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Charles Ward Holmes

Publications and source records attributed to Charles Ward Holmes.

9 recordsLinked to original sources
USGS1978

Virgin Islands sand resource study

The depletion of sand resources in the Virgin Islands has necessitated the search for more economical supplies. The dynamic processes which produce sand in the nearshore environments are very slow, and removal of this material would cause a depletion of beaches upon which the island economy is predicated. A search for offshore sources was begun in September 1977. This program was set up for three levels of activity. The first was a broad survey of the intershelf area; the second was a detailed investigation of target areas; the third phase, a study of the sediment dynamics, is presently underway. As a result of the first survey, seven target areas were found. Three of these were examined in detail during the second phase, which showed that two areas contain significant deposits of sand. The 'double' deposit on the southwestern coast of St. Thomas contains an estimated 30x10 6 cubic meters of fine sand (0.3-0.5 mm). In the central area, a deposit near Buck Island contains an estimated 12x10 6 cubic meters of material. The sand in the second area is slightly coarser. The textural signature of these deposits is very close to that of the sand found on the beaches, which has been used in the past for construction. Studies are continuing to determine the sediment rates and budget of the shelf region.

Open-File Report↗
USGS1972

Distribution of selected elements in surficial marine sediments of the northern Gulf of Mexico continental shelf and slope

Analyses for barium, beryllium, boron, calcium, cobalt, chromium, copper, iron, lanthanum, magnesium, manganese, molybdenum, niobium, nickel, lead, scandium, tin, strontium, titanium, vanadium, yttrium, zinc, and zirconium were performed on 1,304 sediment samples from the continental shelf and slope of the northern Gulf of Mexico. Approximately 40 percent of the samples were collected in two relatively small regions, one seaward of Galveston, Texas, between long. 94° and 95° W. and the other around the Dry Tortugas on the south Florida shelf. The is remaining samples represent a broad reconnaissance survey extending from the Rio Grande to the Florida Keys.

Open-File Report↗
USGS1971

Geology of the insular shelf south of St. Thomas and St. John, U.S. Virgin Islands

A reconnaissance study has been made of the geology of the insular shelf south of St. Thomas and St. John, Virgin Islands. High-resolution seismic-reflection profiling reveals that a buried northeast-southwest striking bedrock ridge controls the shallow structure of the eastern portion of the shelf. This ridge is thought to be related to the Virgin Islands pluton farther north. Bedrock in the western shelf portion is more deeply buried and is thought to be a flatter terrain, probably lithologically similar to rocks exposed on St. Thomas. The sediment cover appears to consist principally of carbonate grains in the sand-size range. This sand is covered to various degrees by carbonate nodules at depths below about 34 m, but at shallower depths the nodules are not present. Three large areas of sandy bottom were mapped 1) west of Brewers Bay, 2) near Buck Island, and 3) off south-central St. John. Variations in the amounts of land-derived particles, organic matter, and silt/clay sized material were mapped in these bodies.

Open-File Report↗