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Liu Shen Feng Caixia Fan Yan Chen Xiaoqing Yang Yuhong Zhao Huibo Coulson Ian M. 《中国地球化学学报》2020,39(6):862-886
Acta Geochimica - This work reports an important episode of extensional, mafic magmatism that impacted the North China Craton (NCC) during the Permo-Triassic and influenced the evolution of this... 相似文献
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María Luisa Ávila-Jiménez Stephen J. Coulson Torstein Solhøy & Anna Sjöblom 《Polar research》2010,29(1):127-137
There are over 500 species of arthropods recorded from Svalbard. These animals overwinter either within the soil or on the ground surface, and have to tolerate an environment where the ground is frozen for over 9 months each year. Three cold-tolerance strategies have been described from Svalbard invertebrates: freeze avoidance, freeze tolerance and desiccation. Once in a cold-tolerant state the animals can be extremely cold tolerant in terms of both minimum exposure temperature and period of exposure. How the overwintering capabilities of these animals will be affected by climate changes during the next 100 years, as predicted by climate models, is not yet known. Four principle factors with an impact on overwintering of the terrestrial arthropod fauna are outlined here: (1) warmer winter temperatures, with an increased frequency of extreme events such as freeze–thaw cycles and surface icing; (2) changes in snow fall and snow lie; (3) pollutant load; and (4) dispersal of invertebrates to Svalbard. Finally, areas where further research is required are highlighted: including the development of controlled multi-season field experiments; effect of freeze–thaw cycles; changes in thickness and distribution of snow lie, with the subsequent effects on duration of the summer period; chill susceptibility of soil arthropods; assessing potential colonizing species and the likelihood of these species becoming established; assessing the effect of gene flow from surrounding populations; interactions between pollution and cold tolerance; anoxia stress; and the genetics of cold tolerance. 相似文献
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Martin Coulson 《GeoJournal》1995,36(4):371-382
Greater access to information after the Post-Cold War period gives researchers new opportunities to study the environmental, economic and social impacts of military defence. Changing political and economic circumstances are influencing the distribution of military facilities and defence industries in developed countries. The paper illustrates these developments and looks at the contribution to change made by pressure groups end at examples from the UK defence sector. Defence forces are reacting to criticism about negative impacts through a variety of measures including environmental training, site remediation and the use of simulation technology. A framework for further research is presented and many references cited. 相似文献
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S.G. Coulson 《Astrophysics and Space Science》2003,283(2):279-285
During the Leonid meteor shower of November 1999 a very bright meteor train, subsequently called the Y2K meteor, was observed.
Analysis of the trajectory of the meteor suggests that it was composed of two distinct materials. The bulk of the meteor was
composed of a comet-like material, while a much smaller fraction was of a denser carbonaceous material. A simple model is
used to analytically determine the mass of the meteor fragments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Summary Zippa Mountain pluton is a Mesozoic concentrically-zoned intrusion, located within the Canadian Cordillera of British Columbia.
An extensive phase of K-feldspar bearing syenite grades towards its margins to mela-syenite and clinopyroxenite. This simple
pattern of petrological zonation is overprinted by localised occurrences of silica-undersaturated, peralkaline rock types.
High-purity wollastonite skarns occur within and peripheral to the intrusion and result from extensive interaction between
intrusion-related fluids and Permian limestone/marble, at shallow crustal levels. Field, chemical and isotopic studies provide
insights into interaction between a parental syenitic magma and these country rocks. To achieve this, petrological studies
of four of the skarn bodies present have been combined with chemical and isotopic data from the pluton, and from drill core
through the skarn into the pluton, to reconstruct the stages in the development of wollastonite skarn and progressive magma-country
rock interaction. Derivation of peralkaline compositions from the syenitic magma requires either a loss of Si and Al, or addition
of Na and/or K. Our studies preclude the addition of alkali elements but highlight extensive Si-infiltration into the limestone,
while the conversion of marble to grossular-andradite skarn, indicates Al-infiltration. Fluid egress resulted in de-silicification/de-alumination
of the Zippa Mountain magmas, and increased peralkalinity; wollastonite and garnet-bearing skarn formed as a by-product. Hence,
the development of peralkaline rock compositions at Zippa Mountain required a parental syenitic magma, and reaction and/or
interaction with calcareous country rocks.
Present address: Institut für Geowissenschaften, Universit?t Tübingen, Tübingen, Germany 相似文献
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Ian M. Coulson Mike E. Villeneuve Gregory M. Dipple Robert A. Duncan James K. Russell James K. Mortensen 《Journal of Volcanology and Geothermal Research》2002,114(3-4)
Knowledge of the time-scales of emplacement and thermal history during assembly of composite felsic plutons in the shallow crust are critical to deciphering the processes of crustal growth and magma chamber development. Detailed petrological and chemical study of the mid-Cretaceous, composite Emerald Lake pluton, from the northern Canadian Cordillera, Yukon Territory, coupled with U–Pb and 40Ar/39Ar geochronology, indicates that this pluton was intruded as a series of magmatic pulses. Intrusion of these pulses produced a strong petrological zonation from augite syenite, hornblende quartz syenite and monzonite, to biotite granite. Our data further indicate that multiple phases were emplaced and cooled to below the mineral closure temperatures over a time-scale on the order of the resolution of the 40Ar/39Ar technique (1 Myr), and that emplacement occurred at 94.3 Ma. Simple thermal modelling and heat conduction calculations were used to further constrain the temporal relationships within the intrusion. These calculations are consistent with the geochronology and show that emplacement and cooling were complete in less than 100 kyr and probably 70±5 kyr. These results demonstrate that production, transport and emplacement of the different phases of the Emerald Lake pluton occurred essentially simultaneously, and that these processes must also have been closely related in time and space. By analogy, these results provide insights into the assembly and petrogenesis of other complex intrusions and ultimately lead to an understanding of the processes involved in crustal development. 相似文献