Karl J Ellefsen
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Science and Products
Distribution of Fibrous Erionite in the United States and Implications For Human Health
Fibrous erionite, a zeolite mineral, has been designated as a human carcinogen by the World Health Organization and is believed to be the cause of extraordinarily high rates of malignant mesothelioma and other asbestos - related diseases in several villages in Central Turkey. A recent study by the University of Hawaii in collaboration with the U. S. Environmental Protection Agency in Dunn...
Data for generating statistical maps of soil cobalt concentrations in the conterminous United States
The product data are six statistics that were estimated for the chemical concentration of cobalt in the soil C horizon of the conterminous United States (Smith and others, 2013). The estimates are made at 9998 locations that are uniformly distributed across the conterminous United States. The six statistics are the mean for the isometric log-ratio transform of the concentrations, the equi
Selected Data from Preliminary Report on the Timmins-Kirkland Lake Area Gold Deposits File
Data on gold deposits are extracted from an existing publication to enable analysis. The data comprise selected portions of a data set that are published by C.J. Hodgson in "Preliminary Report on the Timmins-Kirkland Lake Area Gold Deposits File," which is available online as a digital image of a report. As an image, the data set cannot be analyzed. Consequently, selected portions of th
Titanium concentrations in stream sediments from the Atlantic Coastal Plain of the southeastern U.S. (1975-1999)
The titanium concentrations were obtained from a data set that is called the "National Geochemical Survey." This data set, as well as its documentation, are available in U.S. Geological Survey Open-File Report 2004-1001 (https://mrdata.usgs.gov/geochem/doc/home.htm). The titanium concentrations were measured in 3,457 samples of stream...
Evaluation of the analytical methods used to determine the elemental concentrations found in the stream geochemical dataset compiled for Alaska
A recent U.S. Geological Survey data compilation of stream-sediment geochemistry for Alaska contains decades of analyses collected under numerous Federal and State programs. The compiled data were determined by various analytical methods. Some samples were reanalyzed by a different analytical method than the original, resulting in some elements...
Wang, Bronwen; Ellefsen, Karl J.; Granitto, Matthew; Kelley, Karen D.; Karl, Susan M.; Case, George N.D.; Kreiner, Douglas; Amundson, Courtney L.
Bayesian modeling of non-stationary, univariate, spatial data for the Earth sciences
Some Earth science data, such as geochemical measurements of element concentrations, are non-stationary—the mean and the standard deviation vary spatially. It is important to estimate the spatial variations in both statistics because such information is indicative of geological and other Earth processes. To this end, an estimation method is...
Ellefsen, Karl J.; Van Gosen, Bradley S.
User guide to the bayesian modeling of non-stationary, univariate, spatial data using R language package BMNUS
Bayesian modeling of non-stationary, univariate, spatial data is performed using the R-language package BMNUS. A unique advantage of this package is that it can map the mean, standard deviation, quantiles, and probability of exceeding a specified value. The package includes several R-language classes that prepare the data for the modeling, help...
Ellefsen, Karl J.; Goldman, Margaret A.; Van Gosen, Bradley S.
Geochemical and mineralogical maps, with interpretation, for soils of the conterminous United States
Between 2007 and 2013, the U.S. Geological Survey conducted a low-density (1 site per 1,600 square kilometers, 4,857 sites) geochemical and mineralogical survey of soils in the conterminous United States. The sampling protocol for the national-scale survey included, at each site, a sample from a depth of 0 to 5 centimeters, a composite of the soil...
Smith, David B.; Solano, Federico; Woodruff, Laurel G.; Cannon, William F.; Ellefsen, Karl J.
Effect of size-biased sampling on resource predictions from the three-part method for quantitative mineral resource assessment—A case study of the gold mines in the Timmins-Kirkland Lake area of the Abitibi greenstone belt, Canada:
The three-part method for quantitative mineral resource assessment is used by the U.S. Geological Survey to predict, within a specified assessment area, the number of undiscovered mineral deposits and the quantity of mineral resources in those undiscovered deposits. The effects of size-biased sampling on such predictions are evaluated in a case...
Ellefsen, Karl J.
Shear-wave seismic reflection studies of unconsolidated sediments in the near surface
We have successfully applied of SH-wave seismic reflection methods to two different near-surface problems targeting unconsolidated sediments. At the former Fort Ord, where the water table is approximately 30m deep, we imaged aeolian and marine aquifer and aquitard stratigraphy to a depth of approximately 80m. We identified reflections from sand/...
Ellefsen, Karl J.; Haines, Seth S.
Titanium mineral resources in heavy-mineral sands in the Atlantic coastal plain of the southeastern United States
This study examined titanium distribution in the Atlantic Coastal Plain of the southeastern United States; the titanium is found in heavy-mineral sands that include the minerals ilmenite (Fe2+TiO3), rutile (TiO2), or leucoxene (an alteration product of ilmenite). Deposits of heavy-mineral sands in ancient and modern coastal plains are a...
Van Gosen, Bradley S.; Ellefsen, Karl J. Rare earth mineral potential in the southeastern U.S. Coastal Plain from integrated geophysical, geochemical, and geological approaches
We combined geophysical, geochemical, mineralogical, and geological data to evaluate the regional presence of rare earth element (REE)−bearing minerals in heavy mineral sand deposits of the southeastern U.S. Coastal Plain. We also analyzed regional differences in these data to determine probable sedimentary provenance. Analyses of heavy mineral...
Shah, Anjana K.; Bern, Carleton R.; Van Gosen, Bradley S.; Daniels, David L.; Benzel, William M.; Budahn, James R.; Ellefsen, Karl J.; Karst, Adam; Davis, Richard
Probability calculations for three-part mineral resource assessments
Three-part mineral resource assessment is a methodology for predicting, in a specified geographic region, both the number of undiscovered mineral deposits and the amount of mineral resources in those deposits. These predictions are based on probability calculations that are performed with computer software that is newly implemented. Compared to...
Ellefsen, Karl J.
User’s guide for MapMark4—An R package for the probability calculations in three-part mineral resource assessments
MapMark4 is a software package that implements the probability calculations in three-part mineral resource assessments. Functions within the software package are written in the R statistical programming language. These functions, their documentation, and a copy of this user’s guide are bundled together in R’s unit of shareable code, which is...
Ellefsen, Karl J. Titanium concentrations in stream sediments from the Atlantic Coastal Plain of the southeastern U.S. (1975-1999)
The titanium concentrations were obtained from a data set that is called the "National Geochemical Survey." This data set, as well as its documentation, are available in U.S. Geological Survey Open-File Report 2004-1001 (https://mrdata.usgs.gov/geochem/doc/home.htm). The titanium concentrations were measured in 3,457 samples of stream sediments...
Ellefsen, Karl J. Undiscovered porphyry copper resources in the Urals—A probabilistic mineral resource assessment
A probabilistic mineral resource assessment of metal resources in undiscovered porphyry copper deposits of the Ural Mountains in Russia and Kazakhstan was done using a quantitative form of mineral resource assessment. Permissive tracts were delineated on the basis of mapped and inferred subsurface distributions of igneous rocks assigned to...
Hammarstrom, Jane M.; Mihalasky, Mark J.; Ludington, Stephen; Phillips, Jeffrey; Berger, Byron R.; Denning, Paul; Dicken, Connie; Mars, John C.; Zientek, Michael L.; Herrington, Richard J.; Seltmann, Reimar