Implémentation de méthodes de restauration équilibrée 3D

Jérôme Massot. ( 2002 )
INPL, Nancy, France

Abstract

The restoration of a geological structure is not a recent idea. Chamberlin, in 1910, was one of the first structural geologists to unfold structures on cross sections. By restoration, one has to understand the unfolding and the unfaulting of a layer or a stack of layers. The first restoration methods were performed in 2d cross-sections or in map-view because the problems are easier to solve than in 3d and because the available data were cross-sections and geological maps only. Today, thanks to the acquisition of data in 3d, volumic restoration methods can be proposed. These techniques share the same general models of deformation and are based on the prin ci pl es of material preservation and minimization of the strain induced by the restoration (retro-strain). This thesis introduces two new approaches : - the first one uses algorithms based on the parametric representation of a surface to restore a geological horizon and study the retro-strain, - the second approach explain how to restore volumic structures by interpolating the field of restoration vectors in 3D, ensuring the mass-preservation and strain-minimization principles to be verified. For these both approaches, we show how to compute the retro-strain and how to interpret this information in orcier to enhance the knowledge of the geological mo del. The success of a restoration is fully dependent of the quality of the input data assumed to be be known at current time. More generally, faults are the most diffi.cult geological objects to modelize. So, to enhance the quality of the geological model, we also propose tools to study and correct the geometry of faults and show how to use this information to improve the result of the restoration process.

Download / Links

BibTeX Reference

@PHDTHESIS{Massot02,
    author = { Massot, Jérôme },
     title = { Implémentation de méthodes de restauration équilibrée 3D },
   chapter = { 0 },
      year = { 2002 },
    school = { INPL, Nancy, France },
  abstract = { The restoration of a geological structure is not a recent idea. Chamberlin,
in 1910, was one of the first structural geologists to unfold structures on cross
sections. By restoration, one has to understand the unfolding and the unfaulting
of a layer or a stack of layers. The first restoration methods were performed in
2d cross-sections or in map-view because the problems are easier to solve than in
3d and because the available data were cross-sections and geological maps only.
Today, thanks to the acquisition of data in 3d, volumic restoration methods can
be proposed. These techniques share the same general models of deformation
and are based on the prin ci pl es of material preservation and minimization of the
strain induced by the restoration (retro-strain).
This thesis introduces two new approaches :
- the first one uses algorithms based on the parametric representation of a
surface to restore a geological horizon and study the retro-strain,
- the second approach explain how to restore volumic structures by interpolating
the field of restoration vectors in 3D, ensuring the mass-preservation
and strain-minimization principles to be verified.
For these both approaches, we show how to compute the retro-strain and how
to interpret this information in orcier to enhance the knowledge of the geological
mo del.
The success of a restoration is fully dependent of the quality of the input data
assumed to be be known at current time. More generally, faults are the most
diffi.cult geological objects to modelize. So, to enhance the quality of the geological
model, we also propose tools to study and correct the geometry of faults and show
how to use this information to improve the result of the restoration process. }
}