Rock Physics software

1. SeisTool
Seismic - Rock Physics Tool
August 2017
info@traceseis.com

2. SeisTool: Seismic – Rock Physics Tool
Supports Exploration and Development Geoscientists in identifying or
characterizing reservoir properties from seismic data. Reduces chance of
user error and increases productivity by eliminating book-keeping and
reducing display set-up time.
• Data are computed and displayed on the fly. There is no book-keeping. This results in
faster analysis and less chances of mistakes.
• Pre-defined templates reduce display set-up time.
• Parameters for a given module are input in a single GUI.
• TraceSeis’ rock physics tool does not perform petrophysical evaluations. Data input
are specific logs - rock properties, reservoir properties and target flag.
Note: The data used in this presentation consists of a well with a binary petrophysical evaluation (Vsh, Sw and f). Similar analysis could
have been done using a well with a multi-mineral analysis

3. Consists of three modules, each with three programs. The analysis and modeling modules (SeisRP and SeisMod) are based on
state of the art rock physics relationships. These support the reservoir characterization module (SeisCar) in which parameters
to compute reservoir properties from seismic (f, lithology and fluids) are estimated through linear inversion of attributes
computed from well-log or synthetic data.
SeisRP SeisMod SeisCar
• SeisRP
• SeisMod - Under development
• SeisCar - Under development
SeisTool: Seismic – Rock Physics Tool
SeisTool

4. Generalized exploration/development
workflow to estimate reservoir properties
Well-log Resolution Seismic Resolution
Compute and
evaluate
attributes
SeisRP
Sensitivity
analysis
SeisMod
Determine
optimum
attributes
SeisCar
Compute
lithology and
porosity
cubes
Compute
probability
cubes
Attributes
from seismic
Seismic Resolution
Well-log Resolution
Petrophysics
(f, SW, lithology)
Rock
Properties
(VP, VS and r)
Simplified workflow showing the function that SeisRP, SeisMod and SeisCar have in supporting estimation of reservoir
properties using seismic data

5. • SeisRP
• Computes reflectivities and absolute and
relative properties
• Generates attributes from wireline data at
well-log and seismic resolutions in depth or
two-way-time
• Fluid substitution. Different fluids and
saturations
• SeisMod – Under development
• SeisCar – Under development
SeisRP computes reflectivities and absolute and
relative properties.
Some observations about relative properties
- Measure interval properties
- Do not require a Low Frequency Model (LFM)
- Easy to compute from AVO attributes
- Better estimation of reservoir properties (SeisCar)
Reflectivities Ip, Is Relative Properties Ip, Is
SeisTool: Seismic – Rock Physics Tool

6. SeisRP – Analysis at well-log resolution
Attributes
Absolute
Relative
Reflectivity
Absolute Relative Reflectivities
List of available attributes
Other
Petrophysics
Depth
Target Flag
SeisRP
computes reflectivities and
absolute and relative properties

7. SeisTool: Seismic – Rock Physics Tool
Analysis at seismic resolution
Wavelet QC
• SeisRP
• Computes reflectivities and absolute and
relative properties
• Generates attributes from wireline data at
well-log and seismic resolutions in depth or
two-way-time
• Fluid substitution. Different fluids and
saturations
• SeisMod – Under development
• SeisCar – Under development

8. SeisRP: Analysis at well-log and seismic resolution
Relative P-impedance
and
Relative S-Impedance
In depth at well-
log resolution
In time at seismic
resolution
(Dt = 1msec)
Reflectivity in the angle gather
shows a trough and a peak in top
and base reservoir respectively.
Relative Ip and relative Is are
interval properties
Seismic Resolution Well-log Resolution

9. SeisTool: Seismic – Rock Physics Tool
In-situ
SW = 1.0
Sands in wet reservoir
follow Gardner’s
relationship
Sands in gas
reservoir do not
follow Gardner’s
relationship
• SeisRP
• Computes reflectivities and absolute and
relative properties
• Generates attributes from wireline data at
well-log and seismic resolutions in depth or
two-way-time
• Fluid substitution. Different fluids and
saturations
• SeisMod – Under development
• SeisCar – Under development

10. Fluid Properties
Reservoir fluids’ composition (GOR, API, SG,
salinity) and environmental variables (pressure
and temperature) are used to compute bulk
moduli and density of fluids.
Properties for three fluids are computed: in-
situ and replacement hydrocarbons and brine.
Depth variant or constant fluid properties can
be computed.

11. SeisRP – Fluid substitution. In-situ
Rel(Ip)
Rel(Is)
3 Term AVO synthetic to 45o.
Shows the “Curvature” in far angles
In-situ fluids. The AVO extracted at the red and blue horizontal lines in tracks 1 and
2 correspond to a class 4 anomaly, as observed in the plot at right

12. SeisRP – Fluid substitution. Sw = 1.0
Rel(Ip)
Rel(Is)
Water saturation = 1.0. Compare with the previous slide. The light-blue arrow in the
lower part of track 1 shows the slight time difference between the in-situ (previous
slide) and wet reservoir (this slide) associated to fluids with different velocities

13. SeisTool: Seismic – Rock Physics Tool
• SeisRP
• SeisMod – Under development
• Well-log inversion and modeling – Forward
models well-logs.
• Estimates moduli and densities of rock
constituents through non-linear inversion of
rock properties’ logs
• Computes attributes for perturbations of the in-
situ reservoir properties
• Based on effective media theory. Minimum
heuristic or empirical relationships are used
• SeisCar – Under development
Well-log Modeling
The red curves in tracks 1 and 2 are the modeled r, Vs and Vp using
the moduli and densities in the tables above. The blue lines are
measured logs
Rock properties (Vp, Vs and r) are modeled using a rock physics model
(effective media relationships) and the moduli and densities of the rocks’
constituents.
The poor fit of measured and modeled velocities (track 2) indicates that
either the model used or the selected physical properties of constituents
have to be re-considered.
In the next slide the moduli and densities of constituents are estimated
through non-linear inversion of rock properties.

14. SeisTool: Seismic – Rock Physics Tool
Well-log Inversion
The modeled curves are a close match to
the measured ones after moduli and
densities are computed through non-
linear inversion of rock properties.
Iteration #
vs
Objective Function
Once the effective moduli and densities of constituents have been
satisfactorily estimated, the reservoir properties (f, lithology and
fluids) can be modified and the rock properties’ logs (Vp, Vs and r)
modeled as if they had been acquired under the new, modified,
condition. This is the basis for the sensitivity and ambiguity
analyses.
• SeisRP
• SeisMod – Under development
• Well-log inversion and modeling – Forward
models well-logs.
• Estimates moduli and densities of rock
constituents through non-linear inversion of
rock properties’ logs
• Computes attributes for perturbations of the in-
situ reservoir properties
• Based on effective media theory. Minimum
heuristic or empirical relationships are used
• SeisCar – Under development

15. SeisTool: Seismic – Rock Physics Tool
• SeisCar – Under development
• Estimate reservoir properties through
linear inversion of attributes at well-log or
seismic resolution
• Probability analysis
• 3D Model cube
Relative lambdaRho and
relative muRho.
Log-plot and scatter plot
• SeisRP
• SeisMod – Under development

16. SeisTool: Seismic – Rock Physics Tool
SeisCar returns the relationship to
convert seismic attributes to
reservoir properties.
In this slide the analysis is done at
well-log resolution
143o coordinate rotation
• SeisCar – Under development
• Estimate reservoir properties through
linear inversion of attributes at well-log or
seismic resolution
• Probability analysis
• 3D Model cube
• SeisRP
• SeisMod – Under development
In the scatter-plot at right, the data has been rotated 143o
counter-clockwise (compare scatter-plots in this and the previous
slide).
The log-plot shows, in the third track, the result of scaling and
shifting the x-axis projection of the rotated data to get a
quantitative estimate of porosity. The equation used follows:
Similar approach would be used to estimate reservoir properties
using attributes computed from seismic.

17. Generalized exploration/development
workflow to estimate reservoir properties
Well-log Resolution Seismic Resolution
Compute and
evaluate
attributes
SeisRP
Sensitivity
analysis
SeisMod
Determine
optimum
attributes
SeisCar
Compute
lithology and
porosity
cubes
Compute
probability
cubes
Attributes
from seismic
Seismic Resolution
Well-log Resolution
Petrophysics
(f, SW, lithology)
Rock
Properties
(VP, VS and r)
Simplified workflow showing the function that SeisRP, SeisMod and SeisCar have in supporting estimation of reservoir
properties using seismic data

18. SeisTool
Seismic-Rock Physics Tool
August 2017
Click here to schedule a demo or to evaluate SeisRP
info@traceseis.com
(832) 707-6505