| Design and Fabrication Report |
30 SEP 1981 |
5 pages |
| Authors:
Robert C. Snare; CALIFORNIA UNIV LOS ANGELES INST OF GEOPHYSICS AND PLANETARY PHYSICS
|
 | The design and fabrication of fluxgate magnetometers and data systems is described. |
|
| A 'Worst Case' Spacecraft Environment as Observed by SCATHA on 24 April 1979 |
31 JUL 1981 |
|
| Authors:
E. G. Mullen; M. S. Gussenhoven; H. B. Garrett; AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA
|
 | A survey of data from the first year of the P78-2 SCATHA satellite operations showed that a highest level spacecraft frame charging (phi sub f) both in sunlight (-340 V) and in eclipse (> -8 kV) occurred on 24 April 1979. Analysis of the data indicates that if the sunlight charging environment had been present during eclipse, the vehicle would have charged in excess of 15 kV which is above ... |
|
| Narrowband Electromagnetic Emissions from Saturn's Magnetosphere |
21 MAY 1981 |
|
| Authors:
D. A. Gurnett; W. S. Kurth; F. L. Scarf; IOWA UNIV IOWA CITY DEPT OF PHYSICS AND ASTRONOMY
|
| During the Voyager 1 flyby of Saturn a series of narrowband electromagnetic emissions were detected by the plasma wave instrument coming from the inner region of the magnetosphere in the frequency range from 3 to 30 kHz. These emissions have many close similarities to continuum radiation detected in the Earth's magnetosphere and narrowband kilometric radiation (nKOM) detected in the Jovian magnetosphere. Based on the close similarity to the terrestrial continuum ... |
|
| Solar Wind Control of Auroral Zone Geomagnetic Activity |
01 MAY 1981 |
|
| Authors:
C. Robert Clauer; Robert L. McPherron; Craig Searls; Margaret G. Kivelson; STANFORD UNIV CA INST FOR PLASMA RESEARCH
|
|
| Data Report for Oceanographic/Geophysical Surveys in the Northwest Pacific (46-47 N, 159-161 E): USNS Silas Bent, 2-3 August 1980. |
MAR 1981 |
|
| Authors:
J. A. Green; S. D. Trowell; NAVAL OCEAN RESEARCH AND DEVELOPMENT ACTIVITY NSTL STATION MS
|
| This note presents the results of a geophysical/oceanographic survey of Area 2 selected from Green and Fleischer (1980). The surveyed area has an average depth of 5300 m and is located on the eastern flank of the Hokkaido Rise. Average unconsolidated sediment thickness is 0.45 seconds of two-way travel time (approximately 400 m). These sediments are probably siliceous clays interspersed with volcanic ash layers and their calculated acoustic interval velocity ... |
|
| Height-Gain Atlas for an Elemental Vertical Electric Dipole Above a Flat Earth, |
MAR 1981 |
|
| Authors:
John L. Heckscher; Eli J. Tichovolsky; ROME AIR DEVELOPMENT CENTER GRIFFISS AFB NY
|
| The complex height-gain for an infinitesimal vertical electric dipole (VED) above each of five homogeneous flat surfaces representative of sea water, well-conducting earth, poorly conducting earth, fresh water, and ice is calculated at 0.1, 1, 10, and 100 MHz for selected ranges. The amplitude and phase of the three cylindrical electromagnetic field components are given for source elevations of 0, 3/4, and 3/2 wavelengths in sets of 36 tables and ... |
|
| Advancements in Chinese Geomagnetism and Aeronomy during the Last Thirty Years, |
09 FEB 1981 |
|
| Authors:
Zhu Gangkun; FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OH
|
|
| Emission of Particles from a Charged Sphere into a Magnetic Field. Part II |
26 JAN 1981 |
|
| Authors:
Christopher Sherman; AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA
|
| Trajectories of particles emitted normally from a charged sphere into a constant magnetic field are examined. Corrections are made to previous calculations which led to the separation of such trajectories into two classes, those which return to the sphere and those which do not. (Author) |
|
| Changes of the Sq Quiet Daily Variations of the Geomagnetic Field as a Function of Time of Year and Latitude, |
1981 |
|
| Authors:
Wallace H. Campbell; GEOLOGICAL SURVEY DENVER COLO
|
| An analytic representation of the quiet daily variation of the geomagnetic field, Sq, was obtained for the North American region with a mean error of less than 10% of the daily variation range. The month by month 24-, 12-, 8-, and 6-hr Fourier components of the field in H, D, and Z were found to have significant annual and semiannual changes that, in general, agreed with the expectations for ionospheric ... |
|
| Field-Aligned Current, Convective Electric Field, and Auroral Particle Measurements during a Major Magnetic Storm |
1981 |
|
| Authors:
B. M. Shuman; R. P. Vancour; M. Smiddy; N. A. Saflekos; F. J. Rich; BOSTON COLL CHESTNUT HILL MA DEPT OF PHYSICS
|
|
| The Measurement of Earth Resistivity Affecting MHD-EMP (magnetohydrodynamic Electromagnetic Pulse) Response of Buried Cables |
01 DEC 1980 |
|
| Authors:
J. W. Erler; V. A. J. VAN Lint; MISSION RESEARCH CORP SAN DIEGO CA
|
| The response of buried conducting cable to a MHD EMP wave is determined in part by the resistivity of the earth at frequencies ranging from 10 to 0.01 Hz. Three methods of measurement of earth resistivity are presented with their advantages and limitations. (Author) |
|
| Characteristics of Geomagnetic Power Spectra on Land and Sea in the Period Range 0.2 to 400 Seconds. |
DEC 1980 |
|
| Authors:
Gary M. McKinley; Robert M. Santos; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Geomagnetic field fluctuations in the 0.025-5Hz range were measured with a Cesium vapor magnetometer on the sea floor in Monterey Bay, and at a remote land site. Correlation was found between the geomagnetic activity A-index and both the slope and relative magnitude of the power spectra. More active days showed a greater fall-off as frequency increased, and a higher level of the observed power spectra. Fluctuations averaging 0.1n (sq T)/Hz ... |
|
| Data Acquisition System for Use in the Study of Geomagnetic Variations |
DEC 1980 |
|
| Authors:
Hugh H. Thomas; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The study of the variations in the geomagnetic field requires a small, low power digital acquisition system. This thesis describes the design of a digital data acquisition system for such use. The design uses the complementary metal-oxide-semiconductor (CMOS) version of the INTEL 8048 single chip microcomputer and a high density data recorder. The microcomputers do not take data internally, instead they route data over a separate data bus. Two intermediate ... |
|
| Magnetospheric and Geomagnetic Activity during the First Year (1979) of the SCATHA (P78-2) Satellite Operation |
DEC 1980 |
|
| Authors:
Ching-I. Meng; JOHNS HOPKINS UNIV LAUREL MD APPLIED PHYSICS LAB
|
| This report consists of two parts. The first is a comprehensive analysis of the geomagnetic field variations observed by several networks of ground-based stations to monitor the magnetospheric conditions during the first year of the SCATHA satellite operation in 1979, together with the determination of the most disturbed and quietest days during the 1979 period. The second part is a summary of the scientific results in the investigation of polar ... |
|
| Progress in the Global Standardization of Gravity: An Analysis of the Woollard and Rose International Gravity Values, |
Dec-1980 |
|
| Authors:
George P Woollard; Valerie M Godley; HAWAII INST OF GEOPHYSICS HONOLULU
|
| The history of improvements in the global standardization of gravity values since the advent of high range gravimeters in 1948 is reviewed. In particular the gravity base values given in SEG special publication International Gravity Measurements (Woollard and Rose, 1963) are evaluated against the most recent set of standardized gravity base values, The International Gravity Standardization Net, 1971 (Morelli et al, 1974). Adjunct IGSN 71 values prepared by the U.S. ... |
|
| Experimental Demonstration of Weaver's Model of Magnetic Fields from Ocean Waves |
12 NOV 80 |
24 pages |
| Authors:
Andrew R. Ochadlick Jr; NAVAL AIR DEVELOPMENT CENTER WARMINSTER PA SENSORS AND AVIONICS TECHNOLOGY DI RECTORATE
|
| Magnetic measurements have been made above ocean waves from a stable platform at sea. The results are consistent with the theory of magnetic fields associated with ocean waves. The theory offers the potential to reduce or eliminate ocean wave noise in MAD (Magnetic Anomaly Detection). |
|
| A Cultural Resources Assessment of Selected Magnetic Anomalies, Freeport Harbor, Texas, 45-Foot Project |
NOV 1980 |
|
| Authors:
Clell L. Bond; TEXAS A AND M UNIV COLLEGE STATION CULTURAL RESOURCES LAB
|
| The Texas A & M Cultural Resources Laboratory conducted a series of 26 dives on or near Points 7, 13, 14, 15, 17, and 18 at the Freeport Harbor, Texas, 45-Foot Project. The search teams found an often dredge-disturbed clay bottom and an absence of culturally signigicatn materials at the Corps of Engineers selected anomaly positions. Further work at the investigated points is not recommended. |
|
| Spatial Coherence Measurements and Evaluation of a Noise Reduction Technique for Ambient Noise from 0.3 to 40 Hz |
15 OCT 1980 |
60 pages |
| Authors:
R. J. Dinger; J. A. Goldstein; NAVAL RESEARCH LAB WASHINGTON DC
|
| Measurements of the ambient magnetic field in the frequency range from 0.3 Hz to 40 Hz were made at a mid-latitude location in winter (China Lake, California) and an auroral location in summer (Tromso, Norway). At each location two sensitive triaxial SQUID magnetometers were installed at sites whose separation was varied from 0.5 km to 15 km (in California) and from 0.5 km to 9. 3 km (in Norway). Approximately ... |
|
| Observations of Position, Ocean Depths, and Gravity Taken from the FRAM II and CAMP I Drifting Ice Stations. |
SEP 1980 |
|
| Authors:
B. Allen; J. Ardai; K. Hunkins; T. Lee; T. O. Manley; LAMONT-DOHERTY GEOLOGICAL OBSERVATORY PALISADES NY
|
| This report contains geophysical data collected by the Lamont group at the FRAM II and Camp I drifting stations. These data include station positions determined by satellite navigation, echo soundings, ice floe azimuths, magnetic declination and gravity readings. (Author) |
|
| Some Features of Deep Structure and Origin of Lomonosov Ridge According to Aeromagnetic Data, |
22 AUG 1980 |
|
| Authors:
A. M. Karasik; N. I. Gurevich; V. N. Masolov; V. G. Shchelovanov; FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OH
|
|
| An Overview of Geomagnetic Field Models |
15 AUG 1980 |
|
| Authors:
Robert D. Regan; PHOENIX CORP MCLEAN VA
|
| Over the last decade, the utility of geomagnetic field models or the mathematical representations of the geomagnetic field has expanded considerably, both for civilian and military applications. Such an increase has been accompanied with more interest in models and demands for better accuracies with resultant changes in techniques of model computations and input data requirements. Additionally, such a detailed overview of geomagnetic field models provides a vantage point for reviewing ... |
|
| Indian Ocean Geological, Geophysical and Oceanographic Data Catalog, USNS WILKES, 1977-1979. |
AUG 1980 |
|
| Authors:
Luther Little; Nicholas J. DiPiazza; William J. Vestal; William P. Searcy III; NAVAL OCEANOGRAPHIC OFFICE NSTL STATION MS
|
| During the period of May 1977 to December 1979, the U.S. Naval Oceanographic Office conducted geological, geophysical, and oceanographic surveys in the Indian Ocean from the USNS WILKES. The report summarizes the type, amount, and location of underway and on-station data. Underway data consists of seismic profiles, narrow beam bathymetry, 3.5 kHz subbottom profiles, total magnetic intensity, and sea surface temperature measurements. On-station data includes sediment interval velocity measurements made ... |
|
| The Estimation of Palaeomagnetic Pole Positions. |
JUL 1980 |
|
| Authors:
Geoffrey S. Watson; PRINCETON UNIV NJ DEPT OF STATISTICS
|
| The use of the Fisher distribution to estimate the mean direction of magnetization of a rock at a sampling site is now standard. Sampling sites are chosen to cover 10,000 to 100,000 years to average out the effect of secular variation. The controversy about how to combine these site means has never been satisfactorily resolved. By using statistical models for secular variation, this paper suggests how methods should be derived. ... |
|
| Behavior of High-Latitude Irregularities during Geomagnetic Disturbances. |
24 JUN 1980 |
|
| Authors:
Zwi Houminer; Jules Aarons; AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA
|
| Scintillation observations of VHF and UHF transmissions from geostationary satellites at Goose Bay have been used to study the average characteristics of the high latitude irregularity region. The paper describes the average time development and mean diurnal pattern of irregularities during 58 magnetic storms in 1971-1976. The diurnal variation at Goose Bay shows two peaks of scintillation activity. One peak occurs during the afternoon hours, while the second occurs during ... |
|
| Specific Character of Magnetic Field and Development of Underwater Ridges of Arctic Basin, |
16 JUN 1980 |
|
| Authors:
A. M. Karasik; R. M. Demenitskaya; V. G. Shelovanov; FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OH
|
|
| Low Frequency Geomagnetic Fluctuations (.04 to 25 Hz) on Land and on the Floor of Monterey Bay. |
JUN 1980 |
|
| Authors:
Gerald R. McDevitt; B. Bert Homan; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| A coil antenna consisting of approximately 6000 turns of copper wire was used to measure the horizontal component of fluctuations of the earth's magnetic field on the floor of Monterey Bay in water depth of approximately 50 meters. The results indicate that the power spectral density of the fluctuations varies from 10(nT)-sq/Hz at 0.04 Hz to 0.000001(nT)-sq/Hz at 25 Hz, a monotonic decrease of about 6 dB/octave, except in the ... |
|
| Geomagnetic Activity and the Equatorial Scintillation of Satellite Signals. |
19 MAY 1980 |
|
| Authors:
M. R. Paulson; NAVAL OCEAN SYSTEMS CENTER SAN DIEGO CA
|
| Occurrence and intensity of equatorial scintillation have been correlated with daily summed geomagnetic 3-hour Kp indices, through scintillation data from satellites at two elevation angles for uhf and L-band. They also have been correlated with the individual 3-hour Kp indices and the correlations have been shown as a function of the time of day that the magnetic activity occurred. Correlation values as large as -0.91 and +0.56 were observed. A ... |
|
| Study of Magnetospheric Currents and Resultant Surface Magnetic Variations. |
17 APR 1980 |
|
| Authors:
C. -K CHEN; R. A. Wolf; M. Harel; J. L. Karty; R. W. Spiro; RICE UNIV HOUSTON TX
|
| We have completed computer simulations of the inner magnetosphere, for the substorm-type event of 19 September 1976. Several computer runs have been performed, with various sets of input parameters. Data from the Air Force S3-2 satellite and ground magnetometers were used for model inputs. Model predictions were analyzed and exhaustively compared with data from the S3-2 satellite, the AFGL magnetometer chain and many other sources. Agreement between theory and data ... |
|
| Geomagnetic Index Calculation and Use at AFGWC, |
APR 1980 |
|
| Authors:
Robert D. Prochaska; AIR FORCE GLOBAL WEATHER CENTRAL OFFUTT AFB NE
|
| At Air Force Global Weather Central (AFGWC) several geomagnetic indices to specify the state of the magnetosphere were used. In this paper it introduces the indices of geomagnetic activity most commonly in use by DOD agencies. It discuss the procedures used at AFGCW to compute the indices and briefly describe the uses of each one. |
|
| Phenomenological and Theoretical Studies on Magnetic Indicators of Substorm Activity. |
21 MAR 1980 |
|
| Authors:
Robert L. Carovillano; Robert E. Sheehan; George L. Siscoe; Richard W. Nopper Jr.; Joseph N. Barfield; BOSTON COLL CHESTNUT HILL MA DEPT OF PHYSICS
|
| We report results of studies made on substorm detection, behavior, and relationship to magnetospheric processes. A scheme is developed whereby sub auroral or mid latitude magnetometer stations may be used to detect substorm occurrence. Factors limiting detection quality include longitudinal station coverage, substorm intensity, and local time dependence. Test results from mid latitude stations located in the night sector indicate 100% detection of AE events that exceed 600 gamma and ... |
|
| Geomagnetic Activity and Hale Sector Boundaries. |
FEB 1980 |
|
| Authors:
Henrik Lundstedt; P. H. Scherrer; J. M. Wilcox; STANFORD UNIV CA INST FOR PLASMA RESEARCH
|
| The variation of the geomagnetic activity index Ap at the Interplanetary Magnetic Field (IMF) sector boundaries (+ to - and - to +) has been studied for three solar cycles, separating data into vernal and autumnal equinoxes. It was found that a reported increase in Ap as an effect of a Hale boundary can be better attributed to the occurrence of a negative IMF Bz component in the geocentric solar ... |
|
| AFGL Magnetometer Network - A Program Overview |
01 JAN 1980 |
|
| Authors:
P. Tsipouras; T. Costello; BEDFORD RESEARCH ASSOCIATES MA
|
| The goal of this task is to use the AFGL Magnetometer Network data base to improve the Air Force's ability to specify and predict geomagnetic activity. This information is very useful the studying of propagation of electro-magnetic waves and messages in the atmosphere. Initial efforts are aimed at generating an easily accessible data base for 1-2 years of data. Subsequent work will use the data in spectral and maximum entropy ... |
|
| Investigation of Magnetic Field Phenomena in the Ionosphere. |
JAN 1980 |
|
| Authors:
John F. Devane; Edward A. Johnson; WESTON OBSERVATORY MASS
|
| Weston Observatory (Boston College) has maintained a geomagnetic observatory to continuously monitor changes in the geomagnetic field and to provide standards for magnetic instrumentation and to maintain a coil system in which a wide variety of magnetic instrumentation can be tested and calibrated to support AFGL RESEARCH. The observatories in Project MAGAF have been installed and maintained. The secular change in the geomagnetic field at Weston is detailed for the ... |
|
| Low Frequency Geomagnetic Fluctuations (.01 to 3 Hz) on the Floor of Monterey Bay. |
DEC 1979 |
|
| Authors:
Edmund J. Chaffee; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Using a Cs vapor magnetometer, we observed fluctuations of the total magnetic field in the .01 Hz to 3 Hz frequency range on the floor of Monterey Bay, California. Fourteen hours of data were recorded over a period of six months in 1979 at several depths from 30 to 300 meters. A small, inexpensive recording system was designed and manufactured having a noise floor below 0.001 nTin the frequency range ... |
|
| The Investigation of the Magnetospheric Dynamics in Conjunction with the SCATHA Satellite Observations. |
DEC 1979 |
|
| Authors:
Ching-I. Meng; JOHNS HOPKINS UNIV LAUREL MD APPLIED PHYSICS LAB
|
| This task consists of two parts. The first part concerns (a) the collection and analysis of ground-based and satellite data for the purpose of monitoring the magnetospheric conditions in support of the SCATHA satellite activity at Air Force Geophysics Laboratory, and (b) the technical support in the study of the particle and field data returned by SCATHA satellite. The second part is to analyze observations of auroral phenomena made by ... |
|
| State-of-the-Art for Assessing Earthquake Hazards in the United States. Report 15. Tsunamis, Seiches, and Landslide-Induced Water Waves. |
NOV 1979 |
|
| Authors:
James R. Houston; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
|
| State-of-the-art methods are presented to assess the hazards of tsunamis, seiches, and landslide-induced water waves in the United States. Tsunami hazard maps for the United States are shown that display tsunami elevation zones that have a 90 percent probability of not being exceeded in a 50-year period. Methods used to determine forces exerted on structures by tsunamis are described. Hydrodynamic aspects of seiches and landslide-induced water waves are discussed, as ... |
|
| An Overview of the External Magnetic Field with Regard to Magnetic Surveys. |
01 OCT 1979 |
|
| Authors:
Robert D. Regan; Paul Rodriguez; PHOENIX CORP MCLEAN VA
|
| This report sponsored by the Earth Physics Program of the Office of Naval Research, is an attempt to bring together in a coherent manner, for those involved in magnetic surveys, the relevant aspects of the external geomagnetic field. Although there are several excellant introductory texts on geomagnetism that treat much of this subject (most notably, Sugiura and Heppner, 1968; and Knecht, 1972) it was thought that there was a need ... |
|
| Archive Data Tapes of the AFGL Magnetometer Network. |
20 SEP 1979 |
|
| Authors:
David J. Knecht; AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA
|
| All data returned by the data-collection stations of the AFGL magnetometer Network are recorded automatically on a series of magnetic tapes referred to as the ARCHIVE tapes. On these tapes, data are reordered, to effect grouping by instrument and compressed, to minimize the amount of tape used, but are otherwise in raw form and unedited. This report describes the format and content of these tapes with sufficient precision and detail ... |
|
| A Simple Model of the Magnetosphere. |
12 SEP 1979 |
|
| Authors:
Janet M. Luhmann ; Lynn M. Friesen; AEROSPACE CORP EL SEGUNDO CA SPACE SCIENCES LAB
|
| A phenomenological magnetic field model for the earth's magnetosphere is constructed from a dipole field and a uniform field directed sunward in the northern hemisphere and antisunward in the southern hemisphere. The properties of this simple model are compared with those of several other quantitative models. The present models is found to be more suitable for calculations than some other simple models in cases where the distant(>13 Re) magnetotail configuration ... |
|
| Noise Suppression and Balancing Experiments Using a Superconducting Magnetic Gradiometer. |
SEP 1979 |
|
| Authors:
Ronald E. Sager ; Walter N. Podney; PHYSICAL DYNAMICS INC LA JOLLA CALIF
|
| We present a noise suppression technique which allows detection of tiny fluctuating magnetic gradients in the presence of a very large dc gradient field. We describe our superconducting gradiometer, its response to rotations in an arbitrary magnetic field, and various external sources of noise in the gradiometer output. As ambient dc gradient field is shown to be identical to the gradients produced by some 'equivalent dipole' and gradient noise in ... |
|
| Observations of Position, Ocean Depth, Ice Rotation, Magnetic Declination and Gravity Taken at the FRAM I Drifting Ice Station. |
SEP 1979 |
|
| Authors:
Kenneth Hunkins ; Thomas Manley ; Werner Tiemann; LAMONT-DOHERTY GEOLOGICAL OBSERVATORY PALISADES N Y
|
| The Arctic Ocean north of Greenland is a relatively unexplored area. FRAM I was a research station established on drifting pack ice to carry out geological, geophysical, oceanographic and biological studies in this region. This report contains geophysical data collected at the FRAM I drifting station. These data include station positions determined by satellite navigation, echo soundings, ice floe azimuths, magnetic declination and gravity readings. |
|
| Proceedings of the Air Force Geophysics Laboratory Workshop on Geomagnetism: April 6-7, 1979. |
20 AUG 1979 |
|
| Authors:
Rita C. Sagalyn; Robert O. Hutchinson; Susan Gussenhoven; AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA
|
| On 6-7 April 1979 a two-day workshop on geomagnetism was held at the Air Force Geophysics Laboratory (AFGL). Proceedings of the workshop presented here include: reports on tutorial sessions concerning magnetospheric and geomagnetic pulsations, summaries of contributed papers, descriptions of active magnetometer networks, conclusions of workshop-discussion groups. Special emphasis is given to the use and future potential of the AFGL midlatitude magnetometer chain. (Author) |
|
| MHDEMP Code Simulation of Starfish |
01 AUG 1979 |
|
| Authors:
Steven Chavin; William F. Crevier; Ralph W. Kilb; Conrad L. Longmire; MISSION RESEARCH CORP SANTA BARBARA CA
|
| The magnetic field variations on the ground after Starfish are calculated by the MHDEMP code using input parameters produced by the MICE code. The results agree well with the experimental data at Johnston Island. These magnetic field variations extend over large distances and may cause large potential fluctuations in long-line ground systems. (Author) |
|
| Regional Seismic Wave Propagation. |
31 JUL 1979 |
|
| Authors:
Paul W. Pomeroy; RONDOUT ASSOCIATES INC STONE RIDGE NY
|
| The research reported here was carried out to enhance our understanding of seismic wave propagation at regional distances in the central portion of the USSR. Results in this region are contrasted with those from the Western USSR and with data from eastern North America. |
|
| Preliminary Evaluation of an Algorithm for Analysis of Stationary Random Data from a Multiple-Input Linear System. |
JUL 1979 |
|
| Authors:
Henry Hidalgo; Wasyl Wasylkiwskyj; INSTITUTE FOR DEFENSE ANALYSES ARLINGTON VA SCIENCE AND TECHNOLOGY DIV
|
| This paper deals with a preliminary evaluation of a mean-squared estimated algorithm for the extraction of a signal that is embedded in superposed stationary noise processes. The motivation for this study is the processing and interpretation of data obtained in recent experiments to measure gradients of magnetic fields induced by internal waves in a shallow ocean. The approach used is simulation of the signal and noise processes through construction of ... |
|
| On the Theory and Optimization of Global Point-Mass Expansions of Anomalous Gravity. |
JUN 1979 |
|
| Authors:
John V. Shebalin; NAVAL SURFACE WEAPONS CENTER DAHLGREN LAB VA
|
| The relationship between point-mass and spherical harmonic expansions of anomalous gravity is analyzed. In particular, the spherical harmonic expansion of a point-mass set is determined and used to discuss the nature of point-mass solutions to the problem of modeling anomalous gravity. Also, a 'global error', which arises when a finite spherical harmonic expansion is replaced by a point-mass set, is first defined and then determined, both for the anomalous potential ... |
|
| Power Spectra of Geomagnetic Fluctuations between 0.4 and 40 Hz. |
JUN 1979 |
|
| Authors:
Frederick William Clayton; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| Power spectra of the fluctuations of the geomagnetic field were obtained for the frequency range of 0.4-40 Hz using an optically pumped Cesium vapor magnetometer. The spectra display a gradual decrease in slope at low frequencies with zero slope occurring between approximately 5 Hz and 15 Hz followed by a slight increase in slope. Data was collected at local midnight (0000-0200), local morning (0800-1000) and local afternoon (1600-1800). The morning ... |
|
| Seismic Studies of the Nevada Test Site. |
JUN 1979 |
|
| Authors:
David M. Hadley; Robert S. Hart; SIERRA GEOPHYSICS INC ARCADIA CA
|
| In this report, the following three areas are discussed: (1) Geological and exploration geophysical data for the Yucca Flats area of NTS have been used to develop 3-dimensional models for studies of wave propagation in that basin. Amplitude and waveform complexity is examined for both incoming and outgoing seismic rays as a function of both azimuth and location across the basin. For the incoming case, the direct arrival is only ... |
|
| High-Time Resolution Study of the September 21, 1977 Sudden Commencement Using AFGL Magnetometer Data. |
15 MAY 1979 |
|
| Authors:
Paul F. Fougere; AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA
|
| An SSC, following a solar flare of importance 3B, is seen to travel across the AFGL Magnetometer Network from west to east. The disturbance flattens and decays of it propagates like a plane wave with the stations responding in order of their distance from the sub-solar point. (Author) |
|
| An Electromagnetic Geophysical Survey at an Interior Alaska Permafrost Exposure. |
MAY 1979 |
|
| Authors:
P. V. Sellmann; A. J. Delaney; S. A. Arcone; COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH
|
| Road construction activity near Fairbanks, Alaska, in the late fall of 1977, revealed a large exposure of Fairbanks silt containing numerous massive ice features. These exposures are typical of those found in this region. Thaw, during the summer of 1978, caused the upper ice-rich sections to retreat several meters. Geophysical techniques were utilized over these exposures to determine if resistive anomalies of ice wedge dimension could be detected. Magnetic induction ... |
|
Geomagnetism
