About This Item
- Full text of this item is not available.
- Abstract PDFAbstract PDF(no subscription required)
Share This Item
The AAPG/Datapages Combined Publications Database
Houston Geological Society Bulletin
Abstract
Abstract: Use of Well Logs in Seismic Reservoir Characterization
By
Rock Solid Images,
Houston, Texas
Seismic reservoir characterization, also known as reservoir
geophysics, has evolved over the past several years into a
multi-disciplinary, business-critical function in most ED&P
organizations. Sheriff defines reservoir
geophysics as “The use of geophysical
methods to assist in delineating or
describing a reservoir or monitoring
the changes in a reservoir as it is produced.”
Reservoir geophysics is applied
across a wide spectrum of the oilfield
life cycle from discovery and early
development to tertiary recovery. One
critical part of this process is careful
analysis
and understanding of petrophysical
properties from well logs and
core data (seismic petrophysics).
This presentation will illustrate why seismic petrophysics is so important and will show how carefully constructed synthetic models can help the geoscientist interpret acoustic and elastic impedance inversion from seismic data.
Seismic petrophysics can be performed on single or multiple wells and consists of the following basic steps.
Geophysical Well Log Analysis
(GWLA)
- Collect and organize input data, reservoir conditions, and fluid properties
- Perform geophysical log interpretation for volume minerals, porosity, and fluids over entire well
- Edit logs and perform mud filtrate invasion correction (as needed)
- Generate missing curves (for
example shear wave
velocity
).
Rock Physics Modeling and Perturbations
Perturb reservoir properties using
rock physics effective medium models
and compute new Vp, Vs and density
curves.
- Fluid Saturation
- Porosity
- Lithology
- Net/gross
Synthetics
Compute synthetic seismic traces for in-situ and modeled conditions. May also include:
- AVO response
- Acoustic impedance (AI) and elastic impedance (EI)
- Other seismic attributes as needed
Examples show the effects of mud filtrate invasion effects, wellbore washouts and a bad Vshear log on seismic well tie. An example is also shown of how seismic
End_Page 27---------------
petrophysics can be used to interpret acoustic and elastic impedance inversions for oil saturation and porosity in an on-shore United States oil sand. The pricipal benefits of seismic petrophysics are improved well-to-seismic ties, improved calibration of seismic attributes to reservoir properties, and more reliable models of seismic response due to reservoir changes (vertically, laterally and temporally). These models can improve interpretation of 3D seismic data, especially acoustic and elastic impedance inversion. This improved interpretation can reduce drilling risk, enhance field productivity and ultimately increase asset value.
Note: This presentation is based on OTC paper 16921, May 2004.
End_of_Record - Last_Page 29---------------