|
Case Studies/Technical Talks
Geotrace's technical capabilities are often showcased in case studies, presentations at trade shows or regional meetings. The most recent technical papers can be accessed below; earlier information appears in the Archives.
Adobe Acrobat Reader may be required.
 Reducing Risk in Spraberry Sands, Dawson Co., Texas - Identifying the best reservoirs with PreStack Inversion to Rock Properties (Presented at West Texas Geological Society, October 25, 2007)
Historically in West Texas simultaneous inversion of linearized AVO equations has been limited to a two-term solution, with the application and interpretation of this two-term solution limited to reflectivities. In an area of mature rocks with high velocities and subtle density variations, the application of the two-term methodology has inherent limitations in sensitivity and delineation capabilities. Furthermore, the analysis of this solution in the reflectivity domain has additional drawbacks such as ambiguity of hydrocarbon saturation and proper reservoir volumetric estimations. This paper presents a three-term approach to the simultaneous inversion for AVO, and continues through the derivation of full broadband rock properties. The application of this methodology addresses the inherent limitations of a two-term AVO inversion and reflectivity analysis by providing a more versatile solution capable of supporting many more interpretation goals. |
High
Density High Resolution Seal Capacity and Pore Pressure Prediction
from 3D Seismic Data (Presented at EAGE, June 2007)
The estimated cost associated with geopressure problems can
easily reach US$9 billion a year for the oil and gas industry.
In recent years, with the increase of day rate for drilling
rigs, semis and ships, it is more critical than ever to understand
and quantify the formation pore pressure for assessing fluid
migration, seal capacity, drilling risk, and well planning
in order to high-grade the prospects, prevent drilling hazards
and reduce cost in various exploration and production activities. |
Nile
Delta Reservoir Case Study using a Novel Broad Band Pre-stack
Seismic Inversion to Rock Properties Technique (Presented
at EAGE, June 2007)
Exploration for hydrocarbons within an onshore concession
in the Nile Delta, Egypt has been ongoing for several years.
Despite the presence of clean sand reservoirs with a good
shale cap rock and four way closures, none of the wells drilled
so far have proved to be significant hydrocarbon producers.
A pre-stack seismic inversion to rock properties study was
therefore carried out to better understand the lithology in
the area and highlight potential reservoirs. A novel technique
was used to provide the broad bandwidth essential for a successful
inversion. This paper details the results of the project |
The Power
of 3D Visualization Using Pore Pressure Data (Upstream Technology,
May 2007)
The financial and environmental consequences of exploring
and producing in basins without a proper understanding of
3D pressure cell distribution can be disastrous, from increased
drilling costs, pollution and unrealized potential to a full-scale
blowout. The oil and gas industry estimates that the annual
cost associated with these problems reaches into the billions. |
Data Integration in a War Zone (Hart's E&P, October, 2007)
Finding, managing and integrating data can be a challenge in any environment. A team recently undertook this task in war-torn Iraq. |
Turning Ray Prestack Time Migration with Raytraced Offset-Dependent Velocities (Presented at SEG, September, 2007)
Conventional prestack time migration uses RMS velocities to map input data to output samples. Raytraced traveltimes may be converted to "velocities" at a suite of offset values, and used in place of traditional RMS velocities. This provides an implementation of curved ray migration that is not only more accurate than the 4th or 6th order approximations, but is also equivalent in computational time to the conventional straight ray (2nd order) approach to time migration. |
Improving performance and accuracy of 3D Kirchhoff migration (Presented at SEG, September, 2007)
Since 3D Prestack Kirchhoff Depth Migration (KPSDM) has become one of the leading imaging tools for hydrocarbon exploration, its accurate and precise handling of the kinematical and dynamical aspects of the wavefield have become center stage to the R&D efforts worldwide. In a separate paper in this proceeding by the same author, describe a modified antialiasing filter weight that corrects for amplitude artifacts observable in earlier designs. Here we continue the efforts of developing an efficient true amplitude migration algorithm by suggesting a simplificiation of the traditional filtering done during this process that will improve the performance and precision of the results. |
A
Review of some Powerful Noise Elimination Techniques for Land
Processing (Presented at EAGE, June 2007)
Raw seismic data are often dominated by noise. Both coherent
and incoherent noise are inherent to, and a pervasive problem
of, seismic data. To facilitate proper interpretation and
analysis of the relevant structure in the subsurface, the
elimination of this noise is essential. Noise attenuation
challenges have kept the oil and gas industry, and in particular
the seismic data processing professionals, busy for many years.
We have come a long way. However, the total elimination of
this noise remains an elusive goal. |
Tomographic Velocity
Inversion (Journal of Petroleum Technology, April 2007)
Geotrace has developed its MultiScale, MultiParameter Simultaneous
Velocity Inversion Tomography technology - MuST - to obtain
3D images of geologically complex areas. |
|
