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J. B. Rapp

Publications and source records attributed to J. B. Rapp.

28 records · Page 2Linked to original sources
USGS1982

Aliphatic Hydrocarbons in Surface Sediments of Willapa Bay and Grays Harbor, Washington

Willapa Bay and Grays Harbor are two adjacent estuaries along the coast of Washington state. Willapa Bay is a recreational area minimally affected by industry; Grays Harbor, on the other hand, is moderately industrialized. Aliphatic hydrocarbons in surface sediments from these two estuaries reflect the differences in human activities. For example, the mean concentration of aliphatic hydrocarbons for seven stations in Willapa Bay is 1,000 ?g/g (relative to organic carbon) while in Grays Harbor this mean concentration for six stations is 1,900 ?g/g. The difference is attributed mainly to the greater urban and industrial pollution in Grays Harbor. The gas chromatographic records of aliphatic hydrocarbons also reflect the extent of hydrocarbon pollution by the presence of a chromatographically unresolved mixture of hydrocarbons. This kind of mixture is more evident in sediments from Grays Harbor, and in both estuaries it is more concentrated in sediments collected nearest to urban centers.

Open-File Report↗
USGS1979

Biogenic and thermogenic gas in gas-charged sediment of Norton Sound, Alaska

Chemical and isotopic compositions of sediment gas from Norton Sound have been determined for near-surface, gas-charged sediments at two sites identified in acoustic profiles and bottom observations. At one site air-driven vibracorer penetrated sediment saturated with methane. The isotopic value suggests that the methane originated from active biological processes operating on peat in the top 4 m of sediment. At the other site, characterized by a large subsurface acoustic anomaly , smaller near-surface acoustic anomalies and active seepage of gas, the vibracorer obtained sediment saturated with gas composed of 98% CO2. Associated with the CO2 are minor concentrations of petroleum-like light hydrocarbons. The carbon isotopic compositions of CO2 and methane along with the chemical distribution of gaseous hydrocarbons indicate that at this site these gases are derived from thermal processes operating at depth in Norton Basin. Apparently CO2 from the decarbonation of marine limestone acts as a carrier for hydrocarbon gases that have been generated from organic matter buried in the basin. The gases reach the surface by faults and escape at the seafloor as a submarine seep. The presence of near-surface gas-charged sediment in Norton Sound reduces the stability of the seafloor. Areas where sediments are charged with gas may pose potential hazards for engineering developments.

Alaska↗
USGS1975

Short chain aliphatic acid anions in oil field waters and their contribution to the measured alkalinity

High alkalinity values found in some formation waters from Kettleman North Dome oil field are due chiefly to acetate and propionate ions, with some contribution from higher molecular weight organic acid ions. Some of these waters contain no detectable bicarbonate alkalinity. For waters such as these, high supersaturation with respect to calcite will be incorrectly indicated by thermodynamic calculations based upon carbonate concentrations inferred from traditional alkalinity measurements

Geochimica et Cosmochimica Acta↗
USGS1974

The chemical composition and estimated minimum thermal reservoir temperatures of the principal hot springs of northern and central Nevada

Fifty-five of the principal hot springs in northern and central Nevada have been sampled for chemical analyses. Major element constituents, sodium, potassium, calcium, and silica suggest minimum thermal-aquifer temperatures of 140°C or more at 16 of the hot spring complexes. At least five of the hot springs issue mixed waters which may indicate thermal-aquifer temperatures significantly lower than the true thermal-aquifer temperature. Sodium is the principal cation in almost all the spring waters. Four springs in northern Nye County and adjacent Eureka County have approximately equal amounts of sodium and calcium. Bicarbonate is the principal anion in most of the spring waters. However, the sampled hot springs on the western edge of the State have chloride as the principal anion. A diffuse zone of bicarbonate chloride waters with or without sulfate separates the chloride and bicarbonate regions.

Nevada↗
USGS1973

Silica-carbonate alteration of serpentine: Wall rock alteration in mercury deposits of the California Coast Ranges

Chemical, isotopic, and thermodynamic properties have been measured of CO 2 -rich ground waters in the central California Coast Ranges. The acidic CO 2 -rich waters react with serpentine to form silica-carbonate rock, the host rock of many mercury deposits in the Coast Range of California. In part the waters are of a metamorphic origin and in part the waters are locally derived meteoric waters. The CO 2 is entirely derived from metamorphic reactions at depth. Depending on the relative importance of several reactions, the relative abundances of silica and carbonate minerals vary in the silica-carbonate rock. If the CO 2 -rich fluids react directly with peridotite or dunite, massive magnesite deposits may form. © 1973 Society of Economic Geologists, Inc.

California↗