updated: July 27, 2007