Changes

==The database==

==The database==

Data to the development geologist means many things. First, it means well data, including, but not limited to, well locations, header information (such as operator, year, total depth, status, elevation, and API gravity), deviation surveys, formation tops, fault cuts, results of drill stem tests and production tests, core data, and a host of calculated values such as isochore, true vertical depth, true stratigraphic thickness, and so on. Equal in importance is log information, including curves or traces, logging parameters such as mud type and resistivity, and analysis parameters such as formation water resistivity or cementation and saturation exponents. In some projects, surface geology is of great importance, consisting of bed attitudes and surface expression of contacts and faults. Seismic data can be critical, including time cross sections with interpreted horizons that need to be tied to the well control using an accurate interval velocity model. The geologist may also deal with periodic or cumulative production data by well, lease, or field. Also, the interpretation process generates new data elements, including zone average [[porosity]], net pay, and [[hydrocarbon]] pore feet.

Data to the development geologist means many things. First, it means well data, including, but not limited to, well locations, header information (such as operator, year, total depth, status, elevation, and [[API gravity]]), deviation surveys, formation tops, fault cuts, results of drill stem tests and production tests, core data, and a host of calculated values such as isochore, true vertical depth, true stratigraphic thickness, and so on. Equal in importance is log information, including curves or traces, logging parameters such as mud type and resistivity, and analysis parameters such as formation water resistivity or cementation and saturation exponents. In some projects, surface geology is of great importance, consisting of bed attitudes and surface expression of contacts and faults. Seismic data can be critical, including time cross sections with interpreted horizons that need to be tied to the well control using an accurate interval velocity model. The geologist may also deal with periodic or cumulative production data by well, lease, or field. Also, the interpretation process generates new data elements, including zone average [[porosity]], net pay, and [[hydrocarbon]] pore feet.

These data types are stored in some form of a database, which can range from a simple spreadsheet or application-specific custom files to powerful relational database management systems. The data are entered into the database by one of four methods: (1) direct keyboard entry of text or numerical values; (2) digitizing from a map, seismic section, or log print; (3) extracting or downloading from another computer system followed by reformatting (if necessary) and direct entry as digital data; or (4) as derived or computed data stored back into the database by an application program. The more powerful databases provide utilities for search and retrieval, sorting, reporting and statistical analysis, and interfaces into applications.

These data types are stored in some form of a database, which can range from a simple spreadsheet or application-specific custom files to powerful relational database management systems. The data are entered into the database by one of four methods: (1) direct keyboard entry of text or numerical values; (2) digitizing from a map, seismic section, or log print; (3) extracting or downloading from another computer system followed by reformatting (if necessary) and direct entry as digital data; or (4) as derived or computed data stored back into the database by an application program. The more powerful databases provide utilities for search and retrieval, sorting, reporting and statistical analysis, and interfaces into applications.