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The major task of the geologist has always been to make maps, and this is where the first computer applications were developed and where the greatest progress has been made in refining techniques (see [[Contouring geological data with a computer]]. Computer-assisted map making can be merely posting values from the database on a basemap for hand contouring, or it can make use of one of the many specialized algorithms to compute a grid and contour that grid automatically. An intermediate approach is to digitize hand-drawn contours and compute a grid that exactly models the geologist's interpretation. The gridding step is desirable because it allows mathematical operations between surfaces (such as computing an isopach from two structure grids), volumetric reserve calculations, and three-dimensional perspective views of the surfaces, which are practically impossible to do by hand.

The major task of the geologist has always been to make maps, and this is where the first computer applications were developed and where the greatest progress has been made in refining techniques (see "[[Contouring geological data with a computer]]". Computer-assisted map making can be merely posting values from the database on a basemap for hand contouring, or it can make use of one of the many specialized algorithms to compute a grid and contour that grid automatically. An intermediate approach is to digitize hand-drawn contours and compute a grid that exactly models the geologist's interpretation. The gridding step is desirable because it allows mathematical operations between surfaces (such as computing an isopach from two structure grids), volumetric reserve calculations, and three-dimensional perspective views of the surfaces, which are practically impossible to do by hand.

Second to mapping, but closely tied to it, is log analysis (see “[[Log analysis applications]]”). The computer can help by plotting multiple runs, curve types, and text information onto a composite log, or it can compute water saturation curves from input curves using the Archie equation or more complex variants of it. Crossplots of any curve against any other curve (such as a Pickett plot) can be generated. These types of analyses are not restricted to a single well. With the proper application program, an entire field study can be processed, complete with field-wide crossplots by zone. Often the output data from the log analysis process is imported into the mapping package to be contoured.

Second to mapping, but closely tied to it, is log analysis (see “[[Log analysis applications]]”). The computer can help by plotting multiple runs, curve types, and text information onto a composite log, or it can compute water saturation curves from input curves using the Archie equation or more complex variants of it. Crossplots of any curve against any other curve (such as a Pickett plot) can be generated. These types of analyses are not restricted to a single well. With the proper application program, an entire field study can be processed, complete with field-wide crossplots by zone. Often the output data from the log analysis process is imported into the mapping package to be contoured.

Geophysical applications round out the big three (see Part 7). A basic tool in the kit is generation of [[synthetic seismograms]] from input sonic and density log data (which should be integrated with the log analysis database). Interpretation workstations for two-dimensional and three-dimensional seismic data make the geoscientist's job easier by displaying the raw data in flexible views, assisting the picking of horizons and storing the interpretations in a common database for mapping. Seismic modeling in one, two, or three dimensions can help test hypotheses of structural or stratigraphic interpretations. There are also applications for potential fields modeling, including gravity, [[magnetics]], and [[electrical methods]].

Geophysical applications round out the big three (see "[[Geophysical methods]]"). A basic tool in the kit is generation of [[synthetic seismograms]] from input sonic and density log data (which should be integrated with the log analysis database). Interpretation workstations for two-dimensional and three-dimensional seismic data make the geoscientist's job easier by displaying the raw data in flexible views, assisting the picking of horizons and storing the interpretations in a common database for mapping. Seismic modeling in one, two, or three dimensions can help test hypotheses of structural or stratigraphic interpretations. There are also applications for potential fields modeling, including gravity, [[magnetics]], and [[electrical methods]].

Many of the remaining items listed in <xref ref-type="table" rid="GeologyWorkstationtbl1">Table 1</xref> are simply programs to display specific geological data types in traditional forms expected by the geologist. A rapidly growing area is geological modeling, which includes basin and maturation modeling, plate tectonic reconstruction, and cross section reconstruction and balancing. Certainly the list will grow as new ways are found for the computer to assist the geologist.

Many of the remaining items listed in <xref ref-type="table" rid="GeologyWorkstationtbl1">Table 1</xref> are simply programs to display specific geological data types in traditional forms expected by the geologist. A rapidly growing area is geological modeling, which includes basin and maturation modeling, plate tectonic reconstruction, and cross section reconstruction and balancing. Certainly the list will grow as new ways are found for the computer to assist the geologist.