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D. E. Boleneus

Publications and source records attributed to D. E. Boleneus.

8 recordsLinked to original sources
USGS2002

Preliminary cellular-automata forecast of permit activity from 1998 to 2010, Idaho and Western Montana

For public land management in Idaho and western Montana, the U.S. Forest Service (USFS) has requested that the U.S. Geological Survey (USGS) predict where mineral-related activity will occur in the next decade. Cellular automata provide an approach to simulation of this human activity. Cellular automata (CA) are defined by an array of cells , which evolve by a simple transition rule, the automaton . Based on exploration trends, we assume that future exploration will focus in areas of past exploration. Spatial-temporal information about mineral-related activity, that is permits issued by USFS and Bureau of Land Management (BLM) in the last decade, and spatial information about undiscovered resources, provide a basis to calibrate a CA. The CA implemented is a modified annealed voting rule that simulates mineral-related activity with spatial and temporal resolution of 1 mi 2 and 1 year based on activity from 1989 to 1998. For this CA, the state of the economy and exploration technology is assumed constant for the next decade. The calibrated CA reproduces the 1989–1998-permit activity with an agreement of 94%, which increases to 98% within one year. Analysis of the confusion matrix and kappa correlation statistics indicates that the CA underestimates high activity and overestimates low activity. Spatially, the major differences between the actual and calculated activity are that the calculated activity occurs in a slightly larger number of small patches and is slightly more uneven than the actual activity. Using the calibrated CA in a Monte Carlo simulation projecting from 1998 to 2010, an estimate of the probability of mineral activity shows high levels of activity in Boise, Caribou, Elmore, Lincoln, and western Valley counties in Idaho and Beaverhead, Madison, and Stillwater counties in Montana, and generally low activity elsewhere.

Idaho, Montana↗
USGS2001

Assessment method for epithermal gold deposits in northeast Washington State using weights-of-evidence GIS modeling

The weights-of-evidence analysis, a quantitative mineral resource mapping tool, is used to delineate favorable areas for epithermal gold deposits and to predict future exploration activity of the mineral industry for similar deposits in a four-county area (222 x 277 km), including the Okanogan and Colville National Forests of northeastern Washington. Modeling is applied in six steps: (1) building a spatial digital database, (2) extracting predictive evidence for a particular deposit, based on an exploration model, (3) calculating relative weights for each predictive map, (4) combining the geologic evidence maps to predict the location of undiscovered mineral resources and (5) measuring the intensity of recent exploration activity by use of mining claims on federal lands, and (6) combining mineral resource and exploration activity into an assessment model of future mining activity. The analysis is accomplished on a personal computer using ArcView GIS platform with Spatial Analyst and Weights-of-Evidence software. In accord with the descriptive model for epithermal gold deposits, digital geologic evidential themes assembled include lithologic map units, thrust faults, normal faults, and igneous dikes. Similarly, geochemical evidential themes include placer gold deposits and gold and silver analyses from stream sediment (silt) samples from National Forest lands. Fifty mines, prospects, or occurrences of epithermal gold deposits, the training set, define the appropriate a really-associated terrane. The areal (or spatial) correlation of each evidential theme with the training set yield predictor theme maps for lithology, placer sites and normal faults. The weights-of-evidence analysis disqualified the thrust fault, dike, and gold and silver silt analyses evidential themes because they lacked spatial correlation with the training set. The decision to accept or reject evidential themes as predictors is assisted by considering probabilistic data consisting of weights and contrast values calculated for themes according to areal correlation with the training sites. Predictor themes having acceptable weights and contrast values are combined into a preliminary model to predict the locations of undiscovered epithermal gold deposits. This model facilitates ranking of tracts as non-permissive, permissive or favorable categories based on exclusionary, passive, and active criteria through evaluation of probabilistic data provided by interaction of predictor themes. The method is very similar to the visual inspection method of drawing conclusions from anomalies on a manually overlain system of maps. This method serves as a model for future mineral assessment procedures because of its objective nature. To develop a model to predict future exploration activity, the locations of lode mining claims were summarized for 1980, 1985, 1990, and 1996. Land parcels containing historic claims were identified either as those with mining claims present in 1980 or valid claims present in 1985. Current claim parcels were identified as those containing valid lode claims in either 1990 or 1996. A consistent parcel contains both historic and current claims. The epithermal gold and mining claim activity models were combined into an assessment (or mineral resource-activity) model to assist in land use decisions by providing a prediction of mineral exploration activity on federal land in the next decade. Ranks in the assessment model are: (1) no activity, (2) low activity, (3) low to moderate activity, (4) moderate activity and (5) high activity.

Washington↗
USGS2000

Geologic datasets for weights of evidence analysis in Northeast Washington: 4. mineral industry activity in Washington, 1985-1997

This report includes a table of 339 sites representing mineral activities for mining and mineral exploration in the State of Washington from 1985 through 1997. The table was primarily compiled from annual reports in Washington Geologic Newsletter and Washington Geology. The information was compiled for use in a weights-of-evidence analysis of mineral resources in northeastern Washington.

Washington↗
USGS2000

Geologic datasets for weights of evidence analysis in Northeast Washington: 4. mineral industry activity in Washington, 1985-1997

This report includes a table of 339 sites representing mineral activities for mining and mineral exploration in the State of Washington from 1985 through 1997. The table was primarily compiled from annual reports in Washington Geologic Newsletter and Washington Geology. The information was compiled for use in a weights-of-evidence analysis of mineral resources in northeastern Washington.

Washington↗
USGS1999

Digital analytical data from mineral resource assessments of national forest lands in Washington

Extensive reconnaissance assessments of the mineral resource potential of the Colville and Okanogan National Forests in northeastern Washington were conducted during 1979-1982 by a private consultant A.R. Grant, under contract with the U.S. Department of Agriculture, Forest Service. These forests occupy large parts of Pend Oreille, Stevens, Ferry, and Okanogan counties, and smaller parts of Whatcom, Skagit, and Chelan counties adjoining Okanogan County in the Cascades. Sampled terrain also included the Kaniksu National Forest in Pend Oreille County and one stream bed of the Kaniksu in adjacent Bonner County, Idaho. Two unpublished reports resulting from the assessments (Grant, 1982a,b) list a total of 3,927 analyses of gold, silver, copper, lead, zinc, molybdenum, tungsten, and uranium content of stream sediment and bedrock samples collected at widely dispersed sites in the three National Forests. This report makes this important body of work available in digital form on diskettes, to enhance manipulations with computer spreadsheets, geographic information systems (GIS), and digital spatial analyses. This will allow for utilization of data by modern day explorationists and by the general geodata user community.

Washington↗
USGS1999

Geologic datasets for weights-of-evidence analysis in northeast Washington: 2. Mineral databases

Digital mineral databases are necessary to carry out weights-of-evidence modeling of mineral resources for epithermal gold and carbonate-hosted lead-zinc deposits in northeast Washington. This report describes spreadsheet tables consisting of: 1) training sites for epithermal gold, 2) placer gold sites, 3) training sites for carbonate-hosted lead-zinc, and 4) small lead-zinc mines and prospects. A fifth table provides location data about sites in the four tables.

Washington↗