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Gregory N Green

The geologic map was created in GSMAP at Socorro, New Mexico by Orin Anderson and Glen Jones and published as the Geologic Map of New Mexico 1:500,000 in GSMAP format in 1994. This graphic file was converted to ARC/INFO format by Greb Green and GlenJones and released as the Geologic Map of New Mexico in ARC/INFO format in 1997.
The paper version of The geology of the Challis 1°x2° quadrangle, was compiled by Fred Fisher, Dave McIntyre and Kate Johnson in 1992. The geology was compiled on a 1:250,000 scale topographic base map. TechniGraphic System, Inc. of Fort Collins Colorado digitized this map under contract for N.Shock. G.Green edited and prepared the Challis digital version for publication as a geographic information system database. The digital geologic map database can be queried in many ways to produce a variety of geologic maps.
This geologic map was prepared as a part of a study of digital methods and techniques as applied to complex geologic maps. The geologic map was digitized from the original scribe sheets used to prepare the published Geologic Map of Colorado (Tweto 1979). Consequently the digital version is at 1:500,000 scale using the Lambert Conformal Conic map projection parameters of the state base map. Stable base contact prints of the scribe sheets were scanned on a Tektronix 4991 digital scanner. The scanner automatically converts the scanned image to an ASCII vector format. These vectors were transferred to a VAX minicomputer, where they were then loaded into ARC/INFO. Each vector and polygon was given attributes derived...
Crushed stone and sand and gravel are the main types of natural aggregate used in the United States. Aggregate is used in nearly all residential, commercial, and industrial building construction, and in most public works projects including roads and highways, bridges, railroad and light rail beds, airports, water and sewer systems, and tunnels. Much of the infrastructure built during the 1950s and 1960s has deteriorated to a point that requires extensive repair or replacement. All this construction requires enormous amounts of aggregate. In Colorado, for example, nearly 45 million tons of aggregate, or about 12 tons per person, were produced during 1994.
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