Earth System Science: an oxymoron?     

Nick Clifford  Keith Richards 《地球表面变化过程与地形》2005,30(3):379-383

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Granites are not diapiric!     

Nick Petford  & John D. Clemens 《Geology Today》2000,16(5):180-184

How are granite magmas transported from their source regions in the deep crust, through 10–40 km of overlying solid rock and emplaced close to the Earth's surface? What are the mechanical processes that allow this to take place and how long does it all take? These problems have challenged and preoccupied geologists since the days of Hutton. In the ensuing 200 years or so, a range of ideas from the plausible to the eccentric have been put forward to explain the granite phenomenon. As a result of developments in our understanding of the physical behaviour of granitic magmas and their host rocks over the last decade, we are now in a position to begin to offer some more informed and realistic models of the processes involved.  相似文献   

The effect of non-gravitational forces on the median inclination of short-period comets     

David W. Hughes  P. Nick Sleep  Barrie W. Jones  J. Michael Jones 《Monthly notices of the Royal Astronomical Society》2007,382(4):1675-1689

The numbered Jupiter family comets (orbital periods   P < 20 yr  ) have a median orbital inclination of about     . In this paper, we integrate the orbits of these comets into the future, under the influence of both typical non-gravitational forces and planetary perturbation, using a Bulirsch–Stoer integrator. In the case where non-gravitational forces were not acting, the median inclination of those comets that remained on   P < 20 yr  orbits increased at the rate of  (1.92 ± 0.12) × 10⁻³ deg yr⁻¹  for the first 3600 yr of the integration. During this time the population of the original family decreases, such that the half-life is about 13 200 ± 800 yr. The introduction of non-gravitational forces slows down the rate of increase in inclination to a value of around  (1.23 ± 0.16) × 10⁻³ deg yr⁻¹  . This rate of increase in inclination was found to be only weakly dependent on the non-gravitational parameters used during the integration. After a few thousand years, the rate of change in inclination decreases, and after 20 000 yr the inclinations of those initial Jupiter family members that still have orbits with   P < 20 yr  become constant at about     , independent of whether non-gravitational forces are acting or not. The presently known Jupiter family of comets is losing members at the rate of one in every 67 yr. To maintain the family in equilibrium, Jupiter has to capture comets at a similar rate, and these captured comets have to be of low inclination to compensate for the pumping up of inclinations by gravitational perturbation.  相似文献   

Reconstituting natures: Articulating other modes of living together     

Nick Bingham 《Geoforum》2008,39(1):83-87

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Collective responsibility amplifies mitigation behaviors     

Nick Obradovich  Scott M. Guenther 《Climatic change》2016,137(1-2):307-319

How can individuals be convinced to act on climate change? It is widely assumed that emphasizing personal responsibility for climate change is effective at increasing pro-climate behavior whereas collectively framing the causes of climate change diffuses responsibility and dampens the incentive for individual action. We observe the opposite result. Here we find, across three experiments, that emphasizing collective responsibility for the causes of climate change increases pro-climate monetary donations by approximately 7 % in environmental group members and by 50 % in the general public. Further, highlighting collective responsibility amplifies intent to reduce future carbon emissions. In contrast, focusing on personal responsibility for climate change does not significantly alter donations to climate change advocacy or the intent for future pro-climate behavior. These effects replicate and persist multiple days after treatment.  相似文献   

Formation of orthopyroxenite by reaction between peridotite and hydrous basaltic melt: an experimental study     

Chunguang Wang  Yan Liang  Nick Dygert  Wenliang Xu 《Contributions to Mineralogy and Petrology》2016,171(8-9):77

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Association of gold with uraninite and pyrobitumen in the metavolcanic rock hosted hydrothermal Au-U mineralisation at Rompas,Peräpohja Schist Belt,northern Finland     

Ferenc Molnár  Harry Oduro  Nick D. J. Cook  Esa Pohjolainen  Ágnes Takács  Hugh O’Brien  Lassi Pakkanen  Bo Johanson  Richard Wirth 《Mineralium Deposita》2016,51(5):681-702

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A qualitative risk assessment for the impacts of climate change on nationally and internationally important geoheritage sites in Scotland     

Rachel M.L. Wignall  John E. Gordon  Vanessa Brazier  Colin C.J. MacFadyen  Nick S. Everett 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):120-134

Climate change is a significant concern for nature conservation in the 21?st century. One of the goals of the 2014 Scottish Climate Change Adaptation Programme is to identify the consequences of climate change for protected areas and to put in place adaptation or mitigation measures. As a contribution to the process, this paper develops a methodology to identify the relative level of risk to nationally and internationally important geological and geomorphological sites in Scotland from the impacts of climate change. The methodology is based on existing understanding of the likely responses of different types of geosite to specific aspects of climate change, such as changes in rainfall, rising sea levels or increased storminess, and is applied to assess the likelihood of damaging impacts on groups of similar geoheritage features in sites with similar characteristics. The results indicate that 80 (8.8%) of the ～900 nationally and internationally important geoheritage sites in Scotland are at ‘high’ risk from climate change. These include active soft-sediment coastal and fluvial features, finite Quaternary sediment exposures and landforms in coastal and river locations, active periglacial features, sites with palaeoenvironmental records, finite or restricted rock exposures and fossils. Using this risk-based assessment, development of indicative geoheritage climate-change actions have been prioritised for these sites. Depending on the characteristics of the sites, management options may range from ‘do nothing’ to rescue excavations and posterity recording. Monitoring is an essential part of the management process to trigger evidence-based interventions.  相似文献   

Rangeland management and climate hazards in drylands: dust storms,desertification and the overgrazing debate     

Nick Middleton 《Natural Hazards》2018,92(1):57-70

This paper examines the theory and supporting evidence for links between desertification, drought and dust storms with a particular focus on studies undertaken in and around the Gobi Desert. Overgrazing of rangeland by pastoralists has been the most commonly cited cause of desertification in global drylands for more than 30 years, but the evidence supporting this link is not always convincing. Nonetheless, overgrazing, desertification and dust storms are frequently connected, regardless. Drought is another well-known and important driver of vegetation cover change. Distinguishing between vegetation cover adversely affected by drought and that reduced by grazing is imperative for policy makers because identifying the incorrect driver of vegetation change risks the development of inappropriate policy.  相似文献   

Lid tectonics-Preface     

Craig O'Neill  Nick M.W.Roberts 《地学前缘(英文版)》2018,9(1):1-2

正The idea that plate tectonics may not have operated deep in Earth's Precambrian past has a long legacy.What predated plate tectonics is unknown,and advances in data-from geochemical,geological and tectonic,to paleomagnetic,as well as modelling ap-  相似文献