Annual Sheriff Lecture - University of Houston
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Annual Sheriff Lecture


  • The abstract title is limited to 300 characters, and the abstract text is limited to 2,000 characters, excluding spaces but including punctuation.
  • Poster dimensions are landscape orientation, 42” x 72”
All poster titles and abstracts should also be emailed to Kirene at, no later than 4:00p on Monday, October 22. Any submissions received after this deadline will not be accepted. Prizes will be awarded for the top judged posters in each of the following categories - 

Advanced PhD 
2nd year MS/1st year PhD 
Undergraduate/1st year MS

Speaker:  Dr. Gary Mavko,  Stanford University

Lecture:  Navigating Messy Rock Physics Problems

Two common tools for modeling physical properties of rocks are Estimators and Bounds.  Estimators predict a particular value of rock property:  for example, Archie’s Law to predict saturation or porosity, or Gassmann’s equations to predict how effective moduli change when the pore fluid changes.  In contrast, bounds predict the range of possible rock properties, given the limited information that we typically have in geophysics.  Rock microstructure and heterogeneity are critical – determining where the measured value falls within the bounds, and why predictors sometimes fail or mislead us. 

In this presentation, I’ll show strategies for using bounds to navigate messy rock physics problems.  Examples include (1) using bounds to test and sometimes falsifying popular predictors, (2) using bounds to infer microstructure from common measurements, and (3) using bounds, themselves, as predictors, especially in complex materials such as unconventionals.  I’ll also touch on a less familiar topic:  using bounds on the cross-relations between different measurements (elastic modulus, electrical resistivity, dielectric constant, thermal conductivity, etc.) on the same rock.  Cross bounds help us to validate our multi-physics measurements and our assumptions used to interpret measurements.


Norris Conference Center, CityCentre              
816 Town and Country Blvd                           
HoustonTX  77024
United States

Date & Time: 

12 Novemeber, 2018
5:30-6:30 Posters and social hour
6:30-7:30 Dinner
7:30-9 pm Presentation

Please visit the HGS website to register for this event.



Gary Mavko is a Professor of geophysics at Stanford University. He received his Ph.D. in geophysics from Stanford in 1977. Gary then joined the Tectonophysics branch of the USGS in Menlo Park where he worked in areas of rock physics and earthquake fault mechanics. In 1984 Gary joined Entropic Geophysical, where he developed many of Entropic’s algorithms and software for reflection and refraction analysis, and eventually became their VP of research and development. He returned to Stanford in February, 1989, and is now Professor (Research) of Geophysics. He has been working on modeling and analysis of the acoustic properties of rocks and techniques of seismic interpretation for rock and fluid properties. In 2001 he was elected an Honorary Member of the Society of Exploration Geophysicists "for his deep understanding of rock physics and for the distillation of his ideas into the “squirt” theory for porous, saturated rocks". Gary was a 2006 Distinguished Lecturer of the Society of Exploration Geophysicists.