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1.
This study aims to investigate two important issues: what are the determinants of public goods investment and what is the government's investment behavior in mountainous areas. The impacts of natural conditions, target, and demand elements on public goods investment are analyzed with statistical method, and the determinants of public goods investment in the areas are obtained by using population-weighted and stepwise regression models with Eviews6.0 software with survey data in 2008 and calculated data based on GIS of 20 typical villages in mountainous regions in Sichuan, China. The results showed: (1) natural conditions are the important determinants of public investment. Mountainous villages with steep slope have relatively high levels of investment; (2) concentration of population and the educational levels of the village leaders also have important impacts on public goods investment; (3) the government is more concerned with public investment resources particularly in areas characterized by fragile ecological environment and poor agricultural output. These results suggest that the current investment strategy helps to reduce disparities in regional development.  相似文献   

2.
Mineralogical analysis was performed on bulk sediments of 79 surface samples using X-ray diffraction. The analytical results, combined with data on ocean currents and the regional geological background, were used to investigate the mineral sources. Mineral assemblages in sediments and their distribution in the study area indicate that the material sources are complex. (1) Feldspar is abundant in the sediments of the middle Chukchi Sea near the Bering Strait, originating from sediments in the Anadyr River carried by the Anadyr Current. Sediments deposited on the western side of the Chukchi Sea are rich in feldspar. Compared with other areas, sediments in this region are rich in hornblende transported from volcanic and sedimentary rocks in Siberia by the Anadyr Stream and the Siberian Coastal Current. Sediments in the eastern Chukchi Sea are rich in quartz sourced from sediments of the Yukon and Kuskokwim rivers carried by the Alaska Coastal Current. Sediments in the northern Chukchi Sea are rich in quartz and carbonates from the Mackenzie River sediments. (2) Sediments of the southern and central Canada Basin contain little calcite and dolomite, mainly due to the small impact of the Beaufort Gyre carrying carbonates from the Canadian Arctic Islands. Compared with other areas, the mica content in the region is high, implying that the Laptev Sea is the main sediment source for the southern and central Canada Basin. In the other deep sea areas, calcite and dolomite levels are high caused by the input of large amounts of sediment carried by the Beaufort Gyre from the Canadian Arctic Islands (Banks and Victoria). The Siberian Laptev Sea also provides small amounts of sediment for this region. Furthermore, the Atlantic mid-water contributes some fine-grained material to the entire deep western Arctic Ocean.  相似文献   

3.
The Urad Zhongqi mafic intrusions crop out in western Inner Mongolia and are dominated by hornblende gabbro.Zircon LA-ICP-MS U-Pb dating indicates that the mafic pluton was emplaced in the Early Permian(272 ± 3Ma).The hornblende gabbro rocks have low concentrations of Si O2,high total Fe2O3,Mg O,Ni,Co,Sc and Cr.The rocks are characterized by selective enrichment of large ion lithophile elements(LILE) and light rare earth elements(LREE),and depletion in high field strength elements(HFSE)(e.g.Nb,Ta,Zr,Hf,P and Ti).It suggests that they formed from a primary magma generated by the partial melting of lithospheric mantle material had been previously modified by subduction-related fluids.According to the geochemical data and the geology of the region,the authors found that the Early Permian hornblende gabbroic in western Inner Mongolia formed in a post-collisional extensional setting.  相似文献   

4.
Zircon LA-ICP-MS U-Pb age and whole-rock geochemistry data are presented for the Hutouya granodiorite porphyries in Mengyin,western Shandong,to restrict its petrogenesis.The analyzed zircons exhibit oscillatory growth zoning and core-rim textures in the cathodoluminescence images and have high Th/U ratios( 0.04--1.66),indicating its magmatic origin.The youngest group of magmatic zircon yields weighted mean~(206)Pb/~(238) U age of 132 ± 2 Ma,which represents the forming age of the granodiorite porphyries,i.e.,the Early Cretaceous.The oldest group of magmatic zircon~(207)Pb/~(206) Pb ages ranges from 2 398 Ma to 2 370 Ma,yielding a weighted mean age of 2 389 ± 23 Ma,suggesting that the basement of the North China Craton should exist in the research area.Geochemically,the samples are characterized by high Si O_2( 70.38% and 64.87%),low Mg O( 0.60% and 1.53%) and Mg~#values( 42.92 and 50.42).Moreover,they show enrichment of light rare earth elements and large ion lithophile elements( e.g.Rb,Ba and K),depletion of heavy rare earth elements and high field strength elements( e.g.Nb and Ta),positive anomaly of Pb,and negative anomaly of Ti.These results,together with previously published data,indicate that the Hutouya granodiorite porphyries were derived from partial melting of a delaminated lower continental crust and subsequent interaction with the mantle peridotites.They are consistent with the period of lithospheric thinning beneath the eastern North China Craton and may be formed in an extensional tectonic environment.  相似文献   

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