John McLennan

Associate Professor Chemical Engineering


Phone: 801-587-7925
Fax: 801-585-3540

Geomechanics related to exploration, drilling, completion, stimulation and production

Regional & Basin Experience

  • Worldwide

1980 Ph.D. in Civil Engineering (Rock Mechanics), University of Toronto

1976 M.A.Sc. in Civil Engineering (Soil Mechanics), University of Toronto

1974 B.A.Sc. in Geological Engineering, University of Toronto


  • Society of Professional Well Log Analysts

  • Society of Petroleum Engineers

  • American Rock Mechanics Association

McLennan, J.D., Carden, R.S., Curry, D., Stone, C.R. and Wyman, R.E.: Underbalanced Drilling Manual, Gas Research Institute, GRI 97/0236 (1997) Chicago, IL.

Mitlin, V.S., Lawton, B.D. and McLennan, J.D.: “Improved Estimation of Relative Permeability from Displacement Experiments,” paper SPE 39830 presented at the 1998 SPE International Petroleum Conference and Exhibition of Mexico, Villahermosa, Mexico, March 3-5.

Vasquez, A.R., Sanchez, M.S., McLennan, J.D., Guo, Q., Portillo, F., Poquioma, W., Blundun, M. and Mendoza, H.: “Mechanical and Thermal Properties of Unconsolidated Sands and its Application to the Heavy Oil SAGD Project the Tia Juana Field, Venezuela,” paper SPE 54009 presented at the 1999 SPE Latin American and Caribbean Petroleum Engineering Conference, Caracas, Venezuela, April 21-23.

McLennan, J.D., Medley, G. and Veatch, R.: Underbalanced Completion Guide A Technology Review, Gas Research Institute, GRI 00/0178 (2001), Chicago, IL.

McLennan, J.D. and Abou-Sayed, A.S.: “Some Advances in Near Wellbore Geomechanics,” paper SPE/ISRM 78194 to be presented at the SPE/ISRM 2002 Rock Mechanics Conference, Irving, Texas, October 20-23.

Palmer, I.D., Vorpahl, D.G., Glenn, J.M., Vaziri, H. and McLennan, J.D.: “A Recent Gulf of Mexico Cavity Completion,” SPE 86462, SPE International Symposium and Exhibition on Formation Damage Control, held in Lafayette, Louisiana, U.S.A., 18-20 February 2004.

Suarez-Rivera, R., Green, S.J., McLennan, J.D. and Bai. M.: “Effect of Layered Heterogeneity on Fracture Initiation in Tight Gas Shales,” SPE 103327-MS, SPE ATCE, 2006.

Nagel, N. and McLennan, J.D. (ed.): Cuttings Injection, SPE Monograph, in preparation.

McLennan, J.D., Gue, Q., Wang, C., Geehan, T., Martin, W., and Marquardt, J.: “A Laboratory Study on Increased Assurance and Understanding Storage Mechanisms of E&P Waste Injection into an Unconsolidated Formation,” SPE 111707, SPE International Conference on Health, Safety, and Environment in Oil and Gas Exploration and Production, 15-17 April 2008, Nice, France

McLennan, J.D., Green, S.J. and Bai, M.: “Proppant Placement During Tight Gas Shale Stimulation: Literature Review And Speculation,” ARMA 08-335, 42nd US Rock Mechanics Symposium and 2nd U.S.-Canada Rock Mechanics Symposium, held in San Francisco, CA – June 29 – July 2, 2008.

Bai, M., Standifird, W., and McLennan, J.D.: “Modeling Fluid Mixture Transport and Cross-Flow in Layered Media,” ARMA 09-33 for presentation at Asheville 2009, the 43rd US Rock Mechanics Symposium and 4th U.S.-Canada Rock Mechanics Symposium, Asheville, NC: June 28th – July 1, 2009.

Bai, M., McLennan, J., and Standifird, W.: “An Alternative Method for Predicting Injectivity Decline in Produced Water Re-injection,” SPE 120829, for presentation at the 2009 SPE European Formation Damage Conference, Scheveningen, The Netherlands, 27-29 May 2009

McLennan, J.D Tran, D., Zhao, N., Thakur, S. Deo, M., Gil, I., and Damjanac, B.: “Modeling Fluid Invasion and Hydraulic Fracture Propagation in a Naturally Fractured Rock, a Three Dimensional Approach,” SPE 12788 2010 SPE International Symposium and Exhibition on Formation Damage Control, Lafayette, Louisiana, USA, 10-12 February 2010.

Research Interests

Energy extraction related to:

  • Exploration
  • Drilling
  • Completion
  • Stimulation
  • Production

John is a USTAR Associate Professor in the Department of Chemical Engineering at the University of Utah. He holds a Ph.D. in Civil Engineering from the University of Toronto, Canada (1980). His experience extends to petroleum service and technology companies. He worked for Dowell Schlumberger in Denver, Tulsa and Houston; later, with TerraTek in Salt Lake City, Advantek International in Houston, and ASRC Energy Services in Anchorage. He has worked on coalbed methane recovery, mechanical properties determinations, produced water and drill cuttings reinjection, as well as casing design issues related to compaction. John’s recent work has focused on optimized gas production from shales and unconsolidated formations.

Shale Gas Phase 2

The three key elements for a successful low permeability reservoir play are gas-inplace, heterogeneities providing permeability in excess of the matrix, and successful stimulation. EGI has been addressing the first of these directly, performing fundamental measurements to indicate the formation and reservoir parameters that govern recoverable gas-in-place. Storage mechanisms (adsorption, compressibility, and dissolution) were determined as functions of gas species, pressure history (reliable lost gas measurements), moisture content, and mineralogy. Without reliable gas-in-place forecasts, and the ability to identify desirable settings in advance, play development is expensive and prolonged.

Stimulating Low Permeability Reservoirs

In any low permeability formation – shale, tight sands, oil shale, geothermal, etc. – effective stimulation entails developing extensive, interconnected fracture systems with adequate conductivity. This effort leverages from projects awarded to the Department of Chemical Engineering by RPSEA for development of new generation simulators. This simulation methodology interrelates formation heterogeneity (stresses, fractures, high permeability streaks) with simulations of the growth of fracture systems during injection; and represents production from this specific, complex fracture network – next generation integrated geologic and production simulation.

Enhanced Geothermal Systems

EGI’s geothermal group is engaged in development work for Enhanced Geothermal Systems. Hydraulic injection (either above or below fracturing pressure) is one method to develop an enhanced fracture system, providing surface area for exposure of liquids to elevated temperature en route to producing wells and subsequent conversion to usable energy. The key element of these systems is that they are engineered. Fractures are created with optimal morphology by exploiting the in-situ stresses and natural heterogeneity – engineering fracture growth for heat extraction.