Selected sources of information on United States and world energy resources--An annotated bibliography
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Attaining acceptable precision in extractable element determinations is more difficult than in total element determinations. In total element determinations, dissolution of the sample is qualitatively checked by the clarity of the solution and the absence of residues. These criteria cannot be used for extracts. Possibilities for error are introduced in virtually every step in soil extractions. Therefore, the use of reference materials whose homogeneity and element content are reasonably well known is essential for determination of extractable elements. In this report, estimates of homogeneity and element content are presented for four reference samples. Bulk samples of about 100 kilograms of each sample were ground to pass an 80-mesh sieve. The samples were homogenized and split using a Jones-type splitter. Fourteen splits of each reference sample were analyzed for total content of Ca, Co, Cu, Fe, K, Mg, Mn, Na, and Zn; DTPA-extractable Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn; exchangeable Ca, Mg, K, and Na; cation exchange capacity water-saturation-extractable Ca, Mg, K, Na, C1, and SO4; soil pH; and hot-water-extractable boron. Error measured between splits was small, indicating that the samples were homogenized adequately and that the laboratory procedure provided reproducible results.
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This Digital Data Series publication contains both raw and processed seismic data recorded during the period 1975 through 1978 by several geophysical service companies under contract to the USGS in the following study areas of the Powder River Basin, Montana and Wyoming: 1. Powder River and Custer Counties, MT (T. 1 S., T. 1-2 N., R. 53-54 E.) 2. Carter County, MT (T. 57-58 N., R. 65 W.) and Crook County, WY (T. 9 S., R.57-58 E.) 3. Powder River and Carter Counties, MT (T. 8 S., R. 53-55 E.) 4. Niobrara County, WY (T. 36-38 N., R. 61-62 W.) and Weston County, WY (T. 45 N., R. 61 W.) Four multichannel Vibroseis seismic lines, six Vertical Seismic Profiles (VSP's), and associated support material (observer's notes, X-Y coordinates, elevations of source and receivers, for example) are included. The raw (unprocessed) field data and a processed version of each surface profile and VSP are contained in standard SEG-Y format files; support material are in ASCII format text files. The processed surface data are versions which were reprocessed by the USGS in 1995 using state-of-the-art seismic data processing software.
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The Trout Lake Watershed is in the Northern Highlands Lake District in north-central Wisconsin. The study area includes four subbasins with five lakes and two bog lakes. The objectives of the Trout Lake WEBB project are to (1) describe processes controlling water and solute fluxes in the Trout Lake watershed, (2) examine interactions among those processes and (3) improve the capability to predict changes in water and solute fluxes for a range of spatial and temporal scales (Elder and others, 1992).
The Panola Mountain Research Watershed (PMRW) is a 41-hectare forested watershed in the southern Piedmont physiographic province near Atlanta, Georgia. The watershed contains a naturally regenerated second-growth forest on abandoned agricultural land, typical of the Piedmont. Research at PMRW has focused on how streamflow is generated, and in particular, on how water and solutes move from hillslopes to the stream. The research shows that streamflow and solute concentrations of precipitation, throughfall, soil water and streamwater change rapidly during rainstorms. Furthermore, these variations are strongly associated with the soil-moisture conditions, the soil type and thickness, and the rainfall intensity, all of which effect the chemical interactions and mixing of water traveling along hydrological pathways over and through the bedrock and soils.
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