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A. S. Van Denburgh

Publications and source records attributed to A. S. Van Denburgh.

At least 19 recordsLinked to original sources

Solute erosion and chloride balance in selected river basins of the western conterminous United States

The estimated average rates of annual solute erosion in 11 important western river basins range from 180 tons per square mile (Willamette basin) to 4.2 tons per square mile (Gila basin). An average rate of 58 tons per square mile is indicated for the entire 545,000‐square‐mile area drained by the 11 rivers. The wide range in tonnage is the result of a complex of causes, among which differences in geology, gross climatic environments, and activities of man are the most important. Rates of solute erosion are highest in areas of abundant precipitation and runoff, in contrast to rates of suspended‐sediment removal, which are characteristically highest in basins subjected to only 10–15 inches of effective annual precipitation. Tonnages of chloride brought into the 11 river basins by rain and snow make up an equivalent of about 1.6 to about 17% of the chloride removed in runoff during an average year. The range of percentages reflects differences in the relative importance of oceanic and continental solute contributions. This paper is not subject to U.S. copyright. Published in 1965 by the American Geophysical Union.

Water Resources Research↗

U.S. Geological Survey ground-water studies in Nevada

Groundwater is an important natural resource in Nevada. In 1985, groundwater provided 24% of the total water withdrawn, and supplied about 40% of the State 's population. Public supply and self-supplied domestic use accounted for about 12% of the groundwater withdrawn, and self-supplied industrial and mining use was about 3%. The major issues related to groundwater in Nevada are: groundwater availability; natural and artificial groundwater recharge; underground storage of hazardous wastes; organic and inorganic trace constituents in groundwater; and geothermal groundwater systems. The U.S. Geological Survey (USGS) is actively conducting 30 hydrologic investigations in Nevada, of which 18 are related to groundwater quantity and quality. Three examples of ongoing groundwater studies by the USGS that are designed to address specific groundwater issues in Nevada are discussed: carbonate-rock aquifers in eastern and southern Nevada; groundwater quality in the Carson River basin, Nevada-California; and groundwater in Honey Lake Valley, Nevada-California. (Lantz-PTT)

Open-File Report↗

Geohydrology, aqueous geochemistry, and thermal regime of the Soda Lakes and Upsal Hogback geothermal systems, Churchill County, Nevada

A flow-routing model of the upper Schoharie Creek basin, New York, was developed and used to simulate high flows at the inlet of the Blenheim-Gilboa Reservoir. The flows from Schoharie Creek at Prattsville, the primary source of flow data in the basin, and tributary flows from the six minor basins downstream, are combined and routed along the 9.7 mile reach of the Schoharie Creek between Prattsville and the reservoir inlet. Data from five historic floods were used for model calibration and four for verification. The accuracy of the model as measured by the difference between simulated and observed total flow volumes, is within 14 percent. Results indicate that inflows to the Blenheim-Gilboa Reservoir can be predicted approximately 2 hours in advance. One of the historical floods was chosen for additional model testing to assess a hypothetical real-time model application. Total flow-volume errors ranged from 30.2 percent to -9.2 percent. Alternative methods of obtaining hydrologic data for model input are presented for use in the event that standard forms of hydrologic data are unavailable. (USGS)

Water-Resources Investigations Report↗

Preliminary hydrogeologic appraisal of selected hydrothermal systems in northern and central Nevada

Several hydrothermal systems in northern and central Nevada were explored in a hydrogeologic reconnaissance. The systems studied comprise those at Stillwater and Soda Lakes-Upsal Hogback in the Carson Desert, Gerlach, Fly Ranch-Granite Range, and Double Hot Springs in the Black Rock Desert, Brady's Hot Springs, Leach Hot Springs in Grass Valley, Buffalo Valley Hot Springs, and Sulphur Hot Springs in Ruby Valley. The investigation focused on (1) delineating of areas of high heat flow associated with rising thermal ground water, (2) determining the nature of the discharge parts of the hydrothermal systems, (3) estimating heat discharge from the systems, (4) estimating water discharge from the systems, (5) obtaining rough estimates of, conductive heat flow outside areas of hydrothermal discharge, and (6) evaluating several investigative techniques that would yield the required information quickly and at relatively low cost. The most useful techniques were shallow test drilling to obtain geologic, hydraulic, and thermal data and hydrogeologic mapping of the discharge areas. The systems studied are in the north-central part of the Basin and Range province. Exposed volcanic rocks of latest Tertiary and Quaternary age are chiefly basaltic. Basaltic terranes are generally regarded as less favorable for geothermal resources than terranes that contain large volumes of young volcanic mocks of felsic to intermediate composition. Most of the known hydrothermal systems are associated with Basin and Range faults which are caused by crustal extension across the province. An area of high heat flow centered at Battle Mountain and possibly other areas of high heat flow may be related to crustal heat sources. However, some of the hydrothermal systems studied appear to be related to deep circulation of meteoric water in areas of 'normal' regional heat flow rather than to shallow-crustal heat sources. Discharge temperatures of thermal springs in the region range from slightly above mean annual air temperature (8?-12?C at most places) to boiling or slightly hotter. Geochemical data indicate that, in the major systems, subsurface temperatures at which thermal waters equilibrate with reservoir rocks range from 150? to more than 200?C. These data also indicate that the major systems are of the hot-water type rather than the vapor-dominated type. Depths of thermal-water circulation probably range from 2 to 6 kilometres in areas of 'normal' regional heat flow (~2 heatflow units) and from 1 to 3 kilometres in areas of high heat flow (~3-4 heat-flow units) such as near Battle Mountain. Most of the heat is discharged from the hydrothermal systems studied by (1) conduction through near-surface materials heated as a consequence of thermal-water convection, (2) convection as springflow, and (3) convection as steam discharge from spring pools, vents, fumaroles, and cracks. The mate of heat discharge by radiation from warm ground and by convection as lateral ground-water outflow is believed to be small in most systems and is not estimated. Estimates of net heat discharge from the systems studied range from about 0.8 x 106 calories per second at Buffalo Valley Hot Springs to about 14 x 106 calories per second at Stillwater. These estimates represent the approximate magnitude of the excess heat discharge from the thermal areas that results from the upward convection of hot water from deep sources. Water discharges from the hydrothermal systems by springflow, evapotranspiration, steam discharge, and lateral ground-water outflow. Estimated discharges range from about 0.2 x 106cubic metres per year from the Buffalo Valley Hot Springs system to about 3 x 106 cubic metres per year from the Stillwater system. In most of the hydrothermal systems studied and, by inference, in other similar systems in northern and central Nevada, the scale for potential .commercial development for production of electricity or for other uses may be constrained by the

Open-File Report↗

Mercury in the Carson and Truckee River basins of Nevada

Upstream from major pre-1900 ore milling in the Carson and Truckee River basins, "background" concentrations of total mercury in the upper 1 to 3 inches of sand- to clay-sized stream-bottom sediment are less than 0.1 ug/g (microgram per gram). Downstream, measured concentrations were as much as 200 times the background level. Greatest concentrations were encountered in the Carson River basin within and immediately upstream from Lahontan Reservoir. Data from for the Carson River near Fort Churchill suggest that most of the mercury in the sampled bottom sediment may be present as mercuric sulfide or as a component of one of more non-methyl organic compounds or complexes, rather than existing in the metallic state. Regardless of state, this reservoir of mercury is of concern because of its possible availability to the aquatic food chain and, ultimately, to man. Among 48 samples of surface water from 29 sites in the two basins, the maximum measured total-mercury concentration was 6.3 ug/1 (micrograms per liter), for a sample from the Carson River near Fort Churchill. Except downstream from Lahontan Reservoir, most other measured values were less than 1 ug/1. (The U.S> Environmental Protection Agency interim limit for drinking water is 5 ug/1.) The total-mercury content of stream water is related to the mercury content of bottom sediments and the rate of streamflow, because the latter affects the suspended-sediment transporting capability of the stream,. Near Fort Churchill, total-mercury concentrations that might be expected at streamflows greater than those of 1971-72 are: as much as 10-15 ug/1 or more at 2,000 cfs (cubic feet per second), and as much as 10-20 ug/1 or more at 3,000 cfs. Elsewhere, expectable concentrations are much less because the bottom sediment contains much less mercury. The mercury contents of water samples from 36 wells in the Carson and Truckee basins were all less than 1 ug/1, indicating that mercury is not a problem in ground water, even adjacent to areas where stream-bottom sediment is enriched in mercury. Limited data indicate that the Carson River above Lahontan Reservoir and the reservoir itself contain only trace amounts of dissolved arsenic, cyanide, selenium, and silver. Among 17 additional trace metals analysed for on four unfiltered samples from the river above the reservoir, only six of the metals were consistently present in concentrations exceeding detection limits. Maximum measured concentrations for the six metals were: aluminum, >670 ug/1; iron, 2,500 ug/1; manganese, 1,100 ug/1; molybdenum, 15 ug/1; titanium, 110 ug/1; and vanadium, 15 ug/1. Presumably, the detected metals were associated largely or almost entirely with the suspended-sediment phase of the water samples. Selenium and silver concentrations in sampled well waters from the Carson and Truckee basins were uniformly low, with one exception--as elenium concentration of 18 ug/1 for the water of a shallow well southwest of Fallon (Public Health Service limit, 10 ug/1). The arsenic content of 15 sampled well waters ranged from 0 to 1,500 ug/1 (0 to 1.5 ppm), with seven of the values greater than 50 ug/1 (the Public Health Service limit).

Nevada↗

Interstitial brines in playa sediments

Study of several closed drainages in the Great Basin has shown that the interstitial solutions of shallow, fine-grained playa deposits store a large quantity of dissolved solids and are often more concentrated than associated lakes and ponds, except in peripheral zones of stream or ground-water inflow. These interstitial fluids, when compared with local runoff, impoundments, or spring waters, commonly have a distinctive ionic composition which sometimes cannot be explained by either simple mixing of surface and subsurface inflow or by evaporative concentration. At Abert Lake, Oregon, the interstitial solute concentrations increased with depth to values as much as five times greater than the lake, except where springs indicate significant ground-water input. Where Na + , Cl, and CO 2 species constitute more than 90% of the solutes, Na + Cl − "> Na+Cl− ratios in the lake water are lower than in interstitial solutions of bottom cores and higher than in playa fluids. At the same time, Na + K + "> Na+K+ ratios are highest in the fluids of lake bottom muds and lowest in playa interstitials. In deeper playa profiles, interstitial Na + Cl − "> Na+Cl− tended to decrease with depth (5 ft. maximum). In the Abert Lake area, as in other parts of the western Great Basin, Na + Cl − "> Na+Cl− ratios are indicative of total CO 2 in solution and the effects of organic decay in surficial sediments. These ratios, coupled with data on silica and bulk density, show that higher P CO2 accompanying decay promotes silicate dissolution and hydrogen ion exchange, stripping alkalis from sediment which had preferentially adsorbed K + when entering the lake. On subsequent loss of pore fluid in the playa regime, silica initially released to solution in the lake environment is readsorbed on dissolution products.

Oregon↗

Hydrology of Crater, East and Davis Lakes, Oregon; with section on Chemistry of the Lakes

Crater, East, and Davis Lakes are small bodies of fresh water that occupy topographically closed basins in Holocene volcanic terrane. Because the annual water supply exceeds annual evaporation, water must be lost by seepage from each lake. The seepage rates vary widely both in volume and in percentage of the total water supply. Crater Lake loses about 89 cfs (cubic feet per second), equivalent to about 72 percent of its average annual supply. East Lake loses about 2.3 cfs, or about 44 percent of its estimated supply. Davis Lake seepage varies greatly with lake level, but the average loss is about 150 cfs, more than 90 percent of its total supply. The destination of the seepage loss is not definitely known for any of the lakes. An approximate water budget was computed for stationary level for each lake, by using estimates 'by the writer to supplement the hydrologic data available. The three lake waters are dilute. Crater Lake contains about 80 ppm, (parts per million) of dissolved solids---mostly silica, sodium, and bicarbonate, and lesser amounts of calcium, sulfate, and chloride. Much of the dissolved-solids content of Crater Lake---especially the sulfate and chloride---may be related to fumarole and thermal-spring activity that presumably followed the collapse of Mount Mazama. Although Grater Lake loses an estimated 7,000 tons of its 1.5million-ton salt content each year by leakage, the chemical character of the lake did not change appreciably between 1912 and 1964. East Lake contains 200 ppm of dissolved solids, which includes major proportions of calcium, sodium, bicarbonate, and sulfate, but almost no chloride. The lake apparently receives much of its dissolved solids from subsurface thermal springs. Annual solute loss from East Lake by leakage is about 450 tons, or 3 percent of the lake's 15,000-ton estimated solute content. Davis Lake contains only 48 ppm of dissolved solids, much of which is silica and bicarbonate; chloride is almost completely absent. Approximate physical and hydrologic data for the lakes are summarized in the following table. [Table]

Water Supply Paper↗

Ground-water resources of Island County with a section on quality of the ground water

The population of Island County has grown from 6,700 in 1940 to about 22,000 in 1964, causing a corresponding increase in the demand for water. Ground water is the only significant source of water within the county. Average annual precipitation ranges from less than 20 to more than 40 inches, and is the only recharge to the ground-water body.

Washington↗