Geology Reports⌕ Search

Geology topics

R. C. Severson

Publications and source records attributed to R. C. Severson.

At least 55 records · Page 3Linked to original sources
USGS1986

Geochemical variability of soils and biogeochemical variability of plants in the Piceance Basin, Colorado

Geochemical baselines for native soils and biogeochemical baselines for plants in the Piceance basin provide data that can be used to assess geochemical and biogeochemical effects of oil-shale development, monitor changes in the geochemical and biogeochemical environment during development, and assess the degree of success of rehabilitation of native materials after development. Baseline values for 52 properties in native soils, 15 properties in big sagebrush, and 13 properties in western wheatgrass were established. Our Study revealed statistically significant regional variations of the following properties across the basin: in soil&-aluminum, cobalt, copper, iron, manganese, sodium, nickel, phosphorus, lead, scandium, titanium, vanadium, zinc, organic and total carbon, pH, clay, dolomite, sodium feldspar, and DTPA-extractable calcium, cadmium, iron, potassium, manganese, nickel, phosphorus, yttrium, and zinc; in big sagebrush-barium, calcium, copper, magnesium, molybdenum, sodium, strontium, zinc, and ash; and in western wheatgrass-boron, barium, calcium, magnesium, manganese, molybdenum, strontium, zinc, and ash. These variations show up as north-south trends across the basin, or they reflect differences in elevation, hydrology, and soil parent material. Baseline values for properties that do not have statistically significant regional variations can be represented by geometric means and deviations calculated from all values within the basin. Chemical and mineralogical analyses of soil and chemical analyses of western wheatgrass samples from Colorado State University's experimental revegetation plot at Anvil Points provide data useful in assessing potential effects on soil and plant properties when largescale revegetation operations begin. The concentrations of certain properties are related to the presence of topsoil over spent shale in the lysimeters. In soils, calcium, fluorine, lithium, magnesium, sodium, phosphorus, strontium, carbonate and total carbon, and DTPA-extractable boron, copper, iron, magnesium, and nickel have lower concentrations in topsoil than in the spent oil shale; whereas, silicon, titanium, ytterbium, clay, quartz, and DTPA-extractable potassium have greater concentrations in the topsoil than in the spent oil shale. In western wheatgrass, molybdenum has a lower concentration in grasses growing on the topsoil than in grasses on the spent oil shale; whereas, barium, calcium, manganese, strontium, zinc, and ash have greater concentrations in grasses growing on the topsoil than on the spent oil shale. When compared to baseline values, soils in the revegetation plot are significantly higher in concentrations of lead, zinc, organic and total carbon, and DTP A-extractable cadmium, iron, manganese, nickel, phosphorus, and zinc. Whereas, western wheatgrass grown within the revegetation plot has concentrations which fall within the baseline values established in the regional study. The equations used in predicting concentrations of elements in plants from native and altered sites are cumbersome because of the large number of variables required to adequately predict expected concentrations and are of limited use because many explained only a small proportion of the total variation.

Professional Paper↗
USGS1985

The occurrence of extractable elements in soils from the northern Great Plains

The modes of occurrence of extractable elements from 21 A and C horizon samples of uncultivated soils were examined using R-mode factor analysis. The extractants (DTPA, EDTA, HCl, hydroquinone, magnesium nitrate, and ammonium oxalate) cover a wide range of chemical attack. Four major elements (Ca, K, Mg, and Na) and eight trace elements (Cd, Co, Cu, Fe, Mn, Ni, Pb, and Zn) were determined in each extractant solution. A variety of chemical, mineralogical, and physical variables were also determined on each sample. Four varimax factors (clay, organic, Fe and Mn oxides, and soluble-Na) accounted for 74.2% of the total variance of the 90 variables for the A horizon. Seven varimax factors (Fe and Mn oxides, clay, CEC, soluble-Na, organic, Fe and Mn, and plagioclase) accounted for 77.2% of the total variance of the 79 variables for the C horizon. A and C horizon extractable trace elements are most generally related to Fe and Mn oxides, as indicated by loadings on the Fe and Mn oxide factor for both the A and C horizons. Each extractant generally operates on different modes of occurrence of an element in soil. For example, substantial differences occur between the HCl-, oxalate-, and hydroquinone-extractable trace elements. However, the modes of occurrence for trace elements removed by DTPA and EDTA were very similar, suggesting strong relationships between elements dissolved by these two extractants. The modes of occurrence for each individual major element are similar with each of the six extractants. A horizon Ca and Mg, and C horizon K and Mg are strongly related to a clay factor. C horizon Ca and A horizon K are strongly related to the CEC and organic factors, respectively. Both A and C horizon extractable Na are very strongly related to the soluble-Na factor. These results suggest that extractable major elements are water-soluble and are associated with the constituents that are responsible for that factor. Consequently, strong relationships should occur for any individual major element dissolved by any pair of extractants.

northern Great Plains↗
USGS1984

Chemical analyses of soils and other surficial materials, Alaska

Introduction: The favorable response to the reports on the geochemistry of unconsolidated surficial materials of the conterminous United States (informally called the '50-mile geochemical survey,' Shacklette and others, 1971a, 1971b, 1973, and 1974) led us, in 1975, to initiate a somewhat similar survey of Alaska. The principal objective of studies of this type is to establish estimates of the abundance of elements in soils and other surficial materials. Such information is useful in the evaluation of geochemical data for (1) mineral resources, (2) environmental appraisals, and (3) the definition of broad-scale geochemical patterns. For about six years this effort progressed slowly on a non-funded, time-available basis. During fiscal years 1982 and 1983, however, some funds were made available through the USGS Energy Lands and Alaska Mineral Surveys programs which allowed for the completion of the field-work phase of the project. The sampling plan was kept simple because, as with the 50-mile study, the acquisition of samples depended on the voluntary cooperation of field personnel (only about 40 percent of the total number of samples was obtained by the authors).

Open-File Report↗
USGS1984

Rehabilitation materials from surface- coal mines in western U.S.A. III. Relations between elements in mine soil and uptake by plants.

Plant uptake of Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn from mine soils was assessed using alfalfa Medicago sativa, sainfoin Onobrychis viciaefolia, smooth brome Bromus inermis, crested wheatgrass Agropyron cristatum, slender wheatgrass A. trachycaulum and intermediate wheatgrass A. intermedium; mine soil (cover-soil and spoil material) samples were collected from rehabilitated areas of 11 western US surface-coal mines in North Dakota, Montana, Wyoming and Colorado. Correlations between metals in plants and DTPA-extractable metals from mine soils were generally not statistically significant and showed no consistent patterns for a single metal or for a single plant species. Metal uptake by plants, relative to amounts in DTPA extracts of mine soil, was positively related to mine soil organic matter content or negatively related to mine soil pH. DTPA-extractable metal levels were significantly correlated with mine soil pH and organic-matter content.-from Authors

Reclamation and Revegetation Research↗
USGS1983

Rehabilitation materials from surface- coal mines in western USA. I. Chemical characteristics of spoil and replaced cover-soil.

A range of at least one order of magnitude was observed for DTPA-extractable Cd, Cu, Fe, Mn, Ni, Pb and Zn and organic matter content of samples of spoil and cover-soil from eleven western USA surface-coal mines. The observed pH of these samples ranged from 3.9 to 8.9; however, most samples were near-neutral to alkaline in reaction. Most constituent levels were found to be below proposed guidelines for maximum permissible levels in mine soil. -from Authors

Reclamation and Revegetation Research↗
USGS1981

Geochemical variability of natural soils and reclaimed mine-spoil soils in the San Juan Basin, New Mexico

An inventory of total-and extractable-element concentrations in soils was made for three areas of the San Juan Basin in New Mexico: (1) the broad area likely to be affected by energy-related development. (2) an area of soils considered to have potential for use as topsoil in mined-land reclamation. and (3) an area of the San Juan coal mine that has been regraded. topsoiled, and revegetated. Maps made of concentrations of 16 elements in area 1 soils show no gradational pattern across the region. Further. these maps do not correspond to those showing geology or soil types. Sodic or saline problems, and a possible but unproven deficiency of zinc available to plants. may make some of the soils in this area undesirable for use as topsoil in mined-land reclamation. Taxonomic great groups of soil in this area cannot be distinguished because each great group tends to have a large within-group variability if compared to the between-group variability. In area 2 the major soils sampled were of the Sheppard. Shiprock. and Doak association. These soils are quite uniform in chemical composition and are not greatly saline or sodic. As in area 1 soils. zinc deficiency may cause a problem in revegetating most of these soils. It is difficult to distinguish soil taxonomic families by using their respective chemical compositions. because of small between-family variability. Topsoil from a reclaimed area of the San Juan mine (area 3) most closely resembles the chemical composition of natural C horizons of soil from area 1. Spoil material that has not been topsoiled is likely to cause sodic-and saline-related problems in revegetation and may cause boron toxicity in plants. Topsoiling has apparently ameliorated these potential problems for plant growth on mine spoil. Total and extractable concentrations for elements and other parameters for each area of the San Juan Basin provide background information for the evaluation of the chemical quality of soils in each area.

New Mexico↗
USGS1981

Biogeochemical variability of plants at native and altered sites, San Juan Basin, New Mexico

The San Juan Basin is becoming a major energy resource region. The anticipated increase in strip mining for coal can be expected to alter the geochemical and biogeochemical environment. because such activities destroy the native vegetation communities, rearrange the rock strata, and disrupt natural soil development. This study investigated the variability in the biogeochemistry of native plant species at both undisturbed and altered sites and assessed the importance of the observed differences. Three studies are involved in this investigation: Study 1, the biogeochemical variability of native species found at sites throughout that part of the basin underlain by economically recoverable coal; Study 2, the biogeochemical variability of native species growing on soils considered favorable for use in the topsoiling of spoil areas; and Study 3, the biogeochemical variability of native species on rehabilitated sites at the San Juan coal mine. Summary statistics for concentrations of 35 elements (and ash yield) are reported in Study 1 for galleta grass, broom snakeweed, and fourwing saltbush. The concentrations of manganese, molybdenum, nickel, and uranium (and possibly iron and selenium) in galleta show regional patterns, with the highest values generally found in the south-central region and western edge of the study area. Differences in the concentration of elements between species was generally subtle (less than a factor of two) except for the following: ash yield of saltbush was two times that of the other plants; boron in snakeweed and saltbush was four times greater than in galleta; iron in galleta was two times greater than in saltbush; and, calcium, magnesium, potassium, phosphorus, and sulfur were generally highest in saltbush. Summary statistics (including the 95-percent expected range) for concentrations of 35 elements (and ash yield) are reported from Study 2 for galleta and broom snakeweed growing on the Sheppard, Shiprock, and Doak soil association. Significant regional (greater than 10 km) variation for aluminum, iron, sulfur, vanadium, and zirconium in galleta are reported; however, for most elements, a significant proportion of the variation in the data was measured locally (less than 0.1 km). This variation indicates that samples of galleta and snakeweed taken more than 10 km apart vary, in their element composition, little more than plants sampled as close together as 0.1 km. The concentrations of 35 elements (and ash yield) in alkali sacaton and fourwing saltbush, which were collected on a rehabilitation plot at the San Juan mine (Study 3), are compared with those of control samples of similar material from native sites from throughout the ,an Juan Basin. Concentrations of aluminum, arsenic, boron, cobalt, copper, fluorine, iron, lead, manganese, sodium, and uranium in samples of saltbush growing over spoil generally exceed the levels of these elements in control samples. For many elements, concentrations in mine samples are from two to five times higher 1 han concentrations in the control samples. Sodium concentrations i saltbush, however, were 100 times higher in mine samples than in control samples. This high concentration reflects a corresponding : OO-fold increase in the extractable sodium levels in spoil material s compared to C-horizon control samples. Sampled plants from the l1ine area, spaced relatively close together (5 m (meters) or less), vary greatly in their element compositions, apparently in response 1 J the heterogenous composition and element availability of the l1ine soils. Topsoiling to a depth of 20 cm (centimeters) does little to meliorate the uptake of elements from spoil by saltbush.

Professional Paper↗
USGS1980

Four reference soil and rock samples for measuring element availability in the Western Energy Regions

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.

Circular↗
USGS1979

Environmental implications of element emissions from phosphate-processing operations in southeastern Idaho

In order to assess the contribution to plants and soils of certain elements emitted by phosphate processing, we sampled sagebrush, grasses, and A- and C-horizon soils along upwind and downwind transects at Pocatello and Soda Springs, Idaho. Analyses for 70 elements in plants showed that, statistically, the concentration of 7 environmentally important elements, cadmium, chromium, fluorine, selenium, uranium, vanadium, and zinc, were related to emissions from phosphate-processing operations. Two additional elements, lithium and nickel, show probable relationships. The literature on the effects of these elements on plant and animal health is briefly surveyed. Relations between element content in plants and distance from the phosphate-processing operations were stronger at Soda Springs than at Pocatello and, in general, stronger in sagebrush than in the grasses. Analyses for 58 elements in soils showed that, statistically, beryllium, fluorine, iron, lead, lithium, potassium, rubidium, thorium, and zinc were related to emissions only at Pocatello and only in the A horizon. Moreover, six additional elements, copper, mercury, nickel, titanium, uranium, and vanadium, probably are similarly related along the same transect. The approximate amounts of elements added to the soils by the emissions are estimated. In C-horizon soils, no statistically significant relations were observed between element concentrations and distance from the processing sites. At Soda Springs, the nonuniformity of soils at the sampling locations may have obscured the relationship between soil-element content and emissions from phosphate processing.

Professional Paper↗