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Geological, geophysical, and seismic data are being assembled and organized into a knowledge base for Western China as part of the CTBT Research and Development regional characterization effort. We have begun our analysis using da...
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Geological, geophysical, and seismic data are being assembled and organized into a knowledge base for Western China as part of the CTBT Research and Development regional characterization effort. We have begun our analysis using data from the station WMQ of the Chinese Digital Seismic Network (CDSN). Regional seismograms are being analyzed to construct travel time curves, velocity models, attenuation characteristics, and to quantify regional propagation effects such as phase blockages. Using locations from the USGS Preliminary Determination of Epicenters (PDE), we have identified Pn, Pg, Sn, and Lg phases, constructed travel time curves, and estimated apparent velocities using linear regression. Surface wave group velocities will be measured and inverted for regional structure. Preliminary noise spectra for WMQ have been obtained from the IRIS DMC. Chinese seismicity catalogs from the USGS and SSB are being used to identify and obtain seismic data (including mine seismicity) and information for lower magnitude events. We have identified the locations of nearly 500 mines in China for inclusion in the knowledge base.
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A unique data-base design has been devised to handle massive quantities of gridded geophysical data and to support a variety of marine geologic applications. The structure of the data base allows for storage of mean grid-point val...
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A unique data-base design has been devised to handle massive quantities of gridded geophysical data and to support a variety of marine geologic applications. The structure of the data base allows for storage of mean grid-point values with covariables (number of observations, maximum, minimum, and standard deviation). The Geographic Review and Cursor Editing (GRACE) program has been written for data-base manipulation. A limited fine mesh option in the data base permits increased resolution in special study areas. The data-base design has been applied to marine bathymetric, magnetic, and gravity data. (ERA citation 10:005590)
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The thesis consists of seven chapters and five appendices. Chapter one describes the nature of airborne geophysical surveys and subsequent problems in square grid data preparation that may be solved by introducing the Radon transf...
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The thesis consists of seven chapters and five appendices. Chapter one describes the nature of airborne geophysical surveys and subsequent problems in square grid data preparation that may be solved by introducing the Radon transform to potential field data treatment. Chapter 2 focusses on the definition and computation of the Radon transform. In Chapter 3, the Radon transform gridding method (RTGM) is developed for treatment of airborne geophysical data gridding. Chapter 4 discusses the possibility of performing directional filtering in the Radon transform domain (RTDF). The emphasis in Chapter 5 is put on the development of potential field continuation and derivatives in the Radon transform domain (RTCM and RTVD). In Chapter 6, one practical aeromagnetic data set from the Republic of Botswana is used to demonstrate on real data the methods developed in the previous chapters. In chapter 7, conclusions are drawn from previous discussions and practical data applications.
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Approximately 14,800 acres of the Orejana Canyon Wilderness Study Area was evaluated for identified mineral resources (known) and mineral resource potential (undiscovered). The study area is located in south-central Oregon, 35 mi ...
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Approximately 14,800 acres of the Orejana Canyon Wilderness Study Area was evaluated for identified mineral resources (known) and mineral resource potential (undiscovered). The study area is located in south-central Oregon, 35 mi north of Plush, Oreg. Geologic studies, geochemical sampling, and an inventory of mines and prospects indicate low resource potential for gold and silver along the west boundary of the study area and low resource potential for tin in the northwestern part of the study area. The entire study area has low potential for oil and gas resources. There is no geothermal energy or energy mineral resource potential in the study area. The study area contains no identified resources.
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This glossary was produced primarily for use by all Bureau of Land Management personnel and is of particular value to newly hired cadastral and cartographic personnel. Private, county, state and government agency surveyors and car...
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This glossary was produced primarily for use by all Bureau of Land Management personnel and is of particular value to newly hired cadastral and cartographic personnel. Private, county, state and government agency surveyors and cartographers will also find it a valuable publication. The definitions are not intended to conflict with those in other glossaries; however, this glossary is for Bureau of Land Management personnel and some terms will have a meaning unique to the Bureau.
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High-resolution and reconnaissance data, acquired using sensors mounted on a helicopter, were used to characterize waste sites and detect geologic properties that influence contaminant transport on the Oak Ridge Reservation (ORR),...
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High-resolution and reconnaissance data, acquired using sensors mounted on a helicopter, were used to characterize waste sites and detect geologic properties that influence contaminant transport on the Oak Ridge Reservation (ORR), Tennessee, between December 1992 and April 1994. To date, these data have been used to support several ORR Environmental Restoration (ER) programs. This report summarizes the techniques used, the ways in which the data have been applied to date, and current plans for enhancing the data and making them more useful to the ER programs.
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High-resolution and reconnaissance data, acquired using sensors mounted on a helicopter, were used to characterize waste sites and detect geologic properties that influence contaminant transport on the Oak Ridge Reservation (ORR),...
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High-resolution and reconnaissance data, acquired using sensors mounted on a helicopter, were used to characterize waste sites and detect geologic properties that influence contaminant transport on the Oak Ridge Reservation (ORR), Tennessee, between December 1992 and April 1994. To date, these data have been used to support several ORR Environmental Restoration (ER) programs. This report summarizes the techniques used, the ways in which the data have been applied to date, and current plans for enhancing the data and making them more useful to the ER programs.
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Approximately 85,470 acres of the Diablo Canyon Wilderness Study Area was evaluated for identified mineral resources (known) and mineral resource potential (undiscovered). Fieldwork was conducted in 1986, 1988, and 1989 to assess ...
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Approximately 85,470 acres of the Diablo Canyon Wilderness Study Area was evaluated for identified mineral resources (known) and mineral resource potential (undiscovered). Fieldwork was conducted in 1986, 1988, and 1989 to assess the mineral resources and resource potential of the study area. No energy or mineral resources were identified in the study area, but brines within lake and playa sediments contain concentrations of chemical components suitable for the production of soda ash, boron compounds, and sodium sulfate. Possible byproducts include potash, salts, bromine, lithium, magnesium compounds, and tungsten. Limestone from the study area could be used in the recovery process of brine components. The study area includes thermal springs and lies within 2 mi of the Summer Lake Known Geothermal Resource Area (KGRA). The resource potential of the entire study area is moderate for low-temperature geothermal energy useful for agricultural and building heating and is low for oil and gas.
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This technical note documents a survey of existing geophysical equipment and techniques for dredging use. Information presented provides planners and operators guidance in selecting appropriate equipment and geophysical techniques...
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This technical note documents a survey of existing geophysical equipment and techniques for dredging use. Information presented provides planners and operators guidance in selecting appropriate equipment and geophysical techniques applicable to specific project objectives.
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