Articles
The New Role of Petrophysics in Geophysical Interpretation
E.R. Crain
The role of petrophysics in seismic interpretation has taken a major leap forward in the past ten years, resulting from important advances in seismic data processing techniques, particularly seismic inversion, attribute analysis, and amplitude versus offset methods that showed we could estimate reservoir properties from such data. Coupled with the…
VSP Reflection Points for Linear Inhomogeneity and Elliptical Anisotropy
C.J. Wheaton and M.A. Slawinski
An exact analytical expression for traveltime in a medium with a constant velocity gradient and elliptical velocity dependence is used to calculate possible reflection points for a given source receiver geometry. The set of reflection points are collectively referred to as the illumination zone. Also, we give an expression that…
DoodleTrain on Track
Bill Nickerson
... Smearing the sideslip and other anisotropy problems, or — “Don’t hate me because I am beautiful: 3D anisotropic depth migration in the Canadian Foothills”
Robert Vestrum
Seismic waves exhibit fascinating, non-intuitive behaviours in the presence of anisotropy. Seismic anisotropy refers to the characteristic of materials, such as shale-dominated clastics, where the seismic velocity changes with direction of wave propagation. We explore wave-propagation phenomena and their effects on seismic imaging of complex-structure exploration targets below anisotropic strata.
... Where you sit governs what you see
Heloise Lynn
If you sit at a seashore, you see sand and waves and ocean and sky …..or, do you see sand and dune and cliff and rocks and trees and sky? Well, obviously, which way you face governs what you see (unless you have eyes in the back of your head).…
Permeability Anisotropy from Seismic Anisotropy and Other Holy Grails
Heloise Lynn
Permeability anisotropy from seismic anisotropy is an exciting avenue to gain insights into the aligned flow conduits – the aligned connected porosity – which set up a form of seismic anisotropy.The last SEG Annual Meeting (2002) had an entire session on the relationships between seismic anisotropy and permeability anisotropy. [Do…
High-dimensionality 3D seismic data visualization and interpretation: Simultaneous interpretation of nine co-rendered volumes
Heloise Lynn, Ping Chen, and Chenyi Hu
Many 3D volumes of attributes derived from travel times or amplitude measurements are useful for geologic insights when wide-azimuth, or multicomponent surveys are processed for the attribute value itself and the azimuthal characteristics of the value. For wide-azimuth 3D PP data, Vrms PP, Vint PP, AVO, and their elliptical variations…
Interpreting seismic data in the presence of azimuthal anisotropy; or azimuthal anisotropy in the presence of the seismic interpretation
Marty Williams and Edward Jenner
Measuring P-wave azimuthal anisotropy has been in the recent past an elusive task; therefore, the interpreter ignored this attribute of the seismic data and left the subject to the research and technology group geophysicists. Conversely, the interpreting geophysicist knew that when measured, the anisotropy could yield important reservoir properties related…
Fractured Reservoir Characterization using AVAZ on the Pinedale Anticline, Wyoming
David Gray, Sean Boerner, Dragana Todorovic-Marinic and Ye Zheng
The Pinedale Anticline in Wyoming, USA, has become an area of particular interest since the recent success of several wells that have produced significant volumes of gas from its tight sandstone reservoirs. Production from these reservoirs is now possible using new stimulation techniques developed in the neighboring Jonah Field. The…
Mars in Canada: The NASA Haughton-Mars Project, Devon Island, Nunavut
Robert R. Stewart
The Haughton meteorite impact structure on Devon Island, Nunavut is a fascinating geologic site as well as one of the most Mars-like places on Earth. Similar, but not quite as harsh as Mars, the Haughton crater is cold (average temperature –17°C), dry, rocky, dusty, and windy. Dr. Pascal Lee, of…
Fractured Reservoir Characterization using AVAZ on the Pinedale Anticline, Wyoming
Dave Russum
Resource assessments have generally attempted to estimate the total resource in an area or formation. This approach can provide very large numbers that are misleading for both industry experts and the general public. This paper proposes a new, simple method to assess resources that recognizes that not all resources are…
A Perspective on the Evolution of Processing Seismic Primaries and Multiples for a Complex Multidime
Arthur Weglein
Seismic reflection events are typically catalogued as primary or multiple depending on whether the arriving energy at the receiver has in its history experienced one or more upward reflections, respectively. We can trace the evolution of progress and effectiveness in seismic processing by following the physics used to describe what…
A Tomostatics Primer
Mike Perz
First arrival turning ray tomography is enjoying increasing popularity as a tool for deriving both weathering statics and near-surface velocity models for depth imaging. This tutorial-style article focuses on the former of these two applications, the so-called “tomostatics” algorithm.
... Playing with Fire: Trim Statics and Noise Alignment
Chuck Ursenbach and John C. Bancroft
The danger of noise alignment in trim statics is reviewed and illustrated. Such noise alignment is then quantified through numerical studies to obtain a clearer understanding of this phenomenon. The results are used to quantify an allowable range of trim statics for a given acquisition geometry, and to develop tests…
“Is There an Impending World Oil Shortage?”
Michael J. Economides
In 1859, right after the now famous Colonel Drake well was drilled in Titusville, Pennsylvania, and because of shortages of the illuminant camphene, shortages caused by the Civil War, the price of oil shot to $15 per barrel which in today’s dollars would be over $1,000. By autumn of 1861,…
APEGGA/CSEG Synergies
Ron Tenove
Ron Tenove heads the largest professional association in Alberta. He has a clear understanding of the realities of today and a strong vision of where the professions are heading and how to get there. With total membership now exceeding 38,000, APEGGA faces many challenges from our changing professions and new… A Quick Tour of University Geophysics Websites
Brief overview of Canadian university websites on the subject of geophysics.
... Geophysics Research at the University of Calgary
Helen Isaac and Larry Lines
The Department of Geology and Geophysics at the University of Calgary began its geophysical life in 1967, when Dr. Peter Gretener joined the department. A geophysics major was first offered in 1970 and the first Ph.D was awarded to Art Sweet in 1972. The department now has high enrolments at…
Research in Geophysics at the University of Alberta
Douglas R. Schmitt
The wide variety of research in Geophysics at the University of Alberta includes both applied and more fundamental studies. The core faculty of solid earth Geophysicists are in the Physics Department but workers are also scattered throughout other departments and faculties. There have been many changes at the University of…
Geophysics Research at Colorado School of Mines
Terry Young
When some people first hear of the Colorado School of Mines, they are not sure whether it is “Mines” or “Minds”. For many, the reference to “Mines” conjures up a limited image of what this institution must be about. It may be a surprise, then, to learn that “Mines”, aboard…
