PGrids (Polyhedral Grids) : a new 3D geometric support for geomodelling

Stéphane Conreaux and Bruno Levy. ( 1999 )
in: Proc. $19^{th}$ Gocad Meeting, pages 164-174, ASGA

Abstract

A model may be considered under three different aspects, which are the connectivity, corresponding ta the way an object is connected ta neighbouring object in the model; the subdivision, decomposing the object into elementary elements called cells (vertices, edges, polygons, polyhedra, ... ) and the embedding, representing the geometry and properties attached to the objects. In GOCAD, a 3D Model is defined as a partition of space. The inner space of the model is subdivided into regions. Each region is initially empty but can be filled with a 3D support for representing properties. To store these properties, volumic objects such as tetrahedralized volumes, channels, SGrid or other supports, are defined as a sub-partition of the 3D regions of the model. As such, we present in this paper the notion of unstructured polyhedral grid (PGrid). This paper introduces as well a method for constructing such object to represent stratigraphic structures. It is shown how unconformities are dealt with, enabling non neighbourhood connectivities to be replaced by regular connectivities of the polyhedra.

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    BibTeX Reference

    @inproceedings{RUNKJRM7,
     abstract = { A model may be considered under three different aspects, which are the connectivity, corresponding ta the way an object is connected ta neighbouring object in the model; the subdivision, decomposing the object into elementary elements called cells (vertices, edges, polygons, polyhedra, ... ) and the embedding, representing the geometry and properties attached to the objects. In GOCAD, a 3D Model is defined as a partition of space. The inner space of the model is subdivided into regions. Each region is initially empty but can be filled with a 3D support for representing properties. To store these properties, volumic objects such as tetrahedralized volumes, channels, SGrid or other supports, are defined as a sub-partition of the 3D regions of the model. As such, we present in this paper the notion of unstructured polyhedral grid (PGrid). This paper introduces as well a method for constructing such object to represent stratigraphic structures. It is shown how unconformities are dealt with, enabling non neighbourhood connectivities to be replaced by regular connectivities of the polyhedra. },
     author = { Conreaux, Stéphane AND Levy, Bruno },
     booktitle = { Proc. $19^{th}$ Gocad Meeting },
     pages = { 164-174 },
     publisher = { ASGA },
     title = { PGrids (Polyhedral Grids) : a new 3D geometric support for geomodelling },
     year = { 1999 }
    }