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: Rock Physics, Well Logs and Reservoir Geophysics:
Gulf Coast and Gulf of Mexico
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 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 to obtain fluid saturation, porosity, lithology and 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), and other seismic attributes as needed.
The primary 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.
Figure 1. Generalized Seismic Petrophysics Workflow.
End_Page 17---------------
Examples show the effects of fluid saturation and porosity on
seismic response in wells from the Texas and Louisiana Gulf
Coast and the offshore GOM. Bad log data
and mud filtrate invasion
effects will also be discussed.
End_of_Record - Last_Page 19---------------