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Willard E. Davis

Publications and source records attributed to Willard E. Davis.

4 recordsLinked to original sources
USGS1983

Aeromagnetic map of the West Clear Creek roadless area, Coconino and Yavapai Counties, Arizona

The West Clear Creek Roadless Area lies within the Coconino National Forest in central Arizona (fig. 1) and includes parts of Yavapai and Coconino Counties. Camp Verde, the nearest population center, is approximately 7 miles (11 km) west of the area. West Clear Creek canyon begins on the east at the confluence of the incised gorges of Willow Valley and of Clover Creek and is joined toward the west by Black Mountain Canyon. The canyon of West Clear Creek is very rugged; in several places it is more than 1,900 ft (580 m) deep. Creek elevation ranges from 6,100 ft (1,860 m) near the junction with Clover Creek to 3,200 ft (975 m) at the mouth of the canyon. The elevation of peaks and ridges near the canyon range from 4,000 ft (1,220 m) to 7,000 ft (2,135 m). Uplands at the head of Willow Valley and Clover Creek reach elevations up to 7,100 ft (2,165 m) above sea level. The greater part of the surface is underlain by late Tertiary volcanic rocks, mainly alkali olivine basalts. These overlie Lower Per i an sedimentary rocks consisting mostly of dolomite, limestone, and sandstone strata that dip gently westward. Late Tertiary and Quaternary sedimentary rocks and deposits mantle several ridges (terrace gravels) and cover basalt flows in Verde Valley at the west end of the area (Verde Formation). Quaternary alluvial deposits occur in the main West Clear Creek drainage and its larger tributaries at the west end of the area.

Arizona↗
USGS1957

Gravity prospecting for chromite deposits in Camaguey Province, Cuba

Detailed gravity surveys were made in Camaguey Province, Cuba, as part of a systematic exploration program conducted by the U. S. Geological Survey on behalf of the General Services Administration to locate deposits of refractory-grade chromite. During the period August 4, 1954, to April 5, 1956, a total of 41,921 gravity stations were established in nine areas embracing about 11.8 square miles in the Camaguey chromite district. The results of the surveys were used in connection with information obtained in geologic investigations to guide exploratory drilling.Gravimeters with low scale constants were used in making measurements sufficiently accurate to delimit anomalies as small as 0.5 gravity unit. The measurements were made over 20 X 40 and 30 X 60 meter grids and at stations 20 and 30 meters apart, respectively, along intermediate traverses in anomalous areas. Gravity differences were determined by single observations at individual stations, observing base stations hourly, and re-observing a few stations to check drift and accuracy of measurement. About 11 percent of the stations established had to be re-run because of errors in closure, microseisms, and instrument trouble.A large number of anomalies were found and evaluated according to geology, areal extent, and gravity relief. Depths to disturbing hypothetical bodies were computed to guide drilling. Test drilling of 106 positive anomalies revealed that ten features overlie deposits of chromite and 89 occur over bodies of other dense materials. The other seven anomalies were not explained by materials found in drilling. Core drilling on five of the chromite deposits revealed about 236,000 tons of chromite. An additional estimated 12,000 tons are contained in three deposits which were not blocked out. No estimate was made of the tonnage in two small deposits.

Camaguey↗