Articles
Real vs. ‘5D’ Data: An analysis of acquired vs. interpolated data in both the post-stack and the pre-stack domains for parallel and orthogonal geometries
Emily Duncan, Ann O’Byrne and Jillian Dalsin
5D Interpolation was introduced in 2005 as an infill technique that ‘although not a substitute for well-sampled field data, … provides some useful data preconditioning that in particular allows migration techniques to work better’ (Trad et al., 2005). This multidimensional algorithm was pushed by the industry to overcome acquisition constraints…
No magic from 5D interpolation on a coarse 3D oilsands dataset – a case history
Sylvestre Charles, Jim Hostetler, Jiwu Lin, Xiaoming Luo, Kevin Roberts
This case history is based on a coarse 3D seismic dataset that was acquired for a commercial Steam Assisted Gravity Drainage (SAGD) project in the Athabasca oil sands in Alberta. In conjunction with a dense core-hole drilling program, this legacy 3D seismic dataset was acquired to better understand the geological…
Can interpolation improve QI?
Laurie M. Weston Bellman
It seems too good to be true – creating seismic data in processing at a fraction of the cost of actually recording it. Nevertheless, the practice of seismic interpolation has been an increasingly popular trend in recent years with the latest 5D algorithms becoming an integral piece of the pre-stack…
A Journey Through Time In Search of Arabian Giants – Oil/Gas Fields, Recording Channels, and Petabytes
Peter I. Pecholcs
This journey began 22 years ago when I first arrived in Dhahran, Saudi Arabia, the land of giant oil and gas fields. It was at a time when the search began for new giants outside the Eastern Province (Retained Area 1), which is home to the world’s largest oil field…
Introduction to February Focus: Anisotropy: Fractures and Faults
Rob Kendall
Welcome to this special issue of the RECORDER that presents five papers on fractures and anisotropy. While this theme has been in and out of the spotlight for many years, we are seeing novel approaches for extracting even more information from the data than we were a mere five years…
On Hookean solids in seismology: anisotropy and fractures
Michael A. Slawinski
Geophysics—similarly to astrophysics—relies on remote sensing. Inferring material properties of the Earth’s interior is akin to inferring the composition of a distant star. In both cases, scientists rely on matching theoretical predictions or explanations with observations. Notably, obtaining a sample of a material from the interior of our planet might…
Results from diverse fracture analysis methodologies: consistent, contradictory, or complementary?
M. Perz, P. Cary, X. Li, S. Chopra, and L. Hunt
We examine four independent approaches to fracture detection using surface-seismic data. Fundamental algorithmic properties and limitations are studied in an attempt to explain observed differences between the attributes generated from the various approaches. Real data examples are presented, including one which demonstrates simultaneous analysis of all four techniques and which…
Case study: 3C and 9C prestack shear wave splitting analysis at Big Sky
Jeff P. Grossman and Gulia Popov
We present a tutorial style case study in which we compare two approaches to shear wave splitting (SWS) analysis and layer stripping on a subset of 3-D 9-C data from Montana. The first, and perhaps more familiar method, utilizes converted wave, or PS data, while the second utilizes pure shear…
Anisotropic moment tensor inversion and visualization applied to a dual well monitoring survey
S. Leaney, X. Yu, C. Chapman, L. Bennett, S. Maxwell, J. Rutledge and J. Duhault
In this paper we review the workflow used for anisotropic moment tensor inversion and visualization applied to a dual well monitoring survey from the West Pembina field in Alberta. The workflow makes use of an exact, dynamic, layered VTI ray-tracer that allows for constant dip. Included are a description of…
Evaluating fracture-induced anisotropy using borehole microseismic data
J-M Kendall, J.P. Verdon and A.F. Baird
For decades passive seismic monitoring has been a routinely used tool in earthquake engineering, mining and geothermal industries. In the past 10 years its use in the petroleum industry has seen an order of magnitude growth: in terms of annual revenue the global market is now more than a ¼…
Distributed Acoustic Sensing as a Fracture Diagnostic Tool
Paul Webster
Distributed Acoustic Sensing (DAS) is an acoustic detection technology that has recently been applied in production and geophysical settings. A single mode silica optic fiber in a cable is attached to a well bore and interrogated with laser pulses. An Interrogator Unit on the surface generates the laser pulses which…
Introduction to January Focus: Unconventional Reservoirs
Marco Perez
The promise of unconventional reservoirs is sustainable hydrocarbon production from previously inaccessible reservoirs. The high capital expenditure required to develop this resource and the depressed commodity prices makes for narrow profit margins and increases the focus on efficient and optimal project execution. Most of the focus is on lowering costs…
Hydraulic fracturing as a global cascade in networked systems
David Cho
Networked systems require the consideration of interactions between component parts as well as the parts themselves in understanding the properties of the system. In the case of hydraulic fracturing, the process can be regarded as the spread of a fractured state through an initially unfractured network of rock elements. In…
Unconventional shale gas reservoir characterization using the hitcube approach – The mapping of marl rich mudflows in the Horn River Basin
Claire Pierard, Hardeep Jaglan, Kristoffer Rimaila, Arnaud Huck, Friso Brouwer, Steve Jensen, Eric von Lunen
In unconventional reservoirs, the occurrence of marls is a significant risk to production and a major challenge to be able to locate and quantify them. As the marl thickness is often below the seismic resolution, an advanced characterization technique is needed. The HitCube inversion is an efficient stochastic inversion to…
The impact of interbed multiples on the inversion and interpretation of pre-stack data
Andrew Iverson
Unconventional resource plays commonly use a geophysical workflow involving analysis beyond stacked images and structural interpretation. This involves pre-stack quantitative interpretation methods such as inversion to obtain P-impedance and S-impedance (Zp and Zs) volumes that are then interpreted using rock physics and geomechanical templates (Close et al. 2012). The goal…
Breaking Structure: Why Randomized Sampling Matters
Felix J. Herrmann
During this talk, Felix Herrmann will explain how ideas from compressive sensing and big data can be used to reduce costs of seismic data acquisition and wave-equation based inversion. The key idea is to explore structure within the data by deliberately breaking this structure with randomized sampling, e.g., by randomizing…
Introduction to December’s Focus: Seismic Processing
Richard Bale
It is sometimes easy to forget, amidst the panoply of recent trends now enlivening geophysics – fractures, microseismic, reservoir monitoring, etc. – that much of our work relies on one main idea: extracting signal from data. In this issue, we revisit this basic principle and explore the implications in different…
Sparsity and band-limitation: Two sides of the same coin?
Mostafa Naghizadeh and Mauricio D. Sacchi
We introduce a strategy to identify the optimal sampling functions for Fourier reconstruction (5D interpolation) methods. We integrate the concepts of band-limitation and sparsity into a single decision criterion to select the sampling functions with the least amount of spectral interference in the Fourier domain. The analysis was carried out…
All roads lead to Rome: predictability, sparsity, rank and pre-stack seismic data reconstruction
Aaron Stanton and Mauricio D. Sacchi
In recent years researchers at universities, processing and oil companies have proposed several pre-stack seismic data reconstruction algorithms. In essence, all these algorithms are developed under a common assumption: there is sufficient simplicity in the observed seismic wavefield to permit its representation in terms of a finite number of basis…
A new, simple approach to surface-consistent scaling
Peter Cary and Nirupama Nagarajappa
Surface-consistent scaling has been a standard step in the processing of land seismic data for many years, especially in the preparation of pre-stack data for AVO analysis and inversion. Despite the fact that this type of process is in such common use, we believe that there is a basic problem…
