bluuebunny/crossref_metadata_2025_split huggingface dataset:
Compiling all the world's magnetic anomalies
Authors: Reeves Colin , Macnab Ron , Maschenkov Sergei 
Published: October 2006

When the ultimate textbook of geology is written, several thematic maps of the world will be cited as conclusive evidence of global tectonics. Examples would be the map of global seismicity that shows just how neatly the vast majority of earthquakes are confined to the plate margins [Simkin et al., 1989] and the map showing the ocean floor topography that has been created, mostly during the last 150 Ma of Earth's history [Smith and Sandwell, 1997]. Visionaries worked out the principles of plate tectonics on much more limited datasets, but extending the principles to understanding the geology of the most remote corners of the globe—and seeing world geology as a true global entity—demands global maps.The magnetic “stripes” of the ocean floor and their symmetry around spreading‐axes can be demonstrated on a few profiles but, so far, only for the North Atlantic and Arctic Oceans have complete magnetic anomaly maps been published [Verhoef et al., 1996]. The much more complex geology of the remaining 90% of Earth's history is preserved in the continents and uniquely revealed—even below extensive areas of younger cover—by continental magnetic anomaly maps. A magnetic anomaly map of the whole world would be a map of some significance alongside these others.
Database of geomagnetic observatory monthly means seeks contributors
Authors: Alexandrescu Mioara 
Published: October 2006

The Department of Geomagnetism of the Institut de Physique du Globe de Paris (IPGP) has compiled a new global database of monthly mean values of geomagnetic elements. This database was originally compiled for a study of “geomagnetic jerks”—apparent sudden step changes in secular acceleration, either side of which the secular variation appears to be approximately linear—for which time series of annual mean values had been the principal source of observational data.Researchers at IPGP encourage geomagnetic observatories throughout the world to submit their monthly mean values for inclusion in the database as soon as possible at the end of each month. The values submitted must be at least provisionally corrected to absolute values at the reference point of the observatory. The preferred method to submit data is by e‐mail in a specified format, but observatories that lack e‐mail facilities may send their results by fax or mail.
Seismic monitoring and activity increase in California Caldera
Authors: Foulger G. R. , Malin Peter E. , Shalev E. , Julian Bruce R. , Hill David P. 
Published: October 2006

Intense seismicity in the Long Valley caldera area of California last summer may have been hydrothermally driven and triggered by escalating magmatic unrest in the resurgent dome area, results from the MAMMOTH 97 Seismic Experiment suggest. The experiment involved enhanced seismic monitoring in an area that is already closely watched for earthquake activity. Sophisticated instruments were placed in the caldera's south moat section, Mammoth Mountain, and the Casa Diablo geothermal area (Figure 1). In early July, just as the enhanced network became fully operational, there was a major increase in seismic activity.Preliminary analysis has yielded new insights into the structure and tectonics of the south moat and suggests the activity occurred above a vertical, east‐west trending, dike‐like structure beneath the moat. A series of vigorous swarms was accompanied by accelerated inflation of the resurgent dome (Figure 2). The permanent network in the area, using single‐component analog instruments, recorded more than 1,600 earthquakes of magnitude up to 3.5 during July and August, but the MAMMOTH network, with three‐component digital instruments, located about six times as many (Figure 3). About 63 “long period” (LP) earthquakes west of Mammoth Mountain were also recorded (Figures 1 and 4).
Global Warming: The Complete Briefing (Second Edition)
Authors: Hartmann Dennis L. 
Published: October 2006

Enough coal exists to sustain world energy consumption growth through at least the end of the next century. If fossil carbon fuel consumption continues to increase at current rates, however, atmospheric carbon dioxide concentrations will likely more than double, probably leading to significant warming of global climate, shifts in regional climates, and sea‐level rise. Scientists and citizens throughout the world are discussing what should be done about the effects of our energy economy on the global environment.The issue is very broad and engaging, ranging from basic issues of geoscience to economics to fundamental value systems, and it has mobilized great economic interests and concern for our global environment. We live in an interesting time when human activities have begun to compete with the global capacities of Earth to recycle the elements of life. In the coming years, we will see how the world community reacts to this challenge, and what combination of conservation, technological development, and adaptation is ultimately adopted.
Calibration of Seismograph Network may meet Test Ban Treaty's monitoring needs
Authors: Firbas Petr , Fuchs Karl , Mooney Walter D. 
Published: October 2006

Systematic calibration of a network of seismographs could meet the seismic monitoring needs of the United Nations' comprehensive nuclear test ban treaty, a feasibility study suggests. To calibrate the network, known as the International Monitoring System (IMS), the three‐dimensional seismic structure of the Earth must be taken into account. Deep seismic sounding (DSS) profiles and global three‐dimensional seismic velocity inversions play prominent roles.A verifiable test ban treaty is an important societal and technical goal. An essential ingredient is the ability to accurately locate seismic events, probably within a circle with a radius of 18 km, which is about 1000 km2. This would be for events with magnitude greater than 4 in continental areas.
Satellite monitoring of remote volcanoes improves study efforts in Alaska
Authors: Dean K. , Servilla M. , Roach A. , Foster B. , Engle K. 
Published: October 2006

Satellite monitoring of remote volcanoes is greatly benefitting the Alaska Volcano Observatory (AVO), and last year's eruption of the Okmok Volcano in the Aleutian Islands is a good case in point. The facility was able to issue and refine warnings of the eruption and related activity quickly, something that could not have been done using conventional seismic surveillance techniques, since seismometers have not been installed at these locations.AVO monitors about 100 active volcanoes in the North Pacific (NOPAC) region, but only a handful are observed by costly and logistically complex conventional means. The region is remote and vast, about 5000 × 2500 km, extending from Alaska west to the Kamchatka Peninsula in Russia (Figure 1). Warnings are transmitted to local communities and airlines that might be endangered by eruptions. More than 70,000 passenger and cargo flights fly over the region annually, and airborne volcanic ash is a threat to them. Many remote eruptions have been detected shortly after the initial magmatic activity using satellite data, and eruption clouds have been tracked across air traffic routes. Within minutes after eruptions are detected, information is relayed to government agencies, private companies, and the general public using telephone, fax, and e‐mail. Monitoring of volcanoes using satellite image data involves direct reception, real‐time monitoring, and data analysis. Two satellite data receiving stations, located at the Geophysical Institute, University of Alaska Fairbanks (UAF), are capable of receiving data from the advanced very high resolution radiometer (AVHRR) on National Oceanic and Atmospheric Administration (NOAA) polar orbiting satellites and from synthetic aperture radar (SAR) equipped satellites.
Preconceptions abound among students in an introductory earth science course
Authors: DeLaughter John E. , Stein Seth , Stein Carol A. , Bain Kenneth R. 
Published: October 2006

Although the Third International Mathematics and Science Study found that most 8th‐grade students like science and feel that they are doing well in it [Geary, 1997], fewer than one‐quarter of U.S. adults can define the term DNA and only one in 11 knows what a molecule is [Augustine, 1998]. Hence the motivated, bright young people described by the study somehow become scientific illiterates despite the best efforts of elementary, secondary, and college‐level instructors.This phenomenon has prompted various investigations into reasons why students have difficulty learning science. One possibility is illustrated by the famed video [Shapiro etal, 1988] showing that most of the graduating Harvard seniors surveyed confidently attributed the cause of the seasons to changes in the distance between the Earth and Sun rather than to the Earth's tilt. They had a clear conception of the answer, but it was wrong.
New map compiled of Europe's gravity field
Authors: Wybraniec Stanislaw , Zhou Shaohua , Thybo Hans , Forsberg Rene , Perchuc Edward , Lee Michael , Demianov Gleb D. , Strakhov V. N. 
Published: October 2006

A gravity anomaly map of Europe was recently compiled that incorporates significant new data, especially from the eastern European countries. The map (Figure 1a), which was developed by a group of geophysicists and geodesists, goes a long way toward establishing a common and reliable database.Geological information contained in the regional gravity field are highlighted in the map, and all known large‐scale geological structures are well coordinated with the anomaly patterns. The map offers basic gravity information for geophysical studies related to subsurface geology and large‐scale tectonic features in Europe and reinforces or supports previous interpretations of largescale tectonic features.
Study provides data on active plate tectonics in southeast Asia region
Authors: Wilson P. , Rais J. , Reigber Ch. , Reinhart E. , Ambrosius B. A. C. , Le Pichon X. , Kasser M. , Suharto P. , Majid Dato' Abdul , Yaakub Dato' Paduka Awang Haji Othman Bin Haji , Almeda R. , Boonphakdee C. 
Published: October 2006

A major geodynamic study has provided significant new information about the location of active plate boundaries in and around Southeast Asia, as well as deformation processes in the Sulawesi region of Indonesia and tectonic activity in the Philippine archipelago. Results also have confirmed the existence of the so‐called Sunda Block, which appears to be rotating with respect to adjacent plates.The study, known as the Geodynamics of South and South‐East Asia (GEODYSSEA) project, has been a joint venture of the European Commission and the Association of South‐ East Asian Nations. It began in 1991 and involved a large team of European and Asian scientists and technicians studying the complex geodynamic processes and natural hazards of the region from the Southeast Asia mainland to the Philippines to northern Australia. Earthquakes, volcanic eruptions, tsunamis, and tectonically induced landslides endanger the lives of millions of people in the region, and the tectonic activity behind these natural hazards results from the convergence and collision of the Eurasian, Philippine, and Indo‐Australian Plates at relative velocities of up to 10 cm per year.
Detailed look at final stage of plate break‐off is target of study in Romania
Authors: Wenzel F. , Achauer U. , Enescu D. , Kissling E. , Russo R. , Mocanu V. , Musacchio G. 
Published: October 2006

Geophysical experiments next year in Romania may provide insight into a common but short‐lived seismic process that can be observed and understood at only one spot on Earth at present. About 150 stations will be set up in the Vrancea area in the southeast Carpathian Mountains to, in effect, record the terminal phase of the detachment of a subducting slab of oceanic lithosphere. This is a major regional tomographic study using a large number of broadband seismometers, which will operate for 6 months. Images will be used for hazard assessment as well as for a delineation of detachment history.Active subduction of oceanic lithosphere at convergent plate boundaries involves earthquakes, magmatism, metamorphism, and deformation—some of the most vivid manifestations of any plate tectonic process. The initiation and termination of subduction, however, remains relatively poorly understood. When convergence of lithospheric plates ceases and the suction force of the subducting plate becomes negligible, the subducting slab moves into an almost vertical position. If subduction occurs in an arcuate geometry, the slab is likely to be segmented.
Yellow River's water and sediment discharge decreasing steadily
Authors: Yang Z. S. , Milliman J. D. , Galler J. , Liu J. P. , Sun X. G. 
Published: October 2006

The amount of water and sediment discharged by the Yellow River in northern China has been decreasing steadily over the past 20–25 years, such that in recent years it has contributed relatively little sediment to the Gulf of Bohai. This is quite at odds with the well‐known story in which the Yellow River has been regarded as a primary contributor of fluvial sediment to the global ocean.If the trend of decreasing discharge continues, the environmental and economic impacts to the Yellow River delta and adjacent coastal waters could be dramatic. Already shrimp harvest from the brackish waters of the western Gulf of Bohai has decreased markedly, and there has been considerable coastal retreat along parts of the delta.
Upcoming solar maximum could affect wide range of technologies
Authors: Showstack Randy 
Published: October 2006

“Sparky, get me headquarters!” the officer barks, as his radio operator frantically tries calling for assistance over the fading short‐wave. Bombs are falling and bullets flying. At the last minute, the call gets through in this anxious scene typical in many World War II movies.The officer and Sparky may not have known that energetic releases during Solar Cycle 17, which coincided with the war years, could have caused radio signals to fade in and out, says Gary Heckman, senior space weather forecaster with the National Oceanic and Atmospheric Administration's Space Environment Center (SEC) in Boulder, Colo.
Scientists study deep geological structure between New Hebrides Arc and Eastern Australian Margin
Authors: Lafoy Y. , Van de Beuque S. , Bernardel G. , Missegue F. , Nercessian A. , Auzende J. M. , Symonds P. A. , Exon N. F. 
Published: October 2006

French and Australian scientists hope that deep seismic profiling performed earlier this year in the southwest Pacific will improve understanding of the geological framework, crustal characteristics, and evolution of basins and ridges between the eastern Australian margin and the New Hebrides Trench system. The data already have indicated that the basements of several basins are thinned and oceanic, that the basements of several ridges are continental, and that, contrary to previous thinking, the Loyalty Basin was formed in late Cretaceous time.Submerged continental fragments separated by deep ocean basins dominate the region in the west, and the Australian Plate is subducting beneath the New Hebrides Arc in the east. Subduction started in Late Miocene time [MacFarlane et al., 1988] at a rate of 12 cm/ year with a convergence direction of WSW‐ENE [Dubois et al., 1977].
Sclerosponges may hold new keys to marine paleoclimate
Authors: Swart Peter K. , Moore Michael , Charles Chris , Böhm Florian 
Published: October 2006

The potential for using sclerosponges, marine organisms that secrete a hard calcerous skeleton, as paleoclimatic indicators has attracted the interest of a number of scientists. Sclerosponges are composed mainly of calcium carbonate and they are very long lived. Variations in their skeletal chemistry contain proxy information regarding their environment and that information has the potential to augment, if not supplant, data from scleractinian corals in interpreting past water temperature, salinity, and productivity over periods of 100s to 1000s of years.Sclerosponges, or calcified demosponges, contain aragonite or calcite and a small amount of siliceous material. Lang et al. [1975] report that these sponges grow within a reef framework, under coral talus in the shallower parts of a reef less than 55 m deep and on steep surfaces of the fore‐reef between 55 and 145 m deep. The largest and most conspicuous of the sclerosponges described by those authors is Ceratoporella nicholsoni (Figure 1), which is reported to attain a diameter in excess of 1 m. These sponges are similar in growth habit to many massive vanities of scleractinian corals, the live sponge inhabiting the upper portion of the skeleton, while the lower portion of the skeleton is essentially dead.
Offshore springs and seeps are focus of working group
Authors: Burnett Bill 
Published: October 2006

People have been curious about offshore springs and seeps since at least the days of the Romans. In spite of many centuries of both casual and serious observations, there has been relatively little scientific study concerning the magnitude and effects of groundwater flow into the sea. Rather, studies were performed mostly to address water resource issues. Investigations over the past decade or so have now shown that groundwater discharge, at least in some cases, may be important for geochemical budgets and ecological effects.The Scientific Committee on Oceanic Research (SCOR) and the Land‐Ocean Interactions in the Coastal Zone (LOICZ) Project of the International Geosphere‐Biosphere Program have recently established a working group of experts to examine questions relating specifically to groundwater discharge in the coastal zone. Direct groundwater flow into the ocean is known to occur as springs and seeps in near‐shore areas in many parts of the world. Submarine springs, for example, are well known off both coasts of Florida; Mexico's Yucatan Peninsula; in several areas around the Pacific rim including Chile, Hawaii, Guam, American Samoa, and Australia; in the Persian Gulf near Bahrain; in the Mediterranean Sea off Spain, France, Italy, Greece, Syria, Lebanon, Israel, and Libya; and in many other locations.
Magnetic helicity attracts interdisciplinary participation at Chapman Conference
Authors: Canfield Richard C. , Pevtsov Alexei A. 
Published: October 2006

During the last 5 years interest in magnetic helicity has grown dramatically in solar physics as a result of improved capabilities to measure and image magnetic fields. Magnetic helicity was introduced by K. Moffatt in the late 1950s as a topological invariant that describes the complexity of a magnetic field. The topological aspect of helicity is readily visualized in a Moebius strip, in which the system of interest is closed and helicity takes two forms, the writhing of the central axis of the strip and the twisting of the edges of the strip about that axis.In many plasmas (but not in atmospheres like that of Earth, for example), helicity is conserved, just as the sum of twist and writhe is conserved in a Moebius strip. Mathematically, it is related to linking integrals, which K. F. Gauss employed to study asteroid paths on the sky. In the late 1970s the concept of magnetic helicity was introduced in laboratory plasma physics, turbulence theory, space physics, and statistical theory.
Debating complexity in modeling
Authors: Hunt Randy , Zheng Chunmiao 
Published: October 2006

Complexity in modeling would seem to be an issue of universal importance throughout the geosciences, perhaps throughout all science, if the debate last year among groundwater modelers is any indication. During the discussion the following questions and observations made up the heart of the debate.As scientists trying to understand the natural world, how should our effort be apportioned? We know that the natural world is characterized by complex and interrelated processes. Yet do we need to explicitly incorporate these intricacies to perform the tasks we are charged with? In this era of expanding computer power and development of sophisticated preprocessors and postprocessors, are bigger machines making better models? Put another way, do we understand the natural world better now with all these advancements in our simulation ability? Today the public's patience for long‐term projects producing indeterminate results is wearing thin. This increases pressure on the investigator to use the appropriate technology efficiently. On the other hand, bringing scientific results into the legal arena opens up a new dimension to the issue: to the layperson, a tool that includes more of the complexity known to exist in the real world is expected to provide the more scientifically valid answer.
Opportunity for geophysicists to meet congressional science leaders
Authors: Kingston Margo 
Published: October 2006

Scientists will flood Capitol Hill during the fourth annual Science‐Engineering‐Technology Congressional Visits Day (CVD) on April 21–22 1999, to voice their support for federal investment in science and technology. AGU encourages members to join other geoscientists for an opening day of briefings by key administration and congressional leaders followed by a day of constituent meetings with senators, representatives, and their staff. Last year, more than 250 scientists and engineers from academia and industry attended including 15 Earth scientists.CVD provides a terrific opportunity to become part of a growing movement by scientists and engineers to remind lawmakers how indispensable the research community is to society Legislators sit up and take notice when normally reticent research scientists take a few days away from the lab and pay them a visit. It also sends a powerful message when scientists from many disciplines are seen to be working together for science in the national interest, and not just promoting their own individual pursuits. This activity smartly fits the objectives of AGU's Committee on Public Affairs to prepare and encourage AGU members to interact with their elected representatives and other decision makers as well as to increase interactions with the policy process at all levels. Previous CVD events have proven successful in part because scientists and engineers advance a simple but coherent message. Participants in this year's CVD are asked to carry two core themes: Federal investment in science and technology is important for the nation. Partnerships between government, universities, and industries mean progress, economic growth, and jobs.
Network of superconducting gravimeters benefits a number of disciplines
Authors: Crossley D. , Hinderer J. , Casula G. , Frnacis O. , Hsu H.‐T. , Imanishi Y. , Jentzsch G. , Kääriänen J. , Merriam J. , Meurers B. , Neumeyer J. , Richter B. , Shibuya K. , Sato T. , van Dam T. 
Published: October 2006

A global network of superconducting gravimeters (SGs) is compiling significant data for a range of important studies spanning a number of disciplines concerned with the Earth's gravity, tides, environment, and geodetics. Among phenomena being looked at are seismic normal modes, the Slichter triplet, tidal gravity, ocean tidal loading, core nutations, and core modes. Hydrologists and volcanologists also may benefit from SG data.The network was set up by the Global Geodynamics Project (GGP),an international program of observations of temporal variations in the Earth's gravity field. Observations began in 1997 and will continue until 2003. Eighteen SGs currently are in operation in the network (see Figures 1 and 2).