bluuebunny/crossref_metadata_2025_split huggingface dataset:
Speculations on continental crustal evolution
Authors: Meissner Rolf , Mooney Walter D. 
Published: October 2006

The evolution of the continental crust is a topic that has challenged Earth scientists since the earliest hypotheses of crustal evolution were put forth by such luminaries as Hutton, the 18th century Scottish scientist, and later by Stille (Germany), Argand (France), and Dana (United States). Recent geophysical observations provide important constraints on hypotheses of crustal evolution, and the most important of these observations are reviewed in a companion paper [Mooney and Meissner, 1991], henceforth referred to as Paper 1. In this article we briefly speculate on crustal evolution using both geological and geophysical data as guidelines.For the past 25 years, the basic framework for models of the evolution of the Earth's crust and lithosphere has been plate tectonics. This framework has been particularly successful in explaining the processes that form and modify the oceanic crust but has had somewhat more limited success in its application to the continental crust. Some of the basic tenets of plate tectonics, as applied to the continental crust, are listed below. Continental masses coalesce and disperse as ocean basins open and close in the Wilson cycle.
Melt segregation and migration
Authors: Sawyer Ed. W. , Bedard Paul L. 
Published: October 2006

The processes by which melt separates from its associated solids are relevant to a wide range of geological problems. How is melt extracted during anatexis to form migmatites or granites? What drives melt segregation, especially at low melt fractions? What volume fraction of melt can be extracted? How do residual liquids percolate through accumulating crystal piles? How does melt reach high‐level plutons? These and related problems were discussed in a special session, “Melt Segregation and Migration in Partially Molten Rocks,” of the Geological Association of Canada‐Mineralogical Association of Canada (GAC‐MAC) annual meeting in Toronto, May 27–29. This session, sponsored by the MAC, attracted contributions on a wide range of field, structural, geochemical, theoretical, and geophysical studies.All of the field‐based studies brought out the close temporal and spatial association between shear zones and melt segregation. Sally Goodman of the University of Aberdeen showed that migmatization in the Crinan subgroup of the Scottish Dalradian began with metamorphic differentiation and progressed to extensive melting in shear zones associated with the influx of fluids. Although some melt pockets remained, rocks in the shear zone now consist largely of recrystallized restite material. Shearing at the time of melting apparently drove melt segregation, and the possibility that the expelled melt formed the nearby granite bodies is being investigated.
The human factor and global change
Authors: Bush Susan 
Published: October 2006

The ways that human, physical, and biological systems interact are becoming increasingly important to understanding global environmental change and could help clear up many of the uncertainties associated with it, concludes a recent report by the National Research Council's committee on the Human Dimensions of Global Change.Although knowledge of the natural sciences is essential for understanding global change, it is not enough, said Paul Stern, the committee's study director. “Prediction of global change will be flawed unless there is adequate understanding of human activities,” he added
Congress approves NSFs current plan
Authors: Anonymous  
Published: October 2006

Congress has granted final approval, without changes, to the National Science Foundation's operating plan for 1991. NSF projects an 11.2% increase in its budget over last year, to $2,316 billion. The plan awards the largest increase, 46.2% over last year, to the category of education and human resources.Geosciences receive $367 million, an increase over fiscal year 1990's $325 million. This breaks down into $114.52 million for atmospheric sciences (above last year's $104.1 million); $68.33 million for Earth sciences (above last year's $60.11 million); $164.80 million for ocean sciences (over $147.37 million); $14.95 million for the Arctic research program (over $12.45 million); and $5.10 million for science and technology centers (up from last year's $0.98 million). Physics funding increases 4.2%, or $5.2 million, while astronomical sciences receive a 6.2% increase, or $5.67 million.
Another view on IGRF commercialization
Authors: Anonymous  
Published: October 2006

The purpose of this article is to add to Patrick Taylor's arguments against commercialization of the International Geomagnetic Reference Field (IGRF) (Eos, April 16, 1991), and to examine the long‐term future of the global network of magnetic observatories. As chairman of the Fundraising Committee of the International Association of Geomagnetism and Aeronomy, Bill Stuart (Eos, Aug. 14, 1990; Feb. 19, 1991) has proposed selling IGRF as the only way of raising support for the many magnetic observatories facing imminent closure in developing countries.Under the scheme, commercial organizations, such as oil‐drilling and mineral exploration companies, would pay for using IGRF according to some appropriate scale of charges, whereas academic and noncommercial users would continue to have free access. Questions regarding IAGA's legal rights to sell IGRF, and contentious issues concerning the administration, pricing, and policing of the scheme, though of considerable importance, are secondary to the central question of whether IAGA should be engaged in such an exercise.
A closer look at deep crustal reflections
Authors: Percival J. A. , Shaw D. M. , Milkereit B. , White D. J. , Jones A. G. , Green A. G. , Salisbury M. H. , Bursnall J. T. , Moser D. E. , Thurston P. C. , Bailey R. C. , Mareschal M. 
Published: October 2006

Since acquisition of the first crustal‐scale seismic reflection sections, Earth scientists have been intrigued by images of the inaccessibly deep parts of the crust. The pattern of discontinuous subhorizontal reflections at 20–40 km depths has evoked hypotheses as diverse as depositional layering, mafic sills/intrusive layering, shear zones, and fluidfilled fractures. It is clearly important to develop interpretational criteria to relate geological evolution to seismic images.A valid approach, practiced in seismic programs worldwide, is to study regions where the geological history is well understood. For example, the lower crust of the Basin and Range Province has a history of repeated recent mafic underplating, detectable seismically in high refraction velocities and widespread subhorizontal reflections. Such images observed in other extended regions may be interpreted in a similar fashion.
Austin Post receives Hubley Award
Authors: Anonymous  
Published: October 2006

One of the characteristics of the community of scientists and engineers that are working in the snow, ice, and permafrost area is that they have formed a number of organizations, both formal and informal, that concentrate on a specific topic or region and conduct relatively regular meetings of that special interest group on those subjects. Examples of these are the Eastern Snow Conference, the International Conferences on the Physics of Ice, and the International Workshops on the Atmospheric Icing of Structures.One of these groups, the Northwest Glaciologists, recently established an award, the Richard C. Hubley Crystal, which was presented to Austin Post at their last meeting in Seattle, Washington, on November 30, 1990. Seventy‐seven glaciologists were in attendance including representatives of the outposts of the Northwest from Nagoya, Fairbanks, Pasadena, Oslo, and Innusbruck. The following is a short summary submitted by Mark Meier of the Northwest Glaciologists (in their own words, “a unique non‐organization”), some of the background for their establishing the Richard C. Hubley Crystal, Austin Post's contributions that led to his being the first recipient of the award, and his response to receiving the award.
1991 Mineral Physics Student Award
Authors: Anonymous  
Published: October 2006

Thomas S. Duffy of the Seismological Laboratory at the California Institute of Technology has received the Mineral Physics Student Award for 1991. This cash award is given to a student within the field of mineral physics who shows unusual promise, as evidenced by letters of support and material written by the student.In his graduate work with Tom Ahrens at Caltech, Duffy measures sonic velocities in materials under high pressure and temperature conditions. His papers have covered constraints on mantle mineralogy by measurements of seismic velocities in minerals, elasticity measurements on enstatite, and measurements of sound speed under shock. Tom's nomination describes Duffy as “an outstanding young mineral physicist who is very smart and has a great deal of drive and ambition.”
Magellan stops transmitting Venus data
Authors: Simarski Lynn Teo 
Published: October 2006

The Magellan spacecraft stopped sending telemetry data signals back to Earth on January 4, just as it was completing its second mapping cycle of Venus. The apparent cause is a broken transponder, used in the transmission of mapping data. Magellan's troubles are magnified by an interfering "“whistle” that has afflicted signals from the spacecraft's second transponder since last March.The spacecraft has mapped about 97% of Venus' surface, with about 2 more weeks of its second cycle to go, according to David Okerson, mission program engineer. All attempts to fix the transponder that just stopped operating have failed, so efforts are now focusing on the second, “whistling” transponder. If it, too, remains impaired, the spacecraft will have miss an area of Venus that includes three volcanoes—Ushas, Hathor, and Innini. If the transponder problem is not resolved by January 24, Magellan will also not be able to get stereoscopic images of the Maxwell Mons area, considered a high priority for mapping because of the extremely precipitous cliff believed to mark the mountain's western edge.
Keeping JGR manageable
Authors: Bowman J. Roger , Cummins Phil , Kenneth Brian 
Published: October 2006

Recent JGR policies that encourage special sections and eliminate page charges for author‐produced copy have been a boon for JGR‐Solid Earth, at least if the number of pages published is used as the primary measure of success. On the other hand, these policies have not served the interests of individual subscribers.The merit of the material published in the 8,557 pages of the 1990 volume of JGR‐Solid Earth is not in question. As a subscriber whose main interest is in seismology, however, I have several measures of the value and cost of the journal besides the number of published pages. These 8,557 pages of JGR‐Solid Earth occupy 29 cm of shelf space and weigh 15.7 kg. (The June issue alone weighed 1.9 kg!) These are awkward figures for anyone contemplating a long‐distance move or just taking the most recent issue home for the evening.
“Geophysical couples” Discuss jobs, marriage
Authors: Anonymous  
Published: October 2006

Some 90 participants attended an open forum, “Dual Career Couples: Challenges and Opportunities,” on December 9 at the AGU Fall 1991 Meeting in San Francisco. Several couples summarized their experiences in “geophysical marriages” while the audience contributed questions and comments.Being forced to live apart was a common complaint among the married panelists. One couple on the panel—Karen Prestegaard of the University of Maryland and Jim Luhr of the Smithsonian Institution's Department of Mineral Physics—have been able to live together only 2 years out of the last 10. Although employer guidelines do not officially prohibit hiring couples, Prestegaard and Luhr expressed frustration that many institutions not only will not do so, but also will not help the second partner find a job nearby.
Hinze appointed Editor of JGR‐Solid Earth
Authors: Anonymous  
Published: October 2006

William J. Hinze of Purdue University has been appointed editor of the Journal of Geophysical Research‐Solid Earth. The previous multi‐editor set‐up, based on disciplines, has been consolidated into a single editorship responsible for the entire journal.“As I pick up the reins of JGR‐Solid Earth” Hinze says, “I look forward to the challenges and opportunities of making our journal even more useful and significant, not only to the members of the AGU sections it serves directly, but to all those interested in Earth science.”
SAR observations of the Gulf Stream during SWADE
Authors: Vachon Paris W. , Liu Antony K. , Mollo‐Christensen Erik 
Published: October 2006

In this article, we present and discuss some airborne synthetic aperture radar (SAR) observations of the Gulf Stream that were made by the Canada Centre for Remote Sensing (CCRS) during the Surface Wave Dynamics Experiment (SWADE) [see Weller et al., 1991]. The CCRS CV‐580 aircraft is equipped with a C‐band SAR [see Livingstone et al., 1988] and was flown on four separate occasions during the third SWADE intensive observation period in February and March 1991.While the purpose of SWADE is to study wind wave dynamics, a northward meander brought the Gulf Stream over the continental shelf and into the SWADE observational area to the east of Wallops Island, Va. The approximate location of the Gulf Stream, based upon an operational oceanographic feature analysis using infrared imagery from the Advanced Very High Resolution Radiometer (AVHRR) and buoy data from the National Oceanic and Atmospheric Administration, is shown in Figure 1.
Measuring the Earth to within an inch using GPS satellites
Authors: Blewitt Geoffrey 
Published: October 2006

A recently developed technique for “measuring the Earth” was demonstrated in 1991 using data from an experiment involving a world‐wide network of receivers that track satellites of the Global Positioning System (GPS). Recent results indicate that distances between points separated by as much as 10,000 km on the surface of the Earth can be determined at the 2 cm level, and that the position of the pole of rotation at the Earth's surface can be estimated daily to better than 2 cm. Achieving this level of accuracy in a reliable, economical way is an important step towards building our understanding of the Earth as a rotating, deforming body.Funded by NASA's Solid Earth Science Program, the Jet Propulsion Laboratory coordinated participation of many international institutions in a 3‐week experiment in January–February 1991 called GPS for International Earth Rotation Service (IERS) and Geodynamics '91 (GIG'91). Twenty‐one receivers developed by J PL and scores of commercial receivers were simultaneously deployed. Several independent groups around the world analyzed the data and presented results at meetings in the summer and fall of 1991.
Bromley discusses policy with scientific societies
Authors: Cole Stephen 
Published: October 2006

D. Allan Bromley, President Bush's science advisor, met with presidents and executive officers of two dozen physical science and mathematics societies on January 22 to discuss major issues affecting the scientific community and federal science policy. AGU President G. Brent Dalrymple presented one of four talks given at the meeting on the issue of support for small science.Bromley invited the society leaders to meet with his staff on the Office of Science and Technology Policy in an effort to tap the expertise of scientific societies in formulating science policy. AGU Executive Director Fred Spilhaus remarked that he was impressed by the openness of the meeting and the obvious value Bromley placed on the societies' input.
NSF releases FY 1992 current plan
Authors: Simorski Lynn Teo 
Published: October 2006

The National Science Foundation has released its current plan for fiscal year 1992, which details how it will allocate its budget from October 1991 to September 1992. NSF received an overall increase of 11.12%, almost the same as last year's 11.2% increase.Education and human resources garnered the greatest increase of any category in the foundation for FY 1992, representing a 44.25% increase over FY 1991. The growth in this directorate's allotment, in fact, represents 55.41% of the foundation's entire increase this year. Education and human resources received $220 million in the 1990 plan, $322 million in the 1991 plan, and $465 million in 1992.
Io and Jupiter: The volcano‐magnetosphere connection
Authors: Schneider Nick , Spencer John 
Published: October 2006

In the interlude between spacecraft encounters with Jupiter, Earth‐bound observers using clever and powerful techniques have made substantial headway in monitoring two major phenomena: volcanos on Jupiter's moon Io (most active in the solar system) and Jupiter's magnetosphere (largest and densest of all the planets). While these two may seem unrelated, planetary scientists believe they are quite closely tied. Astronomers are working together to probe the fundamental and enigmatic connection between volcanos and magnetospheres.Volcanic activity on Io is powered not by radioactive heating, as it is on Earth, but by the continual flexing of Io by Jupiter's intense gravitational field, which generates heat as in a rapidly flexed tennis ball. Most of this heat is eventually radiated into space from a series of hot volcanic centers, or “hot spots,” where the surface is up to several hundred degrees hotter than its surroundings. The heat radiation is so intense that Io literally “glows in the dark” at infrared wavelengths, allowing astronomers with infrared telescopes to follow the frequent changes in the level of volcanic activity.
Bush cancels CRAF, closes out Magellan
Authors: Cole Stephen 
Published: October 2006

In response to the Bush administration's announcement last week that funding for the Comet Rendezvous/Asteroid Flyby mission and continued Magellan operations has been eliminated from the fiscal year 1993 budget request, NASA has started the process of shutting down both missions. CRAF is expected to close down completely by October and Magellan's current radar mapping will be eliminated to stretch out 1992 funds through early 1993, when the spacecraft will be turned off.According to the president's 1993 budget report to Congress, CRAF was terminated “because the scientific benefits of this mission no longer justify the investment. In order to contain cost growth, the scope of the CRAF mission was recently reduced by deleting the comet penetrator and several other instruments. Thus, much of the planned science was already lost.”
Tough budget year ahead, says NASA's Fisk
Authors: Cole Stephen 
Published: October 2006

Lennard Fisk, head of NASA's space science and applications division, painted a bleak picture for space scientists on February 14 as the Bush administration's fiscal 1993 budget headed to Congress. Speaking at the annual meeting of the Space Science Working Group in Washington, D.C., Fisk said “It's going to take a miracle to get the $2,985 billion request” for space science in this year's NASA budget.Fisk held out no hope that programs already cut from the budget, such as the Comet Rendezvous/Asteroid Flyby mission, would be reinstated. The CRAF cancellation was “a $50 million issue in fiscal 1993,” said Fisk, “and it was $50 million that simply wasn't there.” His office “was under enormous pressure to take something off the plate,” he said.
Kuwait oil spill studied
Authors: Bush Susan 
Published: October 2006

More than a year after the Persian Gulf War, scientists are still trying to assess the environmental impact of the estimated 6–8 million barrels of oil that were dumped into the gulf and to understand the environmental processes that take place in such a disturbance. Many atmospheric studies were done in the months immediately following the war, but oceanographic studies have been slower in getting started.The National Oceanic and Atmospheric Administration is currently spearheading a major oceanographic study being undertaken in the Persian Gulf by the research vessel Mt. Mitchell. The ship left its home port of Norfolk, Va., in mid‐January and arrived in Muscat, Oman, on February 16 to begin a 100‐day oceanographic and environmental survey. The six‐leg cruise will feature physical oceanography, near‐shore, and marine life studies.
Senate approves energy bill
Authors: Bush Susan 
Published: October 2006

The controversial National Energy Security Act of 1992 (S2166) was approved by the Senate in a 94‐4 vote on February 19 after a circuitous route through the chamber. The original energy bill, SI220, was introduced last summer and was blocked from coming to the Senate floor by a filibuster. The new bill is considerably different from the original energy bill.The sponsor of the bill, S. Bennett Johnston (D‐La.), and cosponsor Malcolm Wallop (R‐Wyo.) agreed to abandon certain controversial components in order to keep the bill moving. The main program dropped is the proposal to open parts of the Arctic National Wildlife Refuge (ANWR) to oil and gas drilling. Environmentalists were opposed to the drilling and were able to block the entire bill last fall, so Johnston agreed to abandon the provision.
“Flat‐Venus Society” organizes
Authors: Morrison David 
Published: October 2006

This is a call for the formation of a Flat‐Venus Society. In the face of a media blitz that conveys the impression that Venus is characterized by soaring mountains and deep canyons, a dedicated group is needed to promote the fact that our sister planet is mostly flat, rolling plains.The beautiful and widely publicized “three‐dimensional images” and video “flyovers” of Venus released by NASA and the Magellan Project at the Jet Propulsion Laboratory all have a vertical exaggeration of 23:1. This distortion greatly exceeds that normally used even by geologists.
Panel drafts position on U.S. science budget
Authors: Anonymous  
Published: October 2006

The AGU panel charged with writing the Union position on the U.S. fiscal 1993 budget met at AGU Headquarters on February 27 to draft their statement and hear from representatives of federal science agencies. The panel's position statement is expected to be completed by the end of March, pending approval by the AGU Council.AGU has drafted positions on the U.S. science budget since 1990. This year's panel includes Terry E. Tullis (chair), Brown University; H. Frank Eden, General Electric Astro Space; Thomas E. Pyle, Joint Oceanographic Institutions, Inc.; Thomas Potemra, Johns Hopkins Applied Physics Laboratory; David W. Simpson, Incorporated Research Institutions for Seismology; Steven W. Squyres, Cornell University; and Eric F. Wood, Princeton University.
Hydrology wins one, loses one
Authors: Simarski Lynn Teo 
Published: October 2006

Hydrologists are lauding the creation of a program for basic hydrologic research within the National Science Foundation, even while another formerly substantial source of funding is drying up at the U.S. Geological Survey. Both events are part of the proposed federal budget for fiscal year 1993.The good news is NSF's proposal for a $2.5 million program intended to fund “basic research dealing with the Earth's hydrologic cycle and the role of water on or near the continental surfaces of the Earth.” According to NSF and hydrologists outside the agency, the program grew out of recommendations from a National Research Council committee that were published in 1991 as Opportunities in the Hydrologic Sciences. The year before, AGU recommended that “NSF take steps to establish a unified program in hydrologic science that is commensurate with the importance of water in Earth processes at all scales.” In its official position on this issue, AGU described NSF's existing support for hydrologic science as fragmented and unstable, impeding the maturation of this area “as a distinct geoscience.”