Ifp Energies Nouvelles

Institut Francais Du Pe'trole

Institute Francais Du Petrole

Michel Leger

Vincent Clochard

Vincent Richard

Fr&eacute;d&eacute;ric Dumont

Laurent Grizon

Pierre-Yves Dequirez

A method of constructing a geological model of a subterranean formation formed of at least two sedimentary beds is described. Based on measurements of the geometry of boundaries of beds of the subterranean formation carried out on a grid, values of geometry of each bed at any point of the grid are calculated according to at least the steps of defining a succession of coarser and coarser grids, constructed based on the grid of interest; proceeding from the coarsest grid to the grid of interest, determining the geometry of the boundaries of each bed by solving an inverse problem initialized with the result obtained for the previous coarser grid. Next, constructing the geological model based on the completed geometry of each boundary of beds on the grid of interest.

Method of constructing a geological model

The invention is a method of monitoring an underground formation into which a gas is injected or from which a gas is produced, by a stratigraphic inversion of seismic data with anamorphosis of impedances. Pre-injection and post-injection seismic data are acquired. A pre-injection seismic impedance cube IPis determined by a stratigraphic inversion of the pre-injection seismic data. An anamorphosis function &#x3b1; is defined by a function comprising a positive lower limit B, an upper limit B, an identity interval defined between limits Band B, with B&#x3c;B&#x3c;B&#x3c;B. A value for each limit B, B, Band Bis associated with each cell of the cube. Post-injection seismic impedances IPare determined by a stratigraphic inversion of the post-injection seismic data wherein the anamorphosis function &#x3b1; is applied to seismic impedances IP. The gas is located within the zone by identifying the cells where IP&#x3c;IP

Method of monitoring a geological gas storage site by stratigraphic inversion of seismic data

A method for 3D modeling of the impedance of a heterogeneous medium from recorded data corresponding to waves coming from the heterogeneous medium (such as a subsoil zone), in response to (for example elastic or electromagnetic) waves transmitted therein, and from an a priori 3D model of this heterogeneous medium, knowing the position of various impedance discontinuities of the medium, and after stratigraphic interpretation is disclose. The method comprises constructing a 3D geometric model comprising several foliated volumes (such as sedimentary units foliated by the deposition isochrones) with definition of the different sheets, constructing an a priori impedance model from this geometric model and from a plurality of impedance measurements taken at various depths of the heterogeneous medium (in a well for example), selecting a covariance model (exponential for example) along the sheets of the foliated volumes, and forming the optimum model by recorded data inversion using the a priori impedance model. The method can be used notably for studying the configuration of hydrocarbon reservoirs for example.

Method for 3D modelling of the impedance of a heterogeneous medium

The method relates to an optimizing method for determining the optimum shape of plates such as sheets of sheet metal, panes of glass, or other thin objects designed in particular to retract completely in order to leave a clear opening. To simplify the use of shaped plates that have already been predesigned, they are modified such that their shapes coincide substantially with a 'screwable' surface chosen from the wide variety of existing surfaces that meet screwability criteria and can hence move in the space without changing position, except for their edges. Implementation of the method allows the various constraints that may exist in the design of such plates to be met.

Growing community of inventors

Rueil-Malmaison, France

Michel Leger