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Phone: 979.845.9828
Fax: 979.845.6331
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Texas A&M University
O&M Building, Room 317A
MS 3146,
College Station, Texas 77843

Course Offerings:

  • OCNG 630 - Geological Oceanography
  • OCNG 681 - How to Write and Publish a Scientific Paper
  • OCNG 666 - Principles of Geodynamics
  • OCNG 689-601 - Special Topics in High-resolution Seafloor Mapping

Dr. William Sager

Professor Oceanography and G&G, Jane and R. Ken Williams '45 Chair in Ocean Drilling Science, Technology and Education

Ph.D. Marine Geophysics, University of Hawaii, 1983

M.S. Geology and Geophysics, University of Hawaii, 1979

B.S. Physics, Duke University, 1976


Dr. Sager’s research is broadly about Earth history, plate tectonics, and the evolution of ocean basins. He is a marine geophysicist who loves to explore the ocean and has been on 38 research cruises and was chief scientist on 17 of them. He has participated on seven Ocean Drilling Program cruises and was co-chief scientist for two. His expeditions have taken him and his students to each of the big three oceans. Current research efforts are concentrated on geophysical studies of hotspots and ocean plateaus and how they formed and evolved as well as magnetic anomaly interpretations and the geomagnetic polarity reversal time scale. Dr. Sager has also published numerous papers about paleomagnetic measurements and their interpretations for plate tectonics, especially for the Pacific plate apparent polar wander path. He is also interested in high-resolution marine geophysics, using sonars and other sensors to study the seafloor, and the geologic development of the shelf and continental margins, especially in the Gulf of Mexico.

Dr. Sager has published over 90 refereed articles in journals and books. He has won more than 40 research grants totaling nearly $4.5 M. He received the College of Geosciences Award for Distinguished Achievement in Research in 2003 and became the first holder of the Jane and R. Ken Williams ’45 Chair in Ocean Drilling Science, Education, and Technology that same year.

Research Interests

  • Plate tectonics
  • Tectonic reference frames
  • Paleomagnetism and environmental magnetism
  • Magnetostratigraphy and the magnetic polarity reversal time scale
  • Pleistocene-Holocene sea level variations
  • High-resolution geophysical methods
  • Magnetic and gravity field interpretation


  • Geophysical study of Ninetyeast Ridge hotspot trail in the Indian Ocean
  • Study of multichannel seismic data from the Northwest Gulf of Mexico and their implications for the structure of continental margin and indicatinos of gas hydrate
  • Testing hypotheses of oceanic plateau formation on Shatsky Rise.
  • High-resolution geophysical studies of Gulf of Mexico shelf and slope sediments and sedimentary deformation.
  • Magnetic field behavior of the Jurassic Magnetic Quiet Zone.
  • Paleomagnetism of ocean crust basalts.


  • Professor, Oceanography, Texas A&M University, 1995–present
  • Associate Professor, Oceanography, Texas A&M University, 1989–1995
  • Assistant Professor, Oceanography, Texas A&M University, 1983–1989
  • Participant on 37 research cruises since 1977, including 16 as chief scientist.
  • Co-chief scientist on ODP Legs 143 and 191


  • Sager, W. W. Divergence between paleomagnetic and hotspot model predicted polar wander for the Pacific plate with implications for hotspot fixity, in Plates, Plumes, and Planetary Processes, Special Paper 430, G. R. Foulger and D. M. Jurdy, eds., Boulder, Colorado, Geological Society of America, pp. 335-359, 2007.
  • Beaman, M., W. W. Sager, G. D. Acton, L. Lanci, and J. Pares. Improved Late Cretaceous and early Cenozoic Paleomagnetic apparent polar wander path for the Pacific plate, Earth and Planetary Science Letters, 262, 1-20, 2007.
  • Tivey, M. A., W. W. Sager, S. M. Lee, and M. Tominaga. Rapid magnetic field reversal and low amplitude as cause of the Pacific Jurassic Quiet Zone, Geology, 34, 789-792, 2006.
  • Sager, W. W. Cretaceous Basalt Core Paleomagnetic Poles for the Pacific Plate: Implications for Apparent Polar Wander and Plate Tectonics, Phys. Earth Planet. Int., 156, 329-349, 2006.
  • Sager, W. W. What Built Shatsky Rise, a Mantle Plume or Ridge Tectonics? in Plates, Plumes, and Paradigms, Special Paper 388, G. R. Foulger, J. H. Natland, D. C. Presnall, and D. L. Anderson (Eds.), Geological Society of America, Boulder, CO, pp. 721-733, 2005.
  • Sager, W. W. A Chron. 33r Paleomagnetic Pole for the Pacific Plate, Geophys. Res. Lett., 30, doi: 10.1029/2003GLO17964.
  • Sager, W.W., I. R. MacDonald and R. Hou. Side Scan Sonar imaging of hydrocarbon seeps on the Louisiana continental slope, Amer. Assoc. Petrol. Geol. Bull. 88, 725-746, 2004.
  • Sager, W.W., and B. Horner-Johnson. Paleomagnetism of basaltic rocks cored at ODP Site 1179: Implications for paleolatitude and the mid-cretaceous plaleomagnetic pole, Proc. ODP, Sci. Res. 191, in press.
  • Sager, W. W., I. R. MacDonald, and R. Hou. Geophysical signatures of mud mounds at hydrocarbon seeps on the Louisiana continental slope, northern Gulf of Mexico, Marine Geology, 198, 97-132, 2003.
  • Sager, W. W. Basalt Core Paleomagnetic Data from Detroit Seamount, Northern Emperor Seamount Chain, and Implications for the Paleolatitude of the Hawaiian Hotspot, Earth Planet. Sci. Lett., 199, 347-358, 2002.
  • Sager, W. W. and A. A. P. Koppers. Late Cretaceous polar wander of the Pacific plate: evidence of a true polar wander event, Science, 287, 455-459, 2000.
  • Sager, W. W., J. Kim, A. Klaus, M. Nakanishi, and L. M Khankishieva. Bathymetry of Shatsky Rise, Northwest Pacific Ocean: Implications for Ocean Plateau Development at a Triple Junction, J. Geophys. Res., 104, 7557-7576, 1999.
  • Nakanishi, M., W. W. Sager, and A. Klaus, Magnetic lineations within Shatsky Rise, northwest Pacific Ocean : Implications for hot spot-triple junction interaction and oceanic plateau formation, J. Geophys. Res., 104, 7539-7556, 1999.
  • Sager, W. W., W. W. Schroeder, K. S. Davis, and R. Rezak. A Tale of Two Deltas: Seismic Mapping of Near Surface Sediments on the Mississippi-Alabama Outer Shelf and Implications for Recent Sea Level Fluctuations, Mar. Geol., 160, 119-136, 1999.
  • Sager, W. W., C. S. Lee, I. R. Macdonald, and W. W. Schroeder. High-frequency near-bottom acoustic reflection signatures of hydrocarbon seeps on the northern Gulf of Mexico continental slope, Geo-Mar. Lett., 18, 267-276, 1999.
  • Sager, W.W., C.J. Weiss, M. Tivey, and H.P. Johnson. Geomagnetic Polarity reversal model of deep-tow profiles from the Pacific Jurassic 'Quiet Zone'," J. Geophys. Res., 103, 5269-5286, 1998.

Edited Books and Volumes

  • Special Issue: High Resolution Mapping of Continental Margin Geohazards, Amer. Assoc. Petrol. Geol. Bull., edited by W. Sager, W. Bryant, and E. Doyle, June 2004.
  • Proceedings of the Ocean Drilling Program, Initial Reports, vol. 191, T. Kanazawa, W. W. Sager, C. Escutia, et al. (Eds.), Ocean Drilling Program, College Station, TX, 2001.
  • Proceedings of the Ocean Drilling Program, Scientific Results, vol. 143, W. W. Sager, W. L. Winterer, J. Firth, and J. Sinton (Eds.), Ocean Drilling Program, College Station, TX, 1995.
  • The Mesozoic Pacific: Geology, Tectonics, and Volcanism. M.S. Pringle, W. W. Sager, W. V. Sliter, and S. Stein (Eds.) Monograph 77, American Geophysical Union , Washington DC, 1993.
  • Proceedings of the Ocean Drilling Program, Initial Reports, vol. 143, E. L. Winterer, W. W. Sager, J. Firth, et al. (Eds.), Ocean Drilling Program, College Station, TX, 1992.
  • Proceedings of the Ocean Drilling Program, Scientific Results, vol. 116, J. Cochran, D. V. Stowe, W. W. Sager, et al. (Eds.), Ocean Drilling Program, College Station, TX, 1990.
  • Proceedings of the Ocean Drilling Program, Initial Reports, vol. 116, D. V. Stowe, J. Cochran, W. W. Sager, et al. (Eds.), Ocean Drilling Program, College Station, TX, 1989.
  • Paleomagnetic Constraints on Crustal Motions, W. W. Sager (Ed.) Tectonophysics, v. 182, no. 3/4, 1990. Mesozoic and Cenozoic Plate Reconstructions, C. Scotese and W. Sager (Eds.) Tectonophysics, v. 155, no. 4, 1988.
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