bluuebunny/crossref_metadata_2025_split huggingface dataset:
A fine‐particle sodium tracer for long‐range transport of the Kuwaiti oil‐fire smoke
Authors: Lowenthal Douglas H. , Borys Randolph D. , Rogers C. Fred , Chow Judith C. , Stevens Robert K. , Pinto Joe P. , Ondov John M. 
Published: February 2008

Evidence for long‐range transport of the Kuwaiti oil‐fire smoke during the months following the Persian Gulf War has been more or less indirect. For example, high concentrations of aerosol particles containing soot and oil‐combustion tracers such as vanadium observed at great distances from the Middle East may have come from sources other than the oil fires. However, more‐recent data on the aerosol chemistry of Kuwaiti oil‐fire plumes provides a direct link between those fires and aerosols collected at the Mauna Loa Observatory (MLO) during the late spring and summer of 1991.By itself, temporal covariation of fine‐particle concentrations of elemental carbon, sulfur, and the noncrustal V / Zn ratio in MLO aerosols suggested a link to large‐scale oil‐combustion sources, but not necessarily to Kuwait. However, high concentrations of fine‐particle (0.1–1.0 µm diameter) NaCl were observed in the “white” oil‐fire plumes over Kuwait during the summer of 1991. Further analysis of the Mauna Loa data indicates strong temporal correspondence between the noncrustal V / Zn and noncrustal Na / Zn ratios and strong consistency between the noncrustal Na to noncrustal V ratios found at Mauna Loa and in the Kuwaiti oil‐fire plume. In the absence of other demonstrable sources of fine‐particle Na, these relationships provide a direct link between the Kuwaiti oil fires and aerosol composition observed at MLO.
Preliminary results on the oxygen isotopic composition of the lower crust, Kilbourne Hole Maar, New Mexico
Authors: James David E. , Padovani Elaine R. , Hart Stanley R. 
Published: February 2008

18O/16O ratios measured in deep crustal xenoliths from Kilbourne Hole maar, New Mexico show that the oxygen isotopic composition of the lower crust of that region is grossly heterogeneous. Xenoliths derived from similar crustal depths vary in δ18O by nearly 6‰, although the xenoliths are individually in internal oxygen isotopic equilibrium. Mafic granulites (including charnockite), probably of mantle origin, have δ18O of about 6.2 to 6.3‰ and correspondingly low 87Sr/86Sr ratios (0.703 to 0.707). Garnet granulites, apparently the residue of partial fusion of pelitic sedimentary rock, have δ18O ranging from about 9‰ to 12‰ and correspondingly high 87Sr/86Sr ratios (0.71 to 0.78).No evidence is found for extensive oxygen exchange over large distances in the anhydrous lower crust beneath Kilbourne Hole. Absence of regional isotopic equilibrium indicates that even at melting or near melting temperatures the oxygen isotopic identity of the protolith can be preserved over long periods of time. We conclude that there is little reason to postulate that massive oxygen exchange with a mantle‐like reservoir is a general phenomenon of the lower crust.
Paleomagnetic results from the Upper Cretaceous Maudlow and Livingston formations, southwest Montana
Authors: Swenson Paul , McWilliams Michael 
Published: February 2008

A paleomagnetic investigation of welded tuff units from the Late Cretaceous Livingston and Maudlow Formations was undertaken to refine the Late Cretaceous to Paleocene APWP for cratonic North America. After progressive AF and thermal demagnetization, the Maudlow Formation (46.1°N, 248.9°E) yields a paleomagnetic pole at 70°N, 208°E (11 sites, A95 = 9°, K = 22). Tectonic correction improves the directional grouping, and the change is statistically significant. Two normal polarity intervals bounding a single reversed polarity interval are present. We interpret the reversed interval to be Chron 33r, on the basis of: [1] stratigraphic correlation of the Maudlow Formation with the Campanian Sedan Formation located 40 km to the east, and [2] K‐Ar dates of 83 ± 2 Ma at the middle of the sampled section and 74.9 ± 1 Ma near the top of the sampled section.The Livingston Formation (45.5°N, 250.1°E) yields a high Hc magnetization with a negative fold test, suggesting a post‐folding secondary magnetization. The Livingston mean direction yields a paleomagnetic pole at 72°N, 218°E (10 sites, A95 = 4°, K = 107) and is clearly distinguishable from a co‐existing lower Hc component reflecting a recent viscous overprint. We interpret the high Hc magnetization as Late Cretaceous to Paleocene in age.Neither the Maudlow Formation pole nor the pole derived from the high Hc overprint in the Livingston Formation agree with previously published poles for either the Late Cretaceous or Tertiary, but they do lie on a simple continuation of the APWP between Late Cretaceous and Paleocene mean poles. Secondary magnetizations found in the Franciscan Complex of California also yield poles which lie on a proposed extension of the APWP. If the Franciscan secondary poles represent an overprint event associated with early Tertiary accretion, and if the Livingston secondary pole represents a deformational event related to Laramide uplift of the nearby Beartooth Range, then together these three poles suggest that the North American APWP may continue farther to the east and south to define a Cretaceous‐Tertiary cusp.
Iridium‐bearing sublimates at a hot‐spot volcano (Piton De La Fournaise, Indian Ocean)
Authors: Toutain Jean‐Paul , Meyer Georges 
Published: February 2008

Sublimates and incrustations derived upon the cooling of volcanic gases have been collected on various sites (Piton de la Fournaise, Poas, Momotombo, Etna, Ardoukoba and Erta‐Ale). They have been analysed for Ir and other volatile elements (Se, As, Cu, Au, Ag, Pb, Tl) by means of instrumental neutron activation analysis (INAA) and proton induced X‐Ray emission (PIXE). Among the investigated volcanoes, only Piton de la Fournaise is found to release detectable amounts of iridium. Ir in Piton de la Fournaise sublimates is associated with F‐minerals. This confirms its gaseous transport as a volatile fluoride compound.Iridium seems to be preferentialy released by hot‐spot type volcanoes, and its detection in Piton de la Fournaise sublimates provides a positive argument in favour of a volcanic hypothesis to explain the KTB events.
Lunar seismology: The internal structure of the Moon
Authors: Goins N. R. , Dainty A. M. , Toksöz M. N. 
Published: February 2008

Tables A1–A4 and Figures A1–A3 are available with entire articleon microfiche. Order from American Geophysical Union, 2000 Florida Avenue, N.W., Washington, D.C. 20009. Document J81‐003;$1.00. Payment must accompany order.The arrival times of direct P and S waves, measured on seismograms recorded from natural lunar seismic events, have been analyzed using linearized inversion and parameter search methods to simultaneously determine event locations, origin times, and structural parameters (seismic velocities). Polarization‐filtered record section plots are correlated with theoretical travel time curves to identify later phases and obtain additional structural and velocity information. Shear wave amplitudes plotted as a function of distance provide data on the existence and magnitude of seismic velocity gradients in the interior. These studies are used to delineate the structure of the moon below the crust to a depth of about 1100 km. This structure has been divided into an upper and a lower mantle. The upper mantle, from 60‐ to 400‐km depth, has average seismic wave velocities of Vp = 7.70 ±0.15 km/s and Vs = 4.45 ± 0.05 km/s with corresponding Q values (taken from the literature) of Qp ∼ 5000 and Qs ∼ 3000. The shear wave velocity decreases with a negative gradient of at most −6 × 10−4 km/s/km, implying a Vs variation of from 4.57 km/s at 60‐km depth to 4.37 km/s at 400‐km depth; this decrease can be accounted for by increasing temperature, and so no major compositional gradient is required in the upper mantle. A small negative P wave velocity gradient may also be present. Between 400‐ and 480‐km depth there is a transition zone with a sharply decreasing shear wave velocity and possibly an accompanying small decrease in Vp. The dominant shear velocity decrease may occur at a 480‐km interface and may represent a compositional change, although the effects of increased temperature cannot be totally ruled out. The lower mantle extends from 480‐km depth to at least 1100‐km depth; few seismic waves recorded by the lunar network penetrate below 1100 km. The average velocities are Vp = 7.6 ± 0.6 km/s and Vs = 4.2 ± 0.1 km/s. Q values (taken from the literature) are Qp ∼ 1500 and Qs ∼ 1000. Below 1100 km there is some indication that the attenuation may increase still further for shear waves, with Qs dropping to a few hundreds or less. This seismic model of the moon is well constrained, with uncertainties on the above values given explicitly by the analysis methods, and so it serves as a strong control on the present‐day lunar compositional and thermal structure.
John C. Jamieson January 5, 1924, to June 26, 1983
Authors: Schock R. N. 
Published: February 2008

John Calhoun Jamieson (Figure 1) was a rare individual who combined unusual scientific talents with a profound respect for his fellow scientists. This special section pays respect to his memory in a way that he truly would have enjoyed—a collection of papers on some of his favorite subjects.John devoted a major part of his life to high‐pressure physics and geophysics. His achievements in this regard are extraordinary and form the basis for much of what we now expend a great deal of effort trying to better understand. To gain insight into the intimate connection between John and high‐pressure science, we must go back to his early career. He was born and raised in St. Joseph, Missouri, and entered the University of Chicago during the early days of World War II. Like many of the students of that day, he subsequently enlisted in the military service. He served as an army weather observer in the Far East. After the war, he returned to Chicago and took his first degree in 1947. He received his Master's degree in 1951 and received one of the first National Science Foundation awards for graduate work in 1952.
Magnetospheric physics: Magnetic fields
Authors: Russell C. T. 
Published: February 2008

Progress in magnetospheric physics during the last quadrennium was not achieved through any one or a number of significant new discoveries or breakthroughs. Rather the advance was manifested more in gradual changes in the collective magnetospheric consciousness: the spreading acceptance that the magnetosphere is indeed ‘open,’ the increasing awareness of the key role of magnetospheric dynamics (substorms) in governing the various magnetospheric processes, a deeper appreciation of the role of electric fields and currents parallel to the magnetic field, the unfolding of the complexities of the earth's bow shock and associated phenomena, a strengthening attack on the merging process via theoretical and laboratory work, and the generation by several groups of magnetospheric magnetic field models based on observational data.The quadrennium also appears to have marked the end of the exploratory phase of magnetospheric studies with the launching of spacecraft into the last unexplored reaches of the magnetosphere and the resultant discovery and investigation of the polar cusp, at the boundary between the closed and open field lines over the day side magnetosphere, and the plasma mantle, a boundary layer of flowing plasma in the high‐latitude magnetotail. New records for closest boundary positions were established during this period. Previously, the magnetopause had been observed at synchronous orbit on ATS 1. However, in March 1970, even the shock crossed synchronous orbit, and solar wind plasma was detected at synchronous orbit. Then in August 1972, Explorer 45 crossed the magnetopause at 5.2 RE. If it is assumed that the magnetopause and shock surface simply changed scale sizes, the ATS 5 observation of solar wind represents the greater magnetospheric distortion.
Planetary magnetospheres
Authors: Hill T. W. , Michel F. C. 
Published: February 2008

The study of extraterrestrial planetary magnetospheres during the past 4 years has experienced a dramatic growth in the availability of observational data and a concomitant growth in the level of scientific interest comparable to the experience of the early 1960's in the study of earth's magnetosphere. Owing in large part to the success of space probes to our four nearest neighbor planets, the domain of magnetospheric physics has grown from the study of ‘the magnetosphere’ into the study of ‘planetary magnetospheres.’It has now become possible to identify three rather different categories of planetary magnetospheres: (1) intrinsic slowly rotating magnetospheres, (2) intrinsic rapidly rotating magnetospheres, and (3) induced magnetospheres. By ‘intrinsic’ we mean that the planet possesses a sufficiently strong magnetic field to hold the solar wind off its surface; by ‘induced’ we mean that the planetary field exists mainly by virtue of the solar wind interaction with the planet. The distinction between ‘rapidly rotating’ and ‘slowly rotating’ is a quantitative one, indicating whether or not the structure and dynamics of the magnetosphere are influenced strongly by the rotational energy of the magnetospheric plasma. Thus although corotation in earth's magnetosphere is a well‐documented fact, this rotation is sufficiently slow that it can be safely ignored in most considerations of the overall dynamics of the magnetosphere, so that earth's magnetosphere is slowly rotating by the above definition.
Magnetospheric plasma wave research 1975–1978
Authors: Shawhan Stanley D. 
Published: February 2008

In this review the term “plasma wave” is used to denote all waves which are generated in the magnetospheric plasma or which have their wave characteristics significantly modified on propagation through the magnetosphere. These plasma waves are both electromagnetic and electrostatic and are generally generated by the conversion of free energy within the plasma into wave energy through a variety of plasma‐wave processes. Plasma waves may in turn interact with plasma particles locally or at remote locations in the magnetosphere to modify the particle populations leading to such phenomena as particle precipitation.Plasma wave research has led to the identification of numerous plasma wave phenomena within the terrestrial magnetosphere. Many of these plasma wave types are associated with the different regions of the magnetosphere as depicted in Figure 1. A listing of the location of these plasma wave types along with the observed frequency range and a description of the wave properties is given in Table 1. Within the magnetosphere, detected plasma waves range in frequency from millihertz—well below the ion gyrofrequency at the bow shock—to 10 megahertz—approximately the electron plasma frequency in the ionosphere. Within the Jovian magnetosphere plasma wave phenomena extend up to 40 MHz which is the maximum electron gyrofrequency in the Jovian ionosphere.
Polar motion and Earth rotation
Authors: McCarthy Dennis D. 
Published: February 2008

During the reporting period 1975–1978, the activity in the field of polar motion and Earth rotation in the United States has been concerned with the continuation of regular observations of polar motion and the rotational speed of the Earth, improvement in the present observational techniques, development of new observational techniques and the analysis of the observations in relation to geophysical phenomena. Significant work has been accomplished in each of these areas, and these efforts are summarized separately in this report.ObservationsClassical observations of the variation of astronomic latitude at the International Latitude Observatories at Gaithersburg, Maryland and Ukiah, California were continued by the National Geodetic Survey of the National Ocean Survey. These observations were made with the same visual zenith telescopes that have been used in the past observations. The data were transmitted to the Central Bureau of the International Polar Motion Service in Mizusawa, Japan, and to the Bureau International de l'Heure in Paris, France. Results are listed in the annual publications of the IPMS and the BIH.
Numerical models of ocean circulation and climate interaction
Authors: Haney Robert L. 
Published: February 2008

This article reviews recent advances in ocean circulation models and climate interactions. Related reviews of one‐dimensional models and models of equatorial and polar regions are given in this Quadrennial Report by Garwood [1979], O'Brien [1979] and Baker [1979], respectively. Related reviews of climate are given in the Meteorology section of the Quadrennial Report by Gates [1979], Kutzbach [1979], Perry [1979], and Rotty and Marland [1979].Several detailed review articles on ocean circulation models and climate were written in the last four years. National Academy of Sciences [1975], U. S. Committee for GARP [1975] and WMO/ICSU [1975] give the status at the beginning of this review period while Pond and Bryan [1976] and Holland [1977a] represent more recent reviews. Kraus [1977] contains review articles on modeling the upper ocean, while Gribbin [1978] contains review articles on the ocean's role in climatic change. The latest detailed reviews of ocean circulation models and their relation to climate were presented at a JOC/SCOR Joint Study Conference held in Helsinki in May, 1977 [WMO/ICSU, 1977]. Many of these reviews will be published in a forthcoming issue of Dynamics of Atmospheres and Oceans. The present review begins with studies of the possible effect of ocean temperature variabilities on the atmosphere, and then proceeds to studies using idealized basin models, world ocean models, and finally coupled ocean‐atmosphere models.
Asteroids and comets
Authors: Chapman Clark R. 
Published: February 2008

Asteroids and comets are populations of countless bodies ranging downwards in size from Ceres, which is about 1000 km in diameter. Although they constitute a virtually negligible fraction of the mass of the solar system, their physical/chemical properties and locations in the system are of particular interest, since they provide most of our observational and experimental clues about the earliest epochs of solar system history. This is particularly due to the fundamental role of meteorites in planetary science; meteorites are fragments of asteroids and comets, although they are treated in this review only tangentialIy. In addition, the ongoing behavior of asteroids and comets (primarily their response to the interplanetary radiation and impact environment) provides interesting insight to unusual physical and geological processes.Both asteroids and comets have been the subject of an important international meeting during the period covered by this report. A comprehensive book and a special issue of a journal emanated from each conference (Asteroids. Gehreis, ed., 1979, and Icarus 40. 1979; Comets. Wilkening, ed., 1982, and Icarus 47. 1981). Particularly in the case of comets, for which the book was published in mid‐1982, it would be superfluous to treat the pre‐1982 literature in great detail. More has happened since the 1979 publication of the Asteroids book, so I rely more on subsequent journal publications about asteroids.
Polarization of Ionospherically Propagated HF Radio Waves with Applications to Radio Communication
Authors: Epstein M. R. 
Published: February 2008

Sweep‐frequency CW radio signals transmitted over 1300‐km north‐south and 1900‐km east‐west temperate‐zone paths were received 24 hours per day for 21½ ‐day periods. Measurements of the incoming one‐hop F‐layer polarization, as a function of time‐of‐day and radio frequency, indicate that daytime rates of change of polarization rotation with frequency (at an instant of time) average 1 turn/MHz over the north‐south path and 0.25 turn/MHz over the east‐west path. These values are in good agreement with computer raytracing predictions of the rates of change of polarization rotation with frequency over similarly disposed paths. It was observed that nighttime polarization rotation rates are about 1 to 4 times as high as those measured during the day. It was also experimentally found that the rate of change of the incoming polarization with frequency first decreased and then increased with incoming radio frequency, the minimum rate occurring near 0.8 MOF0. Daytime rates of polarization rotation with time (at a given frequency) average 0.25 turn/min. The polarization rotation rates with time do not appear to vary either with path azimuth or transmitted radio frequency. Near‐zero rates of polarization rotation with time occur for much of the nighttime period. Large fluctuations in the polarization variations occur with both time and frequency throughout the day.Polarization measurements made with signals that were reflected from a nonblanketing, nighttime sporadic E layer of about two hours duration indicate that, for this layer, circumstances other than polarization effects, probably multipath, determine much of the observed signal strength variations with frequency and time.The results suggest that for round‐the‐clock temperate zone propagation, when linearly polarized antennas are employed, a qualitative threshold for envelope distortion of broadband signals (due to variation in the incoming polarization with frequency) occurs when signal bandwidths exceed approximately 100 kHz for north‐south paths and 400 kHz for east‐west paths. The effects of such distortion may be reduced either by operating near 0.8 MOF0 or by the use of circularly polarized antennas.
Preliminary Results of Measurements by Space Probes Venera 5 and Venera 6 in the Atmosphere of Venus—Summary*
Authors: Avduevsky V. S. , Marov M. Ya , Rozhdestvensky M. K. 
Published: February 2008

The automatic interplanetary stations Venera 5 and Venera 6 reached Venus on May 16 and 17, respectively, and made measurements of the nightside atmosphere in the equatorial plane at a distance of 2700 km from the dawn terminator. The most probable distance between the points where the stations entered the atmosphere was about 300 km. The detailed description of the probe design may be found in Pravda [1969].The present paper analyses parameters of the planetary atmosphere based on the results of the direct measurements of pressure and temperature. A tentative model of the atmosphere can be constructed on the basis of the Venera 5 and Venera 6 in‐situ measurements together with the earlier results of Venera 4 [Avduevsky et al., 1968, 1969] and Mariner 5 [Kliore et al., 1969].
Foreword
Authors: Findlay John W. 
Published: February 2008

The articles in this issue were selected from 40 papers presented at a symposium in Charlottesville, Virginia, on April 13 through 15, 1970. The symposium was held at the National Radio Astronomy Observatory and was sponsored by URSI and the NRAO. The members of the organizing committee were: Prof. M. H. Cohen, California Institute of Technology; Dr. J. W. Findlay, National Radio Astronomy Observatory; Dr. D. L. Jauncey, Center for Radiophysics and Space Research, Cornell University; Dr. K. I. Kellermann, National Radio Astronomy Observatory; Dr. J. L. Locke, National Research Council, Ottawa, Canada; Prof. O. E. H. Rydbeck, Chalmers University of Technology, Gothenburg, Sweden; and Dr. V. V. Vitkevich, Lebedev Physical Institute, Moscow, USSR.The purpose of the symposium was the exchange of information between radio astronomers and workers in disciplines such as geodesy and relativity, in which the very long baseline interferometry technique can be valuable.