Articles

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June 2015

Full-Waveform Inversion: Challenges, Opportunities and Impact

Dimitri Bevc

There has been a great deal of industry activity and interest in full-waveform inversion (FWI) because of its potential to generate accurate high-resolution velocity models. Theoretically, the method has great promise, and compute power seems to be adequate to bring this promise to bear on practical business problems. The promise…

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June 2015

Introduction to June Focus: Unconventional Resources

Marco Perez

Within the unconventional era of hydrocarbon exploitation, a geophysicist is asked the “question” of how to high-grade drilling locations for optimal and efficient reservoir development. He, or she, is asked to interpret subtle changes in elastic property estimated from surface measurements, on rock thousands of meters beneath the earth’s surface.…

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June 2015

Interpreting AVOAz using limaçons

Benjamin Roure

Limaçon is a French word meaning snail (from the Latin word limax). In the real world, limaçons have a wide range of applications from culinary (a delicacy in some countries) to cosmetics (their slime is used for human skincare). In the mathematical world, limaçons (also known as Pascal’s limaçons after…

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June 2015

Short note: Estimation of anisotropic minimum horizontal closure stress

Bill Goodway

In the past seismic imaging and AVO were driven by isotropic models of the Earth. More recently the use of quantitative interpretation attributes to characterize unconventional reservoirs has continued within this isotropic assumption. However, at the 2013 SEG convention, Leon Thomsen argued that industry has been doing AVO wrong for…

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June 2015

Shear wave anisotropy estimates via azimuthal amplitude-variation-with-offset inversion

David Cho, David Miller, Mark Norton, Ayon Kumar Dey and Frederick Kierulf

Traveltime and amplitude based techniques to detect seismic anisotropy have inherent differences in their assumptions and the underlying physics used to describe the seismic response. For this reason, they often produce conflicting solutions, which can lead to inconsistencies between the results. Traveltime methods estimate an interval property, providing an easy…

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June 2015

Airborne Electromagnetic Systems – State of the Art and Future Directions

Jean M. Legault

Airborne electromagnetics (AEM) is easily one of the most popular geophysical methods used in mineral exploration around the world and is possibly second to only aeromagnetics-radiometrics as being the most widely deployed. AEM was initially developed after the Second World War to explore for mineral deposits (Fountain, 1998), and since…

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May 2015

From Recommender Systems to 5D Seismic Data Reconstruction

Mauricio D. Sacchi

In recent years, the development of recommendation systems has become an important area of research for data scientists. A recommendation system (or recommender system) is an algorithm that attempts to predict the rating that a user or costumer will give to an item. Recommendation systems have become quite popular in…

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May 2015

Introduction to May Focus: Rock Physics

Douglas R. Schmitt

Practitioners of Rock Physics can sometimes become quite Emo when a bunch of Punks call us Geeks because we Breakcore and Grindcore. But, if you need to make a piece of Experimental Rock, particularly if it is from a Hard-core, you sometimes have to Thrash it in your Garage. Okay,…

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May 2015

Resistivity and density estimation from multicomponent seismic data: case study from the lower cretaceous McMurray formation, Athabasca Oil Sands

Fred Mayer, Carmen C. Dumitrescu, Glenn Larson

We present a case study of oil sands reservoir characterization using resistivity and density seismic volumes estimated from multicomponent seismic data. In the Athabasca Oil Sands region of Alberta, the Lower Cretaceous McMurray Formation is the reservoir. In this reservoir the sand can be differentiated from shale based on density.…

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May 2015

Empirical relations between ultrasonic P-wave velocity, porosity and uniaxial compressive strength

Xiwei Chen, Douglas R. Schmitt, James A. Kessler, James Evans, Randy Kofman

The uniaxial compressive strength (UCS) is one of the most important geotechnical properties of rock and it has been widely used in geological and geo-mechanical engineering projects. In this study, UCS and other basic physical properties of 165 basalt samples at 55 different depths along zone of interest (ZOI) from…

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May 2015

Study of elastic anisotropy on an unconventional ‘shale’ rock using ultrasonic waves and static strain measurements

O.N. Ong, J. Meléndez-Martínez, D.R. Schmitt, and R. Kofman

Elastic anisotropy is a seismic attribute defined as the variation of wave speed as a function of its propagation direction within a medium. With the increase in interest of unconventional reservoirs, the incorporation of anisotropic factors is a necessity to provide more accurate seismological models. Without consideration of anisotropic effects,…

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May 2015

Survey Responses on the Public Perception of Induced Seismicity

Neda Boroumand

A survey was issued by the Canadian Society of Exploration Geophysicists (CSEG) to gauge the public’s perception of induced seismicity (IS) in the summer of 2014. It revealed that education efforts on IS should be collaborative involving industry, academia and regulators, but documents issuing from this work must crucially be…

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May 2015

2014 CSEG Awards

2014 CSEG Award Winners.

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April 2015

Introduction To April Focus: Land Seismic

Rob Vestrum

The papers in this section on Land Seismic were inspired by the Land Seismic Workshop in Banff, September 23 to 25, 2014. The workshop was jointly held by the CSEG and the EAGE, and the technical sessions included as much discussion time as presentation time. Our vision was to collect…

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April 2015

On the use of coincident shots and receivers in Megabin geometry and in orthogonal geometry

Gijs J. O. Vermeer

Recently two papers were published in the RECORDER that dealt with a comparison of Megabin geometry with orthogonal geometry in the context of 5D interpolation (Duncan et al., 2014; Harger and Schweigert, 2014). What struck me is the use of coincident shots and receivers in the Megabin geometries and also…

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April 2015

The advantages of applying cableless technology: A case study in Colombia

Hector A. Alfonso

The results and experiences from a 3D survey recently carried out by Ecopetrol and its partner Talisman, in the Llanos Basin of Colombia, are presented. More than 8000 channels patch on land were used for the first time in Colombia using cableless technology.

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April 2015

Seismic exploration in extreme topography: Acquisition for optimal imaging

Mike Hall, Peter Maxwell, and Anna Leslie

Seismic exploration in areas of rugged and extreme topography is dangerous, difficult and expensive. Because of these environmental and economic factors it is not uncommon for data acquired in such areas to be inadequately sampled in space for imaging purposes. Also, long source-receiver offsets are often required in order to…

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April 2015

An integrated strategy: constrained tomography inversion of multi-type data for near surface velocity model building

Liansheng Liu, Lidong Gao and Zhiyu Zhang

After analyzing the theory assumptions and the pros and cons of three methods in near surface model building, which have been widely used in data processing, the three of us all agree that an “Integrated Strategy”, based on constrained first arrival tomography inversion, should be introduced as described in this…

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April 2015

CRS azimuth gathers and CRS shot gathers for improved fault imaging in Alpine 3D seismic data

Henning Trappe, Eliakim Schuenemann, Juergen Pruessmann, Sonja Suckro, Hans-Gert Linzer, Martin Schachinger

In a case study from the Austrian Alps, the capability of Common-Reflection-Surface processing (CRS) for comprehensive fault imaging and analysis is demonstrated. CRS processing is used to generally improve the signal-to-noise ratio and to regularize the dataset in different domains. We show an offset-azimuth regularization to generate well populated gathers…

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April 2015

Introduction to April Technical Articles

Amanda Knowles

Because we had a surplus of fantastic papers for last month’s Value of Integrated Geophysics (VIG) Edition, the April RECORDER carries a continuation of similarly themed articles.

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