Foliose Dictyoceratida of the Australian Great Barrier Reef     

Clive R.  Wilkinson 《Marine Ecology》1988,9(4):321-327

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Marine scientific research in offshore areas : Ireland and the law of the sea convention     

Clive R. Symmons  Piers R. R. Gardiner 《Marine Policy》1983,7(4):291-301

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Volcanology of Erebus volcano,Antarctica     

Clive Oppenheimer  Philip Kyle 《Journal of Volcanology and Geothermal Research》2008

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Activities and demographic trends in UK astronomy     

Clive N Tadhunter 《Astronomy& Geophysics》2000,41(2):2.19-2.22

The 1998 Demographic Trends Survey represents a snapshot of the astronomical community as it was in February 1998. On the positive side, there was a modest increase in the number of permanent academics in university positions over the five years covered by the survey. However, the survey also highlights several areas of concern. These include: the tension between the expansion in the university research groups on the one hand, and the decrease in PPARC funding for central facilities and grants on the other; the significant fall in the numbers of permanent technical staff in the universities; the lack of women in permanent and senior positions in UK astronomy; and the overall poor job prospects in astronomy for recent PhD students and postdocs.
Clive Tadhunter reports on the state of astronomy in the UK.  相似文献   

Shallow magma transport for the 2002–3 Mt. Etna eruption inferred from thermal infrared surveys     

Letizia Spampinato  Sonia Calvari  Clive Oppenheimer  Luigi Lodato 《Journal of Volcanology and Geothermal Research》2008

The 26 October 2002–28 January 2003 eruption of Mt. Etna volcano was characterised by lava effusion and by an uncommon explosivity along a 1 km-long-eruptive fissure on the southern, upper flank of the volcano. The intense activity promoted rapid growth of cinder cones and several effusive vents. Analysis of thermal images, recorded throughout the eruption, allowed investigation of the distribution of vents along the eruptive fissure, and of the nature of explosive activity. The spatial and temporal distribution of active vents revealed phases of dike intrusion, expansion, geometric stabilization and drainage. These phases were characterised by different styles of explosive activity, with a gradual transition from fire fountaining through transitional phases to mild strombolian activity, and ending with non-explosive lava effusion. Here we interpret the mechanisms of the dike emplacement and the eruptive dynamics, according to changes in the eruptive style, vent morphology and apparent temperature variations at vents, detected through thermal imaging. This is the first time that dike emplacement and eruptive activity have been tracked using a handheld thermal camera and we believe that its use was crucial to gain a detailed understanding of the eruptive event.  相似文献   

Coastal resource degradation in the tropics: does the tragedy of the commons apply for coral reefs, mangrove forests and seagrass beds     

Wilkinson C  Salvat B 《Marine pollution bulletin》2012,64(6):1096-1105

The keynote paper by Garrett Hardin 44 years ago introduced the term 'tragedy of the commons' into our language (Hardin, 1968); this term is now used widely, but it is neither universally accepted nor fully understood. Irrespective, the 'tragedy of the commons' is an increasing reality for more than 500 million people that rely on the biodiversity resources and services of tropical coral reefs, mangrove forests, seagrass beds and associated fisheries. These natural resources continue to decline despite major advances in our scientific understanding of how ecosystems and human populations interact, and the application of considerable conservation and management efforts at scales from local user communities to oceans. Greater effort will be required to avert increasing damage from over-exploitation, pollution and global climate change; all deriving from increasing exploitation driven by poverty and progress i.e. continuing to expand development indefinitely and extraction of resources at industrial scales. However, the 'tragedy' concept has been widely criticized as a simple metaphor for a much larger set of problems and solutions. We argue that the 'tragedy' is essentially real and will continue to threaten the lives of millions of people unless there are some major moral and policy shifts to reverse increasing damage to coastal habitats and resources. We agree with the conclusion by Hardin that the solution to the tragedy will not be through the application of natural sciences, but via implementing exceedingly difficult and controversial moral decisions. An extreme example of a moral and controversial direction suggested by Hardin was in re-examining the 'freedom to breed' as an inherent human value. The need for 'moral decisions' is even greater in 2012.  相似文献   

Disputed South China Sea hydrocarbons in perspective   总被引：1，自引：0，他引：1  

Nick A. Owen  Clive H. Schofield 《Marine Policy》2012,36(3):809-822

Maritime and territorial disputes have been a source of tension among the states bordering the South China Sea for decades. These disputes are often framed as being at least partially driven by the desire to gain access to much needed seabed hydrocarbon resources. Suggestions that major oil and gas riches are at stake in the South China Sea have arguably encouraged States to be inflexible in their claims and negatively impacted on bilateral relations. Indeed, controversial incidents relating to hydrocarbon exploration have occurred on multiple occasions, and as recently as mid-2011.This paper critically examines the South China Sea ‘hydrocarbon factor’. The wide range of estimates that circulate in the public domain are discussed in detail. Using a hypothetical and optimistic estimate of disputed oil and gas reserves based on the best possible interpretation of available data, depletion and production curve analysis is applied to determine the production profile of disputed reserves, and an evaluation of their potential benefit to energy security for each country with claims in the South China Sea is made. Analysis shows that constraints on production mean that disputed South China Sea oil and gas may only constitute a small part of the solution to Southeast Asia's growing energy security challenges, and does not have the capacity to reverse the trend of growing reliance on imports to the region. Escalating demand for imported hydrocarbons would instead reinforce the importance of sea-lane security to regional energy security.  相似文献   

The crater lake and hydrothermal system of Mount Pinatubo,Philippines: evolution in the decade after eruption     

James?A.?StimacEmail author  Fraser?Goff  Dale?Counce  Adrienne?C.?L.?Larocque  David?R.?Hilton  Uwe?Morgenstern 《Bulletin of Volcanology》2004,66(2):149-167

The June 1991 eruption of Mount Pinatubo, Philippines breached a significant, pre-eruptive magmatic-hydrothermal system consisting of a hot (>300 °C) core at two-phase conditions and surrounding, cooler (<260 °C) liquid outflows to the N and S. The eruption created a large, closed crater that accumulated hydrothermal upwellings, near-surface aquifer and meteoric inflows. A shallow lake formed by early September 1991, and showed a long-term increase in level of ~1 m/month until an artificial drainage was created in September 2001. Comparison of the temporal trends in lake chemistry to pre- and post-eruptive springs distinguishes processes important in lake evolution. The lake was initially near-neutral pH and dominated by meteoric influx and Cl–SO₄ and Cl–HCO₃ hydrothermal waters, with peaks in SO₄ and Ca concentrations resulting from leaching of anhydrite and aerosol-laden tephra. Magmatic discharge, acidity (pH~2) and rock dissolution peaked in late 1992, during and immediately after eruption of a lava dome on the crater floor. Since cessation of dome growth, trends in lake pH (increase from 3 to 5.5), temperature (decline from 40 to 26 °C), and chemical and isotopic composition indicate that magmatic degassing and rock dissolution have declined significantly relative to the input of meteoric water and immature hydrothermal brine. Higher concentrations of Cl, Na, K, Li and B, and lower concentrations of Mg, Ca, Fe, SO₄ and F up to 1999 highlight the importance of a dilute hydrothermal contribution, as do stable-isotope and tritium compositions of the various fluids. However, samples taken since that time indicate further dilution and steeper trends of increasing pH and declining temperature. Present gas and brine compositions from crater fumaroles and hot springs indicate boiling of an immature Cl–SO₄ geothermal fluid of near-neutral pH at approximately 200 °C, rather than direct discharge from magma. It appears that remnants of the pre-eruptive hydrothermal system invaded the magma conduit shortly after the end of dome emplacement, blocking the direct degassing path. This, along with the large catchment area (~5 km²) and the high precipitation rate of the area, led to a rapid transition from a small and hot acid lake to a large lake with near-ambient temperature and pH. This behavior contrasts with that of peak-activity lakes that have more sustained volcanic gas influx (e.g., Kawah Ijen, Indonesia; Poas and Rincón de la Vieja, Costa Rica).Editorial responsibility: H. Shinohara  相似文献   

The Iberian Pyrite Belt: a mineralized system dismembered by voluminous high-level sills     

Clive A. Boulter  Carles Soriano  & Pascale Zimman 《地学学报》2001,13(2):99-103

The Iberian Pyrite Belt is a world-ranking massive sulphide province in which a reassessment of the palaeovolcanology has dramatically changed understanding of the source of metals and mechanism of ore formation. In the northern sector, the deposits are hosted by a sill–sediment complex in which more than 90% of the sills post-date the sulphide sheets. Because of a very high sill/sediment ratio, these late intrusions dominate the host succession and have severely disrupted the post-mineralization configuration thus obscuring the true genetic relationships. For example, some oxide deposits have been separated by hectometric sills from sulphide deposits they originally capped, creating seemingly totally independent mineralizing systems. In addition, stratiform sulphide sheets without underlying stockworks are not necessarily allochthonous. An early timing for the mineralization with respect to volcanism means that metals had to be predominantly sourced from the sedimentary basin and the continental crust below the volcanogenic sequence.  相似文献   

Regolith-atmosphere exchange of water and carbon dioxide on Mars: Effects on atmospheric history and climate change     

Fraser P. Fanale  Bruce M. Jakosky 《Planetary and Space Science》1982,30(8):819-831

Exchange of CO₂ and H₂O between the Mars regolith and the atmosphere-cap system plays an important role in governing the evolution of the martian atmosphere and the martian climate. Most of the exchangeable CO₂ (perhaps one or two orders of magnitude more than the atmospheric inventory) is currently adsorbed on the deep regolith, and can be “cryopumped” to a large quasipermanent CO₂ cap (not now present) during lowest Mars obliquity (θ). During the obliquity driven regolith-cap CO₂ exchange cycle, the atmospheric pressure varies harmonically between ~0.1 mb (lowest Θ) and ? 20 mb (highest Θ). The regolith buffer plays only a small or negligible role in the seasonal CO₂ pressure variations caused by atmosphere-cap exchange because adsorption greatly inhibits diffusion of the seasonal “pressure wave” into the regolith. In contrast, thermally driven H₂O seasonal exchange between the atmosphere and regolith appears to be in large part responsible for observed seasonal variations in the small atmospheric H₂O inventory. Long term exchange of H₂O may be dominated by transfer between the polar caps and ice in the regolith. Available and potential tests of regolith-atmospheric-cap volatile exchange models using ground-based and spacecraft-based techniques are discussed.  相似文献