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11.
《Marine Policy》2013
The tropical rocklobster fishery in the Torres Strait, based on the species Panulirus ornatus, is currently managed by input controls. The Australian Commonwealth government’s aim is to transition to a quota management system (QMS) for this fishery. The fishery is complex in terms of international boundaries, multiple jurisdictions and management objectives regulating a mix of commercial and traditional indigenous fishers and a commercial non-indigenous sector. One key objective is to promote indigenous fisher participation to meet their aspirations of achieving a greater control of the region’s fisheries resources. A Bayesian Network analysis has been applied that considers the variability in participation of indigenous fishers under key economic and socio-cultural drivers, such as the availability of a government employment program, lobster prices, social capital and capacity, and infrastructure availability. The model identifies three distinct indigenous fisher groups: full-time, active part-time, and casual lobster fishers. Scenario analyses suggest that changes in the government employment program will have a substantial impact on the relative proportion of fishers in these groups. Similarly, changes in the provision of logistics, infrastructure, and building social capital and capacity are expected to have a significant impact on the occurrence of full-time fishing. As the Commonwealth has an obligation under the Torres Strait Treaty to protect the traditional way of life and livelihood of Islanders as well as promoting employment opportunities for Traditional Inhabitants, it is important that management authorities consider both the effect of management changes for the fishery as a whole and for each indigenous fisher group separately. 相似文献
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As one of the widely used upgrading way in road engineering, the widening embankment(WE) has suffered evident differential deformation, which is even severer for highway in permafrost regions due to the temperature sensitivity of frozen soil and the heat absorption effect of the asphalt pavement. Given this issue, a full-scale experimental highway of WE was performed along the Qinghai-Tibet Highway(QTH) to investigate the differential deformation features and its developing law. The continuous three years' monitoring data taken from the experimental site, including the ground temperature and the layered deformation of WE and original embankment(OE), were used to analyze the thermal-deformation process. The results indicate that the widening part presented the remarkable thermal disturbance to the existing embankment(EE). The underlying permafrost was in a noteworthy degradation state, embodying the apparent decrease of the permafrost table and the increase of the ground temperature. Correspondingly, the heat disruption induced by widening led to a much higher deformation at the widening side compared to the original embankment, showing a periodic stepwise curve. Specifically, the deformation mainly occurred in the junction of the EE and the widening part, most of which was caused by the thawing consolidation near the original permafrost table. In contrast, the deformation of EE mainly attributed to the compression of the active layer. Furthermore, it was the deformation origination differences that resulted in the differential deformation of WE developed gradually during the monitoring period, the maximum of which reached up to 64 mm. 相似文献
13.
《Precambrian Research》2006,144(3-4):199-212
LA-ICP-MS U–Pb zircon dating and cathodoluminescene (CL) image analysis were carried out to determine the protolith and metamorphic ages of high-grade Al-rich gneisses, named as “khondalites”, from the Jining Complex of the North China Craton (NCC). The analytical results of more than 200 detrital zircon grains from the khondalites show three main age populations: 2060 Ma, 1940 Ma and 1890 Ma. These data indicate that the provenance of the Jining khondalites is Paleoproterozoic in age, but not Archean as previously suggested, and the sediments were derived from a provenance different from the Eastern Block and the Yinshan Terrane of the NCC. The nearly concordant youngest age of 1842 ± 16 Ma (207Pb/206Pb age) for the detrital zircons is interpreted as the maximum depositional age of the khondalites. Overgrowth rims of detrital zircons yield an age of 1811 ± 23 Ma, which we interpret as the metamorphic age. The new age data are consistent with the recent three-fold tectonic subdivision of the NCC and support that the Eastern and Western Blocks collided at ∼1.8 Ga to form the coherent NCC. 相似文献
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F. L. Sutherland P. C. Piilonen Khin Zaw S. Meffre J. Thompson 《Australian Journal of Earth Sciences》2013,60(6):761-773
Subordinate sapphire accompanies prevalent zircon megacrysts in the Bo Loei basaltic gem field, Ratanakiri Province, Cambodia. These deposits are important for heat-treated gem zircon. Dark blue sapphire, with rare blue-green, orange-brown and yellow stones, up to a few cm in size, include hexagonal-shaped and growth-zoned crystals. Analyses of the sapphires (electron microprobe and laser ablation-inductively coupled plasma-mass spectrometry) showed Fe as the main chromophore (0.6–2.7 wt%), with minor Ti (<0.7 wt%). Sapphire cores show enrichment in Fe relative to rims and some include exotic heavy elements (Nb up to 56, Ta up to 144, Sn up to 5 ppm). The sapphires show high Ga values (271–724 ppm) and Ga/Mg ratios (4.8–77.0) suggesting magmatic associations. Two sapphires with syngenetic inclusions (zircon, Nb-rich rutile) gave U–Pb (Th-disequilibrium corrected) ages at ca 0.93 ± 0.1 Ma. The Bo Loei sapphires show higher Fe and Ga than other magmatic sapphire suites elsewhere in Cambodia (Pailin), Laos (Ban Huai Sai, Ban Sam Sai), South Vietnam (Dak Nong, Dak Lac) and SE Thailand (Chanthaburi-Trat). This suggests potential for geographic typing of sapphire suites between these different fields. 相似文献
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Hong Haoyuan Shahabi Himan Shirzadi Ataollah Chen Wei Chapi Kamran Ahmad Baharin Bin Roodposhti Majid Shadman Yari Hesar Arastoo Tian Yingying Tien Bui Dieu 《Natural Hazards》2019,96(1):173-212
Natural Hazards - The aim of this research is to investigate multi-criteria decision making [spatial multi-criteria evaluation (SMCE)], bivariate statistical methods [frequency ratio (FR), index of... 相似文献
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《Marine Policy》2017
Our global oceans are threatened by climate change, overfishing, pollution and a growing list of other impacts that demonstrate an urgent global need for sustainable ocean management. Whilst marine conservation initiatives and protected ocean spaces have increased over recent years, ocean management still lags behind the terrestrial sectors in incorporating and involving communities in its development. ‘Social licence to operate’ is used broadly across the terrestrial literature, but its understanding and application within the marine has been limited to date. This review sought to collate and synthesise instances of social licence in the marine realm as documented in the literature, aiming to create an understanding that may inform future research and development of social licence. Its results determine that social licence is yet an emergent concept in the marine sector but there may be great potential for its application in the marine context. Social licence has become an important theme for development in marine industry and resource use, particularly towards exploring communication and stakeholder engagement. This paper identifies future themes and areas requiring investigation and application in this domain. 相似文献
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Modernisation of the International Convention for the Regulation of Whaling (ICRW) has long been proposed by some contracting states and outsiders as a way of resolving the “Whaling Dispute” within the International Whaling Commission (IWC); however, both sides of the debate have traditionally been unconvinced that they would gain enough benefit to make the process worthwhile. 相似文献
20.
《Precambrian Research》1986,32(4):343-368
Late Archaean granites have been identified within the northern part of the Napier Complex of Enderby Land, Antarctica, although intrusives of this age are not common elsewhere in the complex. The oldest intrusive (3070 ± 34 Ma), synorogenic granite at Proclamation Island, was probably derived from melting of felsic crustal rocks of igneous origin. Two younger granites were emplaced at about 2840 Ma and 2481 ± 3 Ma, and the latter has geochemical similarities with other late and post-orogenic intrusives elsewhere in the East Antarctic Shield. Because of their fractionated character, it is difficult to discern whether the granites were derived by melting of sedimentary or igneous protoliths, but a granulite-facies source is probable.TNdCHUR model ages of the three analysed granites suggest that the Napier Complex is the product of at least two temporally discrete episodes of continental crust formation. The granite precursors probably formed at about 3100 Ma, whereas most of the exposed Napier Complex is much older (back to almost 4000 Ma). Two of the granites appear to record a significant hiatus (in one case of about 600 Ma) between the formation of this crustal precursor and final emplacement. The 3100 Ma old episode of crustal formation was roughly synchronous with a widespread, intense, and high-grade tectonothermal event (D1-M1), which produced metamorphic fabrics and mineral assemblages that are widely preserved within the Napier Complex. It is therefore likely that this new crust formation, deformation and metamorphism are all attributable to a single tectonic episode, possibly related to emplacement of magma into the lower crust. The two younger granites were emplaced at about the time of two subsequent and less intense tectonothermal events (D2-M2 and D3-M3).Concordant Rb-Sr total-rock and U-Pb zircon ages, which are interpreted as emplacement ages, have been obtained for two of the intrusions. However, the third exhibits the unusual relationship of a Rb-Sr isochron age older than the U-Pb zircon age. In this case the Rb-Sr age is believed to date magmatic emplacement. The complex interpretation required for the zircon data is forewarned by a non-perfect alignment of analytical points, in contrast to the perfect analytical alignments produced by the isotopically coherent granites. Two of the three granites yield similar and relatively precise lower intercepts with the U-Pb concordia but these do not appear to have direct geological significance.The new isotopic data are combined with earlier results to derive an integrated tectonothermal evolution for the Napier Complex. 相似文献