BONARA, M.1, A. K. PAHL1, T.
MURRAY1, A. D. GIBBS1, and T. DOOLEY2
1Midland Valley Exploration Ltd, Glasgow, UK
2University
of London: Royal Holloway, Egham, UK
Abstract: 3D
Restoration Techniques
for Strike Slip Deformation
The kinematics and analysis of strike-slip deformations are poorly understood despite their economic importance. Due to the complexity of deformation style, they represent a particular challenge for interpreter and modeller alike. In this paper we present new methodologies to enable interpreters to validate their interpretation and to assist in modelling poorly imaged parts of the structure. The approach represents a significant extension of the principal of balance and kinematic structural analysis from essentially dip slip systems to true strike slip kinematics.
The techniques used in this study apply new fault
deformation algorithms, which map deformation to the fault surface by using
a fault parallel flow algorithm. Variable 3D
shear analogous to back shear
in an overthrust terrain is used to generate shear variation in three dimensions
away from the fault surface. The algorithm has been implemented to allow
volumes on both sides of the fault to be deformed by splitting the deformation
into a two stage process for computational simplicity.
The approach has been applied to a synthetic
scaled
sand box model. A digital model of the analogue experiment was constructed
using serial 2D sections. This
3D
model was then restored using the deformation
flow approach to produce a workflow for the process and a methodology of
applying the technique to geological
data
. Sensitivity of the technique
is discussed and validated by reference to the limitations and constraints
of analogue and digital modelling techniques.
AAPG Search and Discovery Article #90928©1999 AAPG Annual Convention, San Antonio, Texas