Geometrical modelling and graphics display of stratigraphic orebodies.

In this research project the author introduces the use of geometrical modelling techniques alongside geostatistical methods to model a stratigraphic orebody and to present a graphics display
system developed as a fIrst step towards a general integrated system for computer aided design and
planning in mining. Geometrical modelling techniques and geostatistical methods are combined to carry out the process of modelling a stratigraphic orebody. From a mining point of view, there are two main features of interest in a stratigraphic ore-body:
a-The modelling of the geometry of the orebody.
b- The modelling (estimation) of the physical properties (grades, etc ... ) of the orebody.
The first feature is the subject of this research project.
Modelling methods and techniques developed elsewhere and for different applications, such as Computer Aided Design, have been applied successfully to model the geometry of stratigraphic orebodies. The modelling process consists of the applications of surface modelling techniques to represent the hangingwall and the footwall of the stratigraphic orebody and thereby to produce the space where the physical properties are geostatistically to be estimated. The graphics display system is presented to highlight the use of computer graphics techniques to communicate graphically all sorts of information concerning the modelling of stratigraphic orebodies and also to display the end product of the modelling process, such as cross-sections, plane-sections, wireframe and solid models of the orebody. The graphics system itself is part of a computer based system for mine design and planning similar to computer aided design systems used mainly in the manufacturing industry. The presentation of the research project in this thesis started by the review of the literature of some existing ore reserves estimation methods in the mineral industry, particularly geostatistical methods. Then an overview and the scope of this research project have been given. The second chapter describes the type of data which could be encountered while building a geometrical model of a stratigraphic orebody and a description of data from a nickel vein deposit used as a case study for this research project. The accumulations have been estimated geostatistically subject to geometrical control. The geometrical control concept and surface modelling techniques are presented in chapter three together with the numerical application of modelling a nickel vein deposit using two different surface modelling techniques. Chapter four describes the graphics display system developed to display several geometric features of stratigraphic orebodies in two and three dimensions. The summary of this research project and some concluding remarks are given in chapter five