Patents by Inventor Amy D. F. Day-Lewis

Amy D. F. Day-Lewis has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Predicting changes in hydrofrac orientation in depleting oil and gas reservoirs
    Patent number: 7848895
    Abstract: Stress rotation due to depletion can be estimated in reservoirs having an impermeable reservoir boundary. More specifically, the isotropic change in stress due to depletion, and the uniaxial stress resulting from a change in pore pressure across an impermeable boundary are both modeled as perturbations to an initial stress state. These perturbations can result in a rotation of the principal stress directions. Estimates of the stress rotation are helpful for hydraulic fracturing operations, because fracture tends to occur in a plane perpendicular to the least principal stress.
    Type: Grant
    Filed: January 15, 2008
    Date of Patent: December 7, 2010
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Mark D. Zoback, Amy D. F. Day-Lewis, Sangmin Kim
  • Predicting changes in hydrofrac orientation in depleting oil and gas reservoirs
    Publication number: 20080249721
    Abstract: Stress rotation due to depletion can be estimated in reservoirs having an impermeable reservoir boundary. More specifically, the isotropic change in stress due to depletion, and the uniaxial stress resulting from a change in pore pressure across an impermeable boundary are both modeled as perturbations to an initial stress state. These perturbations can result in a rotation of the principal stress directions. Estimates of the stress rotation are helpful for hydraulic fracturing operations, because fracture tends to occur in a plane perpendicular to the least principal stress.
    Type: Application
    Filed: January 15, 2008
    Publication date: October 9, 2008
    Inventors: Mark D. Zoback, Amy D.F. Day-Lewis, Sangmin Kim