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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.