Articles
Azimuthal Fourier Coefficients
Jon Downton, Benjamin Roure and Lee Hunt
Azimuthal AVO analysis can be split into two parts: the Amplitude Versus Offset (AVO) analysis and the Amplitude Versus Azimuth (AVAz) analysis. For regularly sampled data in azimuth, the properties of the Fourier transform allow these problems to be treated separately. If we calculate a Fourier transform of the AVAz…
Practical Seismic Petrophysics: The Effective Use of Log Data for Seismic Analysis
Tad Smith
This study demonstrates empirical relationships derived from microseismic, 3D inversion attributes and 4D seismic to production in unconventional shale in the Horn River Basin. Production variations are explained through the use of the above mentioned tools and a careful investigation of stimulated rock volume. These production variations are shown to…
Investigating anisotropy in rocks by using pulse transmission method
Jaime Meléndez Martínez and Douglas R. Schmitt
Recent interest in unconventional reservoirs motivates our work in laboratory measurements of seismic anisotropy. Seismic anisotropy is the variation in speed of a wave as a function of its direction of propagation. Analyzing anisotropy in unconventional reservoirs is important since anisotropy leads, for example, to differential stresses upon loading and…
Integration of Rate-Transient and Microseismic Analysis for Unconventional Gas Reservoirs: Where Reservoir Engineering Meets Geophysics
Christopher R. Clarkson
Unconventional gas reservoirs, including tight gas, coalbed methane and shale gas reservoirs, have become a significant source of natural gas supply in North America, and are becoming actively explored for, and in some cases exploited, globally. Most recently, liquids-rich (wet gas, gas condensate and light oil) plays have become a…
Guns, Vibes and Channels
R. Malcolm Lansley
This talk will discuss the nature of recent changes in the seismic industry and the benefits that have resulted. Improvements have been made in recording technology and equipment and these have enabled newer and greatly improved methods of recording data. The increased power of computing systems has allowed efficient data…
Hydraulic Fracture Height Growth
Shawn C. Maxwell
Hydraulic fracture stimulations or ‘fracs’ are vital for economic production in low permeability tight gas and shale gas reservoirs, and the frac height is a key factor for engineers to optimize the hydraulic fracture treatment. As unconventional reservoir development has spread through North America and specifically to regions unaccustomed to…
Hydraulic fracturing: Coulomb failure stress in fracture networks
Kris Vasudevan and David W. Eaton
In hydrocarbon-producing sedimentary basins, the crust can be modelled as a poroelastic medium. The stress state of a poroelastic medium, which entails both the shear and normal stress of the rock, is influenced by pore-fluid diffusion. Coulomb stress changes due to pore pressure changes in a poroelastic medium may lead…
An Introduction to Practical Modeling of Reservoir Geomechanics for Appraisal and Development
Vikram Sen and A. (Tony) Settari
The inter-linking or coupling of geosciences with engineering in cross-disciplinary studies has become increasingly popular in recent years. In the context of the Canadian oil and gas industry, this particularly applies to two major areas: (i) hydraulic fracturing based stimulation of unconventional (i.e. tight) reservoirs or shales, and (ii) thermal…
SEG Distinguished Lecture: Imaging the Earth’s near surface: The why and how of applied geophysics for the 21st century
Douglas W. Oldenburg
The top few kilometers of the Earth’s surface are of extreme importance to our society. This near-surface region houses mineral and hydrocarbon wealth that are crucial for industrialized development, water needed for life, and it is an environment with which we must interact to build our infrastructure. To exploit these…
Fault-Plane Solutions from Moment Tensor Inversion for Microseismic Events using Single-Well and Multi-Well Data
Jing Du, Ulrich Zimmer, and Norm Warpinski
Although microseismic monitoring of hydraulic fractures has primarily been concerned with the dimensions, complexity, and growth of the fractures or fracture systems, there is an ever-increasing desire to extract more information about hydraulic fracturing and/or natural fractures from microseismic data. Source-mechanism analysis, which is concerned with deducing details of the…
What Does Microseismic Tell Us About Hydraulic Fracture Deformation
Shawn C. Maxwell
With the expansion of microseismic imaging of hydraulic fracture stimulations in the past few years, interest has evolved from simply the event locations to extracting more information from the signals through advanced source characterization. Details about the fracturing and deformation associated with the microseismic source can be investigated using earthquake…
Noise Examples from Two Microseismic Datasets
Andy St-Onge and David W. Eaton
The recording of microseismic surveys can be used to monitor hydraulic fracture stimulation of reservoirs. In these surveys, the continuous recording of three component geophones are used to detect P and S wave energy induced by the fracturing process and related stress changes. This paper presents a number of noise…
Advanced seismic techniques help in characterizing a challenging Jean Marie carbonate play, NE British Columbia, Canada – a Case Study
Dragana Todorovic-Marinic, Satinder Chopra and Mark Edmonds
This paper describes a workflow that was adopted for understanding the porosity and permeability distribution in the Jean Marie carbonate play in British Columbia, Canada. It makes use of some advanced seismic techniques and holds promise of being a robust methodology that has resulted in enhanced deliverability and recovery of…
The Use of 3-component Seismic Data to Identify Sweet Spots in Fractured Bakken Reservoirs
Scott Stockton
In October 2008, Vector acquired and processed an experimental 2D seismic line in Mountrail and Ward Counties ND. In recent years, several operators have been successful drilling long-lateral horizontal wells in the Middle Bakken using surface seismic only loosely for approximate structural control. The efficacy of conventional surface seismic data…
Improvements in microseismic data processing using sparsity and non-linear inversion constraints
Ismael Vera Rodriguez, Dave Bonar and Mauricio Sacchi
This study explores improvements obtained in microseismic data processing through the application of inversion techniques that utilize sparse and non-linear constraints. Specifically, we present a method for de-noising microseismic traces and a method for the automatic time picking of microseismic events. The de-noising method is based on a sparsity constrained…
Synthetic Microseismic Datasets
Joe Wong, Peter M. Manning, Lejia Han, and John C. Bancroft
Microseismic or passive seismic monitoring during hydraulic fracturing processes involves recording 3C seismograms produced by microearthquakes associated with breaking rock. By analyzing the data to locate hypocenters where the breakage occurs, geophysicists enable reservoir engineers to follow the growth and evolution of the fractured rock volume in time and space.…
Fast Search Algorithms for Automatic Localization of Microseismic Events
Ulrich Zimmer and Jeremy Jin
Automatic localization of microseismic events has become an important tool in characterizing formations which generate large numbers of microseisms during hydraulic fracturing, e.g. Horn River shales. Especially for large complex threedimensional velocity models, the automatic processing requires the use of specialized optimization algorithms to locate the events within an acceptable…
Anisotropic PSTM Imaging for Unconventional Reservoirs
Edward Jenner
Exploration and drilling efforts in onshore North America have increasingly moved away from conventional reservoirs and toward unconventional ones. Although advances in drilling technology have been the primary factors in achieving economic viability in these tight reservoirs, 3D seismic data has played an increasingly important role in development success.
... Compressive sensing in seismic exploration: an outlook on a new paradigm
Felix J. Herrmann, Haneet Wason, and Tim T.Y. Lin
Many seismic exploration techniques rely on the collection of massive data volumes that are subsequently mined for information during processing. While this approach has been extremely successful in the past, current efforts toward higher resolution images in increasingly complicated regions of the Earth continue to reveal fundamental shortcomings in our…
The Evolving Role of Geophysics in Exploration. From Amplitudes to Geomechanics
Eric Andersen and David Gray
Over the last 25 years, geophysical analysis of seismic data has greatly evolved. However, in the routine utilization and daily workflows of many exploration and development teams, geophysical technology is at a standstill. This paper came though our observations and dealings with many geophysicists over time. We’ve been involved with…
