James M. DeGraff


Research Professor, Geological and Mining Engineering and Sciences

  • PhD, Geology, Purdue University
  • MS, Geophysics, Michigan Technological University
  • BS, Geology, Michigan Technological University


My goal is to make significant contributions to science and society by conducting and publishing geologic research in collaboration with other investigators, by training new scientists, and by communicating the meaning and value of science to the public.

I began my education at Michigan Tech and have a strong attachment to the area.  Here I learned to combine geological and geophysical methods to understand  geologic structures and to extrapolate this knowledge to the subsurface.  Afterward, I spent three years with the Peace Corps teaching applied geophysics, field geology, and independent studies at the Universidad Nacional de Asunción in Paraguay, and assisting a government agency to drill water wells for small rural communities.  While at Purdue, I focused on fracture processes in volcanic rocks during cooling and solidification, and developed thermal and rock mechanical skills to model formation of fracture networks based on measurements throughout the western USA.

My career has been mostly in the hydrocarbon industry with ExxonMobil in Houston, Texas.  During that time, I focused on geologic aspects of fracture reservoirs, traveling widely to work on these challenging reservoirs and collaborating with reservoir engineers to understand how fracture networks affect fluid flow.  Technical activities included core description, image-log interpretation, outcrop description, seismic interpretation, drilling data, statistical data analysis, and prospect assessment to determine the value of hydrocarbon accumulations and how to develop them.  Later I led small teams in applied research and advised work groups about appropriate data, technology, and methods to address reservoir issues.

I am pleased and excited to return to the university where I started and to contribute to the excellent work that is done here.

Research Interests

  • Structure and tectonics of the Midcontinent Rift System
  • Structural discontinuity formation in the shallow crust
  • Relative and absolute timing of rock deformation events
  • Fractured reservoir characterization, analysis, and modeling
  • Fluid flow through single fractures and fracture networks
  • Automated acquisition and analysis of geologic data from the Earth’s surface and drill core


  • Ibrayev, F., Fernandez-Ibanez, F., DeGraff, J.M., and Kussaiyn, A., 2016, Using a genetic-based approach to enhance natural fracture characterization in a giant carbonate field (North Caspian): SPE Annual Caspian Technical Conference & Exhibition, SPE-182565-MS, 16 p.
  • Lu, C.P., Wang, D., Johns, M., Murray, T., Heiney, S., DeGraff, J., and Gomez, L., 2009, A field study of azimuthal seismic anisotropy in fractured carbonates at Canyon Lake, central Texas: The Leading Edge, v. 28, no. 11, pp. 1322-1332.
  • Comin-Chiaramonti, P., Cundari, A., DeGraff, J.M., Gomez, C.B., and Piccirillo, E.M., 1999, Early Cretaceous-Tertiary magmatism in eastern Paraguay (western Paraná basin): geological, geophysical and geochemical relationships: Journal of Geodynamics, v. 28, no. 4-5, p. 375-391.
  • DeGraff, J.M. and Aydin, A., 1993, Effect of thermal regime on growth increment and spacing of contraction joints in basaltic lava; J. Geophys. Res., v. 98, no. B4, p. 6411-6430.
  • DeGraff, J.M., Long, P.E., and Aydin, A., 1989, Use of joint-growth directions and rock textures to infer thermal regimes during solidification of basaltic lava flows; J. Volcanol. Geotherm. Res., v. 38, p. 309-324.
  • Aydin, A. and DeGraff, J.M., 1988, Evolution of polygonal fracture patterns in lava flows; Science, v. 239, p. 471-476.
  • DeGraff, J.M. and Aydin, A., 1987, Surface morphology of columnar joints and its significance to mechanics and direction of joint growth; Geol. Soc. Amer. Bull., v. 99, p. 605-617.
  • DeGraff, J.M., Franco, R., and Orue, D., 1981, Interpretación geofísica del Valle de Ypacaraí (Paraguay) y su formación; Rev. Asoc. Geol. Argentina, v. 36, no. 3, p. 240-256.