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Abstract

Kagan (2002) argues that the different responses of Europeans and Americans to major strategic and international challenges is not simply due to differences in the current administrations, but rather results from (i) a power gap and (ii) differing ideologies. This article applies Kagan's theory to climate policy, employing terrorism policy as a point of comparison. We argue that the power gap between Europe and America is unable to explain the differences in climate policy. In contrast, the ideology gap may indeed have some explanatory value. Furthermore, we argue that one additional feature is critical—the costs and benefits imposed by climate change and terrorism prevention, and the process by which such costs and benefits are evaluated, differ between America and Europe.  相似文献   
375.
The ophiolites of Othris, northern Greece, and Troodos, Cyprus, are of mixed lherzolite-harzburgite and harzburgite sub-type respectively. Within both ophiolites an entire spectrum of harzburgite, plagioclase harzburgite, lherzolite and plagioclase lherzolite interpreted respectively as residual and highly, moderately and slightly modified upper mantle has been recognised. Plagioclase lherzolite frequently contains gabbroic segregations generated by partial melting and incomplete extraction. Othris shows the full range of mantle peridotites while Troodos is dominated by harzburgite with very minor occurrences of plagioclase harzburgite and lherzolite. Chemically, the plagioclase lherzolites have low contents of the basaltophillic minor elements, and a composition slightly more residual than postulated upper mantle compositions, suggestive of a preceding phase of minor depletion. The Othris and Troodos ophiolites seem to have formed under fundamentally different environments — Othris as a marginal ophiolite at the inception on rifting of continental crust, and Troodos later in such an event when spreading was well established.  相似文献   
376.
Petrology and origin of primitive lavas from the Troodos ophiolite,Cyprus   总被引:13,自引:0,他引:13  
Parental magmas to the Troodos ophiolite are characterised by low TiO2 and Al2O3 and high SiO2. Extremely fresh and chemically primitive (high MgO) rocks are found within the Upper Pillow Lavas and along the Arakapas Fault Belt of Cyprus and contain forsteritic olivine±enstatite and groundmass clinopyroxene set in glass or plagioclase, with accessory magnesiochromite and sometimes hornblende. They are quartz-normative and may have originally contained up to 3 wt% H2O. Geochemically, there are three distinct groups of primitive lavas, based on TiO2 and Zr contents but also reflected by CaO, Na2O and REE abundances. These groups cannot be related by crystal fractionation and are considered to have been generated by incremental melting of a variably depleted source region. The parental magma to the least depleted group (Group I) was that of the major portion of the Troodos plutonic complex and is similar to those postulated for other low-Ti ophiolites. Chemically it has close affinities with komatiitic basalts. The most depleted lavas (Group III) all have U-shaped REE profiles and variable 143Nd/ 144Nd ratios, interpreted in terms of metasomatism of the source region by an incompatible element-enriched component which was probably derived from a subducted slab. These lavas represent an intermediate step in the development of boninite series rocks.  相似文献   
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