Advantages Of Computer Modelling

I. Introduction

Ever since computers first developed, they have performed numerous tasks that have made life a little easier and more comfortable for us. The first computers were room-sized monstrosities that occupied several rooms. These first computers were made by the military for military applications, in particular for calculating ballistic and trajectory data. But in less than 50 years computers have undergone a remarkable change not only in its capabilities but also in its applications and use. Nowadays, the computer is viewed as a household appliance, serving a number of functions, from word processing to communicating through the internet. A great leap indeed.

And through its development the computer finally made its way into the world of geology. Here, the computer's ability to perform tasks and calculations quickly has helped the geologists tremendously. Because of its speed it is able to perform the numerous calculations that geologists in the past were forced to do by hand. As data manipulation became simplified it gave geologists more ease in analysis of their data.

Until now, geoscientists have had to be content to view a 3-D data in the 2-D environment of a ccomputer screen, which prohibits natural interaction with the data. At the visualization facilities coming into gue today, however, supercomputers centers that are sprouting over the industry landscape, following relatively longtime usage in the automotive and space industries ( Durham, 1999).

As technology continues to evolve, the use of the computer to a geologist also continue to change. With the advancements in computer technology, computers are now capable of generating 3-D Models. But what is 3-D? 3-D, which is also called STEREOSCOPIC, is based on the fact that humans perceive depth by viewing with both eyes. In the 3-D process, two lenses, one representing the left eye and the other the right are spaced about 2 1/2 inches (6.3 cm) apart, the same as the separation between a person's eyes. The resulting images are simultaneously projected. The viewer actually sees the images separately but perceives them in three dimensions because, for all practical purposes, the two slightly different images are fused together instantly by his mind. But a 3D model is different in that the image generated is already a solid 3D model. Meaning, that it is not necessary to trick the mind into seeing something in 3D, because the image generated is already 3-dimensional (Encyclopedia Britannica 1999).

So, basically a 3-D image is picture that appears solid because our mind is tricked into perceiving it as 3-dimensional. While, a 3-D Solid Model is an actual representation of an object in 3-dimensions.

Three-dimensional modeling and reservoir visualization tools are increasingly used to add value to heavy oil prospects (Major, 1999).

Now we shall discuss several basic definitions in computer applications. This is so that some basic computer definitions can be clarified and their nature better understood. The three basic aspects of computers that are going to be discussed will namely be: computer graphics, computer simulation, and virtual reality. The primary reason that these aspects will be discussed is because these three elements are what constitute, a 3D Solid Geology Model. Although, it is to be noted that virtual reality, is an aspect of this new technology that could be said is an option. The first two elements mentioned are in by themselves capable of generating a 3D Solid Model. Virtual reality is an element that if included gives a user the ability for greater scrutiny and analysis of a model. This is because it allows a person to "immerse" himself in the system that is being analyzed. But, unless a system requires such a detailed analysis then a solid 3D model should suffice.

II. Elements of a 3-D Solid Geology Model

A. Computer Graphics

Computer graphics, is the use of computers to produce pictorial images. These images may either be printed documents or animated motion pictures, but the term computer graphics refers particularly to images displayed on a video display screen, or display monitor.

A computer-graphics system consists basically of a computer to store and manipulate images, a display screen, various input and output devices, and a graphics software package--i.e., a program that enables a computer to process graphic images by means of mathematical language. These programs enable the computer to draw, color, shade, and manipulate the images held in its memory.

Programs that enable a user to draw, color, shade, and manipulate an image on a display screen are called Graphics software programs. With its aid a picture can be drawn or redrawn onto the screen with the use of a mouse, a pressure-sensitive tablet, or a light pen. Other preexisting images on paper can be scanned into the computer through the use of scanners, digitizers, pattern-recognition devices, or digital cameras. Frames of images on videotape also can be entered into a computer. Various output devices have been developed as well; special programs send digital data from the computer's memory to a film recorder, which prints the image on paper or on photographic film. The computer can also generate hard copy by means of plotters and laser or dot-matrix printers.

Also, there are two methods by which pictures are stored and processed in a computer's memory. The two methods: raster graphics and vector graphics. Raster-type graphics maintain an image as a matrix of independently controlled dots, while vector graphics maintain it as a collection of points, lines, and arcs. Raster graphics are now the dominant computer graphics technology. But despite the dominance of raster graphics it also has a disadvantage to it, its main disadvantage is that the images are subtly staircased, meaning that diagonal lines and edges appear jagged and less distinct when viewed from a very short distance. A corollary of television technology, raster graphics emerged in the early 1970s and had largely displaced vector systems by the '90s.

B. Computer Simulations

Now we shall define what a computer simulation is. And what it contributes to the making of a 3D Solid Model. A computer simulation is the use of a computer to represent the dynamic responses of one system by the behavior of another system modeled after it. A simulation uses a mathematical description, or model, of a real system in the form of a computer program. This model is composed of equations that duplicate the functional relationships within the real system. When the program is run, the resulting mathematical dynamics form an analog of the