2763 search results for:
Wavelet estimation by non-linear optimization of all-pass operators
Somanath Misra and Mauricio Sacchi
…Abstract A mixed phase wavelet can be parameterized as a convolution of a minimum phase wavelet and an all-pass wavelet. The minimum phase wavelet can be estimated from the data by the Wiener-Levinson algorithm. The technique of cumulant matching is used to estimate the phase of the all-pass wavelet. Higher…
Developments in seismic anisotropy: Treating realistic subsurface models in imaging and fracture detection
Ilya Tsvankin and Vladimir Grechka
…Introduction The scope of recent advances in the field of seismic anisotropy is too wide to be thoroughly analyzed in a short overview article. Here, our goal is to emphasize several key recent developments and trends and give a limited number of essential references. After several decades of mostly theoretical…
Towards wave-equation imaging and velocity estimation
Samuel Gray, Daniel Trad, Biondo Biondi, Larry Lines
…Introduction Prestack depth migration (PSDM) has gained widespread acceptance as a tool of choice for seismic imaging in geologically complex areas. Its ability to honor lateral velocity variations gives geophysicists greater confidence in the precise location of their drilling targets on their image than they can possibly have using prestack…
Regularized migration/inversion: New Generation of Seismic Imaging Algorithms
Mauricio Sacchi, Juefu Wang, and Henning Kuehl
…Abstract Linearized seismic inversion demands minimizing a cost function of the form where L denotes the forward modeling operator that maps an angle dependent reflection strength m to a measurable seismic wave field d. Minimizing the cost function J in a least-squares sense, leads to the so-called least-squares migration methods.…
Significant developments in multicomponent seismic exploration in the last five years and future directions: Recent developments in converted PS-wave analysis processing of shear S-wave splitting and prestack migration
James Gaiser and Tony Probert
…There have been tremendous advancements in 3D multicomponent seismic acquisition, processing, analysis and interpretation over the past five years. Improvements have been made in PS-wave (converted-wave) signal processing, including velocity analyses and anisotropy, interpretation and event registration of PP and PS data, and prestack imaging. Both PS-waves and P-waves (compressional…
Advances in Land Multicomponent Seismic: Acquisition, Processing and Interpretation
Coordinated by Robert Kendall
…Introduction Land multicomponent seismic has garnered significant attention and demonstrated substantial growth in the last five years. The bulk of this growth in multicomponent activity has been in western Canada. While multicomponent seismic has been around for many years, historical cost and quality concerns have limited its use as a…
Delineating a sand channel using 3C-3D seismic data: Ross Lake heavy oilfield, Saskatchewan
Chuandong (Richard) Xu and Robert Stewart
…Introduction The Ross Lake oilfield, operated by Husky Energy Inc., is located in south-western Saskatchewan, Canada. The reservoir is at about 1150m depth and is interpreted as a lower- Cretaceous, incised-valley channel sand in the Dimmock Creek member of the Cantuar formation of the Mannville Group. The sand has high…
Practical applications of P-wave AVO for unconventional gas Resource Plays – I: Seismic petrophysics
Bill Goodway, John Varsek and Christian Abaco
…Introduction For the past few years natural gas exploration in North America has focused on the huge resource potential of unconventional reservoirs such as coalbed methane (CBM), tight gas sands and shales. These gas accumulations, termed Resource Plays at EnCana, are low permeability-porosity reservoirs, with gas stored in natural fractures…
An Inversion Primer
Brian Russell, Dan Hampson, Bradley Bankhead
…Introduction Seismic inversion is a technique that has been in use by geophysicists for almost forty years. Early inversion techniques transformed the seismic data into P-impedance (the product of density and P-wave velocity), from which we were able to make predictions about lithology and porosity. However, these predictions were somewhat…
The New Reservoir Characterization
John Pendrel
…Introduction – The Early Years 1970-1995 When the author arrived at Gulf Science and Technology Company in Pittsburgh, PA, in 1977, post-stack seismic inversion to acoustic impedance had been in common use there for about two years. The algorithm was a simple one – every seismic sample was assumed to…
Seismic Attributes – a promising aid for geologic prediction
Satinder Chopra and Kurt Marfurt
…Seismic attributes have come a long way since their introduction in the early 1970s and have become an integral part of seismic interpretation projects. Today, they are being used widely for lithological and petrophysical prediction of reservoirs and various methodologies have been developed for their application to broader hydrocarbon exploration…
Recent Advances in Rock Physics and Fluid Substitution
Tapan Mukerji and Gary Mavko
…Understanding the Rock Physics Links Between Geologic Processes and Seismic Signatures One of the most important developments in rock physics has been progress toward quantifying the relations between geologic processes and geophysical signatures. Historically, the majority of rock physics research was done by physicists. Their theoretical models – some very…
Future challenges and unexplored methods for 4D seismic analysis
Martin Landrø
…Summary The two major challenges that 4D seismic analysis will face in the next decade is to make it work for carbonate reservoirs and to extract production related information from 4D data sets where the signal to noise ratio is low. In order to meet these challenges we have to…
A personal perspective on the past, present and future of Time Lapse seismic monitoring
Keith Hirsche
…As I write this article, I am sitting on another airplane crossing the Atlantic, and I wonder why I promised Satinder that I would write an article about Time Lapse seismic monitoring for the RECORDER. On the other hand, it would have been very difficult to refuse since there are…
Rock Physics Strategies for Facies and Fluids Mapping
Gary Mavko
…Abstract Over the last decades enormous strides have been made to understand the relations between the physical properties of reservoir rocks and their geophysical signatures — the science now known as Rock Physics. We have gradually discovered more and more order in relations that once appeared disappointingly scattered, for example,…
Talisman Energy Inc. in New York State
Timo Von Rudloff
…Introduction In 2000 Talisman Energy Inc. began a project to drill and produce gas in the northern Appalachian Basin of the United States. In particular, it evaluated and entered into operations in the states of New York and Pennsylvania, with ongoing consideration given to the neighbouring states, like Ohio and…
My Life in the Trenches
Doug Pruden
…In 1999, while oil prices were crashing, the company for which I worked encountered some financial difficulties and was forced to sell (at a significantly discounted share price!). Being 41 years old and forced to make an unplanned career move, I found myself pondering the eternal midlife question, “What do…
Glimmer of Sunshine in the Field
Mike Doyle
…Maybe there is a glimmer of sunshine in the business of seismic this year. This year marks the first in many where programs simply did not get shot. It marked a slight realization by seismic contractors that they may be able to do something on some of their risk clauses.…
Too many seismic attributes?
Arthur Barnes
…Are there too many seismic attributes? Their great number and variety is almost overwhelming. How can one decide which ones to use? But it is not as bad as it looks. Throw away all the unnecessary attributes and what is left over is quite manageable. It’s easy to identify unnecessary…
Outreach Committee Launches Ambassadors Program
Doug Uffen
…Formed three (3) years ago, the CSEG Outreach Committee is charged with promoting the science of geophysics on behalf of the society. The role of the Outreach Committee is essentially one of communication. While the CSEG officially stands for the Canadian Society of Exploration Geophysicists, the society has functioned essentially…
