This document summarizes the 10 years of expertise of Steen Petersen in integrated earth modeling. It discusses constructing multi-scale, multi-dimensional earth models through distance fields to property distributions. It provides examples of using these models to simulate geological structures and perturbations. The implementation is through Matlab software to easily share models and add functionality. The modeling fills a gap in standard interpretation software and is used for feasibility studies.

1. Ten years of expertise in
integrated earth model
construction and simulation
Steen A. Petersen
In close collaboration with:
Gerrit Toxopeus
Technical University Delft
Susanne Lund Jensen Simula Research Laboratory Oslo
1-
GEUS (Geological Survey of Denmark and Greenland)

2. Integrated earth modelling
Drilling
performance
Geological
data
Well data
Realization
buffer
Integrated
Surface data Earth Production
Model
Characteristics:
Multi-purpose
Visualisation
Multi-scale
Editing
Multiple-dimension
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3. Filling space by interfering distance fields
Common practise: Our approach:
Property spanned between Property depends on distances to
geometries several geometries
P(x) = F(p(di(x)))
Distances exist
in any space of
Dimension > 0
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4. Distance fields (examples)
2&3D distance fields of parametric geometries (1&2 parameters)
(Petersen, S.A., Hjelle, Ø., Jensen, S.L, 2008, EAGE Conf & Techn.Exh.)
Axial
direction
Concentric Similar
deformation deformation
Distance field reflects modulus/rheology Distance fields in action
Alaei, B, Petersen, S.A., 2007, Petr. Geos. 13(3)
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5. Perturbation in geometry and geological style
Oseberg East
Real data Synthetic Synthetic
Draping (left) vs onlapping
overburden (right) Draping Onlapping
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6. Dissolution of anhydrites - Kharyaga
Undulating surface
used to define
dissolved zones anhydrite
Surface seismic section
indicating position of
remaining anhydrite dissolution
anhydrite
Model I: Synthetic
Thick anhydrite (50m)
Model II: Synthetic
Thin test suggests 20 m
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7. Dolomitisation of Carbonates-artificial structure
Plume associated with
fault. Lateral distribution
depends on distance field
and porosity.
Dolomitisation appears to
blur the seismic expression
of fault.
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8. Combining induction log and surface seismic
Tilt perturbation
Reflection
seismic
Real seismic Synt (-.5) Synt (0) Synt(+.5)
Acoustic
Impedance
One model
Two realizations
Resistivity
0.4 0.4 0.4
Apparent
?? 0.2 0.2 0.2 Resistivity
00 400 800 00 400 800 00 400 800
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9. Gas out of solution – Troll (4D)
4D signal revealed an
unexpected additional
Abormal 4D signal feature.
Normal 4D signal
Impedance contrast
OWC between vintages
Diff. due to gas
Reproduction of 4D
signal
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10. Implementation
Integrated earth modelling operates on Matlab (“Compound”)
 Easily distributed and maintained internally
 Invites colleagues to implement add-ons
 Extra functionality via the net (“global support”)
Filling a gap in standard interpretation software
 50 % technical services
 Key instrument in (what if) RD feasibility studies
Trends
 Moving downhole, production, EM, potential field
 Complex geometries (ex. non-parametric surfaces)
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11. 11 - Classification: Internal 2010-05-03