“国际地球年”进展

人类生存与发展的基本关系是人与自然的关系,社会可持续发展的基础是自然支撑系统。因此,人类社会必须对赖以生存的地球深入完整地了解并合理地使用。然而,在经历了近300多年科学技术发展所带来的工业革命之后,人类社会才逐步意识到地球所能供给的自然资源正出现危机,我们赖以生存的环境正受到人为作用越发严重的破坏,随着社会财富的快速增长与聚集,自然灾害所造成的损失也越来越大。[第一段]     

The Natural Hazards Theme of the International Year of Planet Earth

The United Nations has declared 2008 to be the International Year of Planet Earth. It is being organised under the auspices of the International Union of Geological Sciences and UNESCO. Planning for the International Year of Planet Earth has consisted of establishing 10 major science themes including Hazards. The Hazards Theme is centred around the following key questions: (1) How have humans altered the geosphere, the biosphere and the landscape, thereby creating long-term changes detrimental to life and the environment and triggering certain hazards, while increasing societal vulnerability to geophysical (geological and hydrometeorological) hazards? (2) What technologies and methodologies are required to assess the vulnerability of people and places to hazards and how might these be used at a variety of spatial scales? (3) How do geophysical hazards compare relative to each other regarding current capabilities for monitoring, prediction and mitigation and what can be done in the short-term to improve these capabilities (4) What barriers exist to the utilisation of risk and vulnerability information by governments (and other entities) for risk and vulnerability reduction policies and planning (including mitigation) from each of the geophysical hazards? Following the 26 December 2004 Indian Ocean Tsunami and the UN World Conference on Disaster Reduction held in Kobe, Japan in January 2005, the International Council for Science (ICSU) decided to establish a major research programme and initiative on Natural and Human Induced Environmental Hazards and Disasters that will co-operate with the Hazards theme of the International Year and continue through to 2011.     

Structural setting, hydrothermal alteration, and gold mineralisation at the Archaean syenite-hosted Jupiter deposit, Yilgarn Craton, Western Australia

The Jupiter gold deposit in the northeastern Eastern Goldfields Province of the Yilgarn Craton of Western Australia is hosted in greenschist facies metamorphosed tholeiitic basalt, quartz–alkali-feldspar syenite, and quartz–feldspar porphyry. Syenite intrudes basalt as irregularly shaped dykes which radiate from a larger stock, whereas at least three E–W and NE–SW striking quartz–feldspar porphyries intrude both syenite and basalt. Brittle–ductile shear zones are shallow-dipping, NW to NE striking, or are steep-dipping to the south and west. Quartz ± carbonate veins that host gold at Jupiter occur in all lithologies and are divided into: (1) veins that are restricted to the shear zones, (2) discrete veins that are subparallel to shear zone-hosted veins, and (3) stockwork veins that form a network of randomly oriented microfractures in syenite wallrock proximal to shallow-dipping shear zones. The gold-bearing veins comprise mainly quartz, calcite, ankerite, and albite, with minor sericite, pyrite, chalcopyrite, galena, sphalerite, molybdenite, telluride minerals, and gold. Proximal hydrothermal alteration zones to the mineralised veins comprise quartz, calcite, ankerite, albite, and sericite. High gold grades (>2 g/t Au) occur mainly in syenite and in the hanging walls to shallow-dipping shear zones in syenite where there is a greater density of mineralised stockwork veins. The Jupiter deposit has structural and hydrothermal alteration styles that are similar to both granitoid-hosted, but post-magmatic Archaean lode-gold deposits in the Yilgarn Craton and intrusion-related, syn-magmatic, syenite-hosted gold deposits in the Superior Province of Canada. Based on field observations and petrologic data, the Jupiter deposit is considered to be a post-magmatic Archaean lode-gold deposit rather than a syn-intrusion deposit. Received: 5 January 1999 / Accepted: 24 December 1999     

Formation of Stellar Streams Due to the Decay of Star Clusters,OB Associations,and Galaxy Satellites

Astronomy Reports - This paper presents a scenario of the evolution of OB associations and star clusters from formation to decay, in the process of which they turn into stellar streams moving in...     

地质遗产、地质公园及通过2008国际地球年促进地球科学

In the years 2000 and 2001 a few visionaries in IUGS under the lead of Ed de Mulder, at that time President of IUGS, started to think out loudly about an ＂ International Year of Planet Earth＂ （YEAR）. It was their feeling that globally the geosciences did not get that part of public recognition that geosciences should earn, compared to ecology, economy, sustainable development and environmental sciences at large.[第一段]     

Chemical differentiation of the Galilean satellites of Jupiter: 4. Isochemical models for the compositions of Io, Europa, and Ganymede

Models for the composition and structure of the Galilean satellites of Jupiter (Io, Europa, and Ganymede) were constructed using geophysical data provided by the Galileo mission on the mass, average density, and moment of inertia, as well as thermodynamic data on the equation of the state of water, high-pressure ices, and meteoritic materials. The distribution of density, pressure, temperature, and gravity acceleration in the interiors of the satellites was determined. A simulation of the internal structure of the satellites showed the possibility of identical bulk compositions for water-free Io and the rock-iron cores of Europa and Ganymede (i.e., satellites without their outer ice-water shells). The sizes of the satellites’ cores (Fe with 10 wt % S) and the thicknesses of the ice-water shells of Europa (120 km) and Ganymede (900 km) were also estimated. These satellites contain 7 and 47% H₂O, respectively. The radii of Fe-10% S cores are 737 km for Io, 695 km for Ganymede, and 576 km for Europa. The ratios of the radii and masses of the Fe-S scores and rock-iron cores of Io, Ganymede, and Europa are almost identical and equal R(Fe-10%S core)/R _Cor = 0.4 and M(Fe-10% S core)/M _Cor = 10.55 ± 0.3 wt %. It was shown that the geochemical parameters of the rock-iron constituent of the satellites are similar to the material of L/LL chondrites. The silicate fraction of the satellites contains about 16 wt % FeO and shows an Fe/Si mass ratio of 0.53. The total iron to silicon mass ratio is also identical in the three satellites: (Fe_tot/Si)_Cor = 0.99 ± 0.02. This value is different from that in the bulk compositions of the most oxidized carbonaceous chondrites and the most reduced H chondrites. Io, Europa, and Ganymede could be formed in the accretion disk of Jupiter from a material similar to L/LL chondrites under relatively low temperatures, not higher than the evaporation temperature of Fe and Fe-Mg silicates.     

Inspiring the next generation of scientists with their observations of quasars,black holes,Jupiter, and SETI with the Goldstone Apple Valley Radio Telescope,GAVRT

This paper describes a radio astronomy programfor schools, the Goldstone-AppleValley Radio Telescope,GAVRT. The GAVRT program is designed to bring the inspiration and enthusiasm to a younger generation of teachers and children who learn about science by doing real science, just as Iosif Shklovsky brought to an older generation.     

国际地球年中国行动启动仪式暨纪念第39个世界地球日宣传活动在北京举行

2008年4月22日,国际地球年中国行动启动仪式暨纪念第39个世界地球日宣传活动在中国地质大学(北京)举行。“认识地球,和谐发展”为中国第39个世界地球日与国际地球年中国行动共同采用的主题,目的在于提升公众对地球的认知程度,推动地学为社会经济可持续发展服务。纪念活动由国际     

Influence of photoelectrons on the structure and dynamics of the upper atmosphere of a hot Jupiter

A self-consistent, aeronomic model of the upper atmosphere of a “hot Jupiter” including reactions involving suprathermal photoelectrons is presented. This model is used to compute the height profiles of the gas density, velocity, and temperature in the atmosphere of the exoplanet HD 209458b. It is shown that including suprathermal electrons when computing the heating and cooling functions reduces the mass loss rate of the atmosphere by a factor of five.     

Satellites and the New War on Infection: Tracking Ebola in West Africa

Satellite technologies are increasingly being deployed to manage infectious disease outbreaks. Although there is a substantive literature concerned with the geopolitics of space and the ethical issues raised by the use of remote sensing in warfare and counterinsurgency, little study has been made of the critical role played by satellites in public health crises. In this paper, we focus on the 2014–2015 Ebola virus disease (EVD) epidemic in West Africa, which saw the widespread use of public and commercial satellite-derived data, to investigate how overhead orbital and close-up viewpoints enabled by satellites are shaping attitudes to disease and determining responses to infectious threats. We argue that high-resolution satellite imagery is acting as a spur to a new spatio-temporal targeting of disease that parallels the ever more vertical dimension of contemporary warfare. At the same time, this new visualization of disease is promoting a broader ecological perspective on pathogen emergence. How can these divergent perspectives be reconciled? In addressing this question, we analyze the different uses to which satellite imagery has been put in tracking and mapping Ebola ‘hotspots’ across Guinea, Liberia, and Sierra Leone. We also consider the institutional contexts that have enabled the acquisition of this imagery. Given the rapid integration of space technologies in epidemiology and health logistics, there is now a need to examine how and with what consequences remote-sensing and communication technologies may be reconfiguring the practices and scope of global health.