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Geology of the Chitina Valley and Adjacent Area, Alaska

Description: From abstract: The Chitina Valley and adjoining area form part of a rugged alpine region in the southeast corner of the main body of Alaska and include a portion of the Chugach Mountains and most of the southern half of the Wrangell Mountains, to the north. The Chitina River is an eastern branch of the Copper River and rises in ice fields and valley glaciers occupying most of the country near the international boundary north of Mount St. Elias. The adjoining area described in this report includes the Hanagita and Bremner River district and the westward continuation of the north side of the Chugach Mountains as far as Valdez Arm and Klutina Lake. In addition, the geology of the upper White River district is described because of its relation to that of the Chitina Valley.
Date: 1938
Creator: Moffit, Fred H.
Item Type: Report

Geology and Fuel Resources of the Southern Part of the Oklahoma Coal Field: Part 3. Quinton-Scipio District

Description: From abstract: The Quinton-Scipio district includes about 450 square miles, mostly in Pittsburg County but partly in Haskell and Latimer Counties, Okla. The stratified rocks exposed at the surface in the district are the McAlester, Savanna, Boggy, Thurman, Stuart, and Senora formations, of Pennsylvanian age, and consist of alternating beds of shale and sandstone with some coal beds and a few beds of limestone less than 1 foot thick. The total thickness of these formations exposed in the district is between 3,000 and 3,300 feet. There are probably unconformities at the base of the Savanna sandstone and at the base of the Thurman sandstone. Overlying the Pennsylvanian formations in parts of the district are unconsolidated sand, gravel, and clay, which in part belong to the Gerty sand, a deposit in an abandoned Quaternary (?) river channel. Other unconsolidated deposits include sand on stream terraces and Recent alluvium.
Date: 1938
Creator: Dane, C. H.; Rothrock, Howard Eugene & Williams, James Steele
Item Type: Report

Chromite Deposits in Central Part Stillwater Complex, Sweet Grass County, Montana

Description: From abstract: The chromite deposits of the central part of the Stillwater complex lie in a belt 9 miles long between the valleys of Boulder River and the West Fork of the Stillwater River in Sweet Grass County, Mont. The chromite occurs as layers near the middle part of the ultramafic zone in the lower part of the complex. The layers, originally horizontal, have been tilted so that they dip northeastwards at angles ranging from nearly horizontal to nearly vertical, and are cut by many cross faults, the largest with a horizontal offset of 3,000 feet. Investigations by the United States Geological Survey and the United States Bureau of Mines have shown that in this belt there are 5 sections ranging in length from 850 to 3,800 feet along the strike where the continuity and grade of the chromite can be reasonably inferred.
Date: 1955
Creator: Howland, A. L.
Item Type: Report

Geology of the Mount Katmai Area, Alaska

Description: From abstract: The Mount Katmai area is on the Alaska Peninsula and comprises the Mount Katmai quadrangle, the Cape Douglas area of the adjoining Afognak quadrangle, and parts of the Karluk and Naknek quadrangles. The area, which includes nearly all the Katmai National Monument, is one of high relief and is drained by streams of preglacial origin. At least two ice advances are indicated by the moraine configuration. Present-day glaciation is restricted to numerous alpine glaciers in the mountain areas. Fifteen recently active volcanoes roughly form a line from Mount Douglas to Martin Mountain.
Date: 1959
Creator: Keller, A. Samuel & Reiser, Hillard N.
Item Type: Report

Mineral Resources of the San Carlos Indian Reservation, Arizona

Description: From abstract: At the request of the Council of the San Carlos Apache Tribe the U. S. Geological Survey entered into a cooperative agreement calling for a brief reconnaissance study to determine, as far as practical, the mineral potential of the San Carlos Indian Reservation. Five months of field work was done during the winter and spring of 1952-53. About 30 percent of the reservation is covered by alluvial deposits of late Tertiary, Pleistocene, and Recent age, and another 60 percent is covered by volcanic rocks of Tertiary and perhaps Pleistocene age. These rocks are younger than the major epochs of metallization in southeastern Arizona. The remainder of the area is underlain by pre-Cambrian and Paleozoic sedimentary rocks, pre-Cambrian granite, and pre-Devonian diabase.
Date: 1956
Creator: Bromfield, Calvin Stanton & Shride, Andrew F.
Item Type: Report

Geology and Coal Resources of the Salyersville North Quadrangle, Magoffin, Morgan, and Johnson Counties, Kentucky

Description: From introduction: The U.S. Geological Survey has conducted investigations of the geology and coal resources of the area in and adjacent to the Salyers-ville North quadrangle in the Eastern Kentucky coal field (fig. 7). The Salyersville North quadrangle lies between lat. 3745' and 37052'30'' N., and long. 8300' and 83 07'30'' E.; it is a 71/2-minute quadrangle in the southeast quarter of the Dingus 15-minute area which also includes the Dingus, Lenox, and White Oak 7 -minute quadrangles (fig. 8). The present report is the second for the 15-minute Dingus area; a report by Adkison (1957) has been published for the White Oak quadrangle and a third report is in preparation for the Lenox quadrangle. Other published reports for quadrangles in the vicinity are those by Englund (1955) for Cannel City to the west; Bergin (1962) for Seitz to the southwest; and Hauser (1953) for Paintsville to the east.
Date: 1963
Creator: Adkison, W. L. & Johnston, J. E.
Item Type: Report

Mineral Resources of the Blacktail Mountains Wilderness Study Area, Beaverhead County, Montana

Description: From summary:A mineral resource survey of a 10,610-acre part of the Blacktail Mountains Wilderness Study Area (MT-076- 002) was conducted in 1984-85. Identified subeconomic resources of barite exist in the area at the northernmost boundary, and a zone partly within the area along the northeastern boundary has a moderate mineral resource potential for silver and barite, and associated gold, copper, lead, and zinc. No producing mines occur in or adjacent to the area. The area lies within a region that is rated as having moderate energy resource potential for oil and for gas.
Date: 1987
Creator: Tysdal, Russell G.; Lee, Gregory K.; Hassemer, Jerry H.; Hanna, W. F. & Benham, J. R.
Item Type: Report

Electromagnetic-Acoustic-Transducer/Synthetic-Aperture System for Thick-Weld Inspection

Description: Abstract: This report describes a system based on electromagnetic-acoustic transducers (EMATs) as an approach to automated nondestructive evaluation of thick weldments (>25 mm). Good signal-to-noise ratios, often a problem with EMATs, were possibTe through careful design of the transducers and associated electronic circuits and the use of signal averaging. At 454 kHz, the transducers produce shear-horizontal waves of approximately 7-mm wavelength in steel. The long wavelength permits determination of through-thickness flaw depth from the amplitudes of scattered ultrasonic waves. A minicomputer controlled transducer positioning and acquired the digitized ultrasonic waveforms for synthetic aperture processing. The synthetic aperture technique further improved signal quality and yielded flaw localization through the weld thickness. Measurements on artificial flaws demonstrated a detectability threshold of 0.5 mm (through thickness) and sizing ability up to 2.5 mm, in agreement with theoretical predictions. Details include the design of the transducers and electronics, as well as the mechanical positioner, signal processing algorithms, and complete computer program listing.
Date: 1984
Creator: Fortunko, C. M.; Schramm, R. E.; Moulder, J. C. & McColskey, J. D.
Item Type: Report

Theory of Near-Field Phased Arrays for Electromagnetic Susceptibility Testing

Description: From introduction: The feasibility of using a near-field array for electromagnetic susceptibility testing is studied. The basic objective is to control the element weightings such that a plane wave is generated within the test volume. The basic theory is developed for arbitrary array geometries, and numerical results are obtained for finite planar arrays. A general near-field array synthesis technique is developed, and the technique minimizes the mean square error in the test volume while constraining the array excitations. The constraint prevents large excitations and is useful in minimizing the fields outside the test volume. The basic idea looks promising, but some practical considerations, such as bandwidth and angular scanning limitations, require further theoretical and experimental investigation.
Date: February 1984
Creator: Hill, D. A.
Item Type: Report

Small Aperture Analysis of the Dual TEM Cell and an Investigation of Test Object Scattering in a Single TEM Cell

Description: Introduction: Small aperture theory is used to investigate the dual TEM cell. Analyzing coupling through an empty versus a loaded aperture leads to a model of dual TEM cell shielding effectiveness measurements. Small obstacle scattering yields results for both the field perturbation and the change in a cell's transmission line characteristics due to the presence of a test object in a TEM cell. In each case, theoretical values are compared to experimental data.
Date: 1984
Creator: Wilson, Perry F. & Ma, Mark T.
Item Type: Report

Design and Error Analysis for the WR10 Thermal Noise Standard

Description: From introduction: This note describes the design and error analysis of a WR10 thermal noise power standard. The standard is designed to operate at the boiling point of liquid nitrogen with a noise temperature accurate to plus or minus 1 K.
Date: December 1983
Creator: Daywitt, William C.
Item Type: Report

A Coaxial Noise Standard for the 1 GHz to 12.4 GHz Frequency Range

Description: From introduction: This note describes the design and construction of a coaxial thermal noise standard. The standard is designed to operate at the boiling point of liquid nitrogen with a noise temperature accurate to t 1 K in the frequency range from 1 GHz to 12.4 GHz.
Date: 1984
Creator: Daywitt, William C.
Item Type: Report

An Error Analysis for the Use of Presently Available Lunar Radio Flux Data in Broadbeam Antenna-System Measurements

Description: From introduction: Simple, precise expressions for lunar diameter, average brightness temperature, flux density, and shape factor are presented. An analysis of the relationship between these parameters and corresponding errors are included. For broadbeam (HPBW>d) antennas, results show that flux density and shape factor can be determined with errors less than 13 percent and 0.4 percent respectively at frequencies below 10 GHz. Extension of the analysis to higher frequencies is indicated.
Date: February 1984
Creator: Daywitt, William C.
Item Type: Report

VOR Calibration Services

Description: from Introduction: The National Bureau of Standards has designed, constructed, and evaluated a standard for the support of very-high-frequency omnidirectional range (VOR) air navigation aids. The standard consists of two instruments: (1) a digital waveform signal generator for the composite VOR audio waveform, and (2) a standard phasemeter based on time series analysis of this waveform. Experimental results, a statistical analysis of them, and the principal software listings are included.
Date: April 1985
Creator: Larsen, Neil T.; Vecchia, Dominic F. & Sugar, George R.
Item Type: Report

Phase Equilibria: an Informal Symposium

Description: From introduction: The accurate prediction of phase equilibria plays an important. role in the chemical process industries. A grief overview of final phase equilibria predictive techniques is presented with special emphasis on methods in current use in industry. Areas were better fundamental understanding will lead to improved models are discussed whenever possible.
Date: January 1983
Creator: Eaton, B. E.; Ely, James F.; Hanley, H. J. M.; McCarty, Robert D. & Rainwater, James C.
Item Type: Report

A Review of Supercritical Fluid Extraction

Description: Forward: The purpose of this report is to summarize the results obtained from a brief investigation of supercritical fluid extraction principles and applications. This study was one portion of a project funded by the U.S. Department of Energy, Office of Fossil Energy, contract nuriber DE-AI01076PR06010, in response to a preliminary proposal submitted by the authors. This report sometimes uses company trade naries to identify processes and patent holders. This usage implies no endorsement by HBS. Note also that some figures reproduced from other sources do not conform with NBS policy concerning SI units.
Date: December 1983
Creator: Ely, James F. & Baker, Jolene K.
Item Type: Report

Reference Flat Pulse Generator

Description: Introduction: A reference step-like pulse generator is described which has been developed at NBS. This generator can be used for accurately characterizing the step response of various kinds of trap ient recording equipment (oscilloscopes, waveform recorders, transient digitizers, etc.). Basic design principles are given as well as complete circuit diagrams and descriptions. An analysis of the output stage of the generator is presented together with the circuit models for developing a time-domain computer simulation program using extended- SCEPTRE. Preliminary specifications indicate that the NBS Reference Flat Pulse Generator provides a negative-going reference transition duration (90 to 10 percent) of 600 ps, *20 percent with baseline perturbations of less than *2 percent for less than 5 ns.
Date: October 1983
Creator: Andrews, J. R.; Bell, B. A. & Baldwin, E. E.
Item Type: Report

The Characteristics of Iris-Fed Millimeterwave Rectangular Microstrip Patch Antennas

Description: From introduction: The fabrication of various iris-fed millimeterwave rectangular microstrip patch antennas is described. A model is proposed to describe the iris-fed antenna. Irises ranging in size from 15 percent of the area of the patch to the fully open waveguide are used to couple energy into the antenna. Resonance of the antenna is observed to be insensitive to the size of the iris for irises up to 115 percent of the size of the patch. A study is also made of th? relationship of coupling to the antenna as a function of position of the iris with respect to the transverse plane of the waveguide, the iris always being centered with respect to the patch. In general, the antenna has a VSWR in the waveguide feed on the order of 5:1 at resonance, except for the fully open waveguide which gives rise to a VSWR of 2.9:1 at resonance. Far-field antenna power patterns are observed to be quite broad with H-plane beamwidths on the order of 1300. Maximum antenna gain is seen to be 4.5 dBi with 3 dBi typical. An initial study is made of the microstrip patch antenna fed from a longitudinal waveguide wall. Results indicate that this feed structure is likely to prove valuable for microstrip patch antennas with coupling at least as good as for the transverse-fed patch added to the possibility of feeding of multiple patches from a single waveguide.
Date: October 1983
Creator: Greenlee, D. H.; Kanda, Motohisa & Chang, David C.
Item Type: Report

Optical Time-Domain Reflectometer Performance and Calibration Studies

Description: from Introduction: The measurement accuracy of the optical time-domain reflectometer (OTDR) is restricted in some applications by a limited operational dynamic range and by a lack of standardized test procedures. In an effort to better understand these restrictions, we have measured the range of linearity of some avalanche photodiodes used as backscatter detectors. Also, the effect of input launch conditions is examined and a possible standardized OTDR test procedure is proposed. Using these suggestions, we have made comparisons between attenuation values determined by cutback and backscatter methods and found that good agreement is possible. Finally, some methods are described for checking the response. linearity of OTDR systems.
Date: June 1983
Creator: Danielson, B. L.
Item Type: Report

Nonlinear Least Squares Regression Using STARPAC: The Standards Time Series and Regression Package

Description: From preface: This Note documents 16 subroutines for nonlinear least squares regression. Twelve of these compute the least squares estimates, performing either weighted or unweighted analysis with either numerically approximated or user-supplied (analytic) derivatives. The other four are user-callable subroutines for two procedures used within the estimation code: the first selects optimum step sizes for approximating the partial derivatives of the model; and the second checks the validity of a user-supplied derivative subroutine.
Date: October 1983
Creator: Donaldson, Janet R. & Tryon, Peter V.
Item Type: Report

Strippable lignite Deposits, Slope and Bowman Counties, North Dakota

Description: From abstract: Slope and Bowman Counties, N. Dak., include an area of about 2,450 square miles in the southeastern part of the Fort Union coal region of North Dakota, South Dakota, and Montana. In anticipation of a future increase in the demand for the low-rank coal of this region as a fuel for electric power plants and as a raw material for various chemical synthesizing processes, Slope and Bowman Counties were investigated for deposits of lignite that could be mined by large scale strip mining methods. All the lignite beds of economic importance in this area are in the Fort Union formation, particularly in the Tongue River member. The beds are nearly horizontal, dipping about 25 to 50 feet per mile north and northeast from the Cedar Creek anticline in the southwest corner of the area.
Date: 1955
Creator: Kepferle, Roy Clark & Culbertson, William C.
Item Type: Report