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11.
地下空间地质环境适宜性评价是实现地下空间合理有序开发的重要环节,也是国土空间科学规划的必要前提。通过系统分析杭州市钱塘新区地质环境条件,从地形地貌、工程地质条件、水文地质条件、活动断裂及地震效应、环境地质问题等五个方面选取15个指标构建了地下空间开发地质环境适宜性评价指标体系。在此基础上,采用变权层次分析法和灰色关联分析模型,对浅层(0~ 15m)、次浅层(15~ 30m)、次深层(30~ 50 m)地下空间进行了开发利用地质环境条件适宜性评价。结果表明,研究区浅层和次深层地下空间更适宜开发,而次浅层地下空间适宜性好和适宜性较好的总面积仅占全区的45.7%,地质环境条件复杂,具有一定的开发难度。该结果可为钱塘新区地下空间合理开发提供参考。 相似文献
12.
兖州矿区煤中某些微量元素的赋存状态研究 总被引:6,自引:8,他引:6
微量元素的赋存状态决定其在煤的加工利用过程中释放的难易程度和毒性,弄清其在煤中的赋存状态,对准确评价元素的工艺性能、环境影响、作为副产品的可能性以及在地质意义上都是十分重要的。分析了微量元素在煤中的有机亲合性,采用数理统计方法,求得了微量元素与煤中有机显微组分、三态硫、灰分之间的相关性,并在浮沉实验的基础上,分析了微量元素的存在状态,通过研究向知,Ge、Ga、U、V、Cu、Th、Pb和Zn主要以无机态存在于煤中,F和Cl可能以有机态存在为主,As无机态和有机态存在的机率相似。 相似文献
13.
山西省大同市新荣区石墨矿带总体呈北东—南西向展布,长约22 km,赋矿层位为中下太古界右所堡组,岩性为含石墨黑云斜长片麻岩.目前该矿带上已有7个勘查区,累计查明晶质石墨矿物资源量约5000万吨,但对其矿床成因类型研究相对较少.本文收集整理和分析总结了区域内地质资料及化验分析结果,采用变质岩原岩恢复的四种方法确定该矿带的成因:从石墨矿带的矿体产状和岩石组合、岩相学和矿物学特征定性判断该矿带矿床为沉积岩区域深变质成矿类型;矿体样品地球化学微量元素比值(Sr:Ba等)符合副变质岩特征;稀土元素配分曲线及其研究表明矿体及围岩具有沉积岩变质特征;以TiO2-F图解、[(al+fm)–(c+alk)]/Si图解以及(al–alk):c图解展示的岩石化学特征半定量地确认新荣区石墨矿带矿床为以黏土岩为主的区域变质成矿.新荣区石墨矿带成因类型的确定填补了该区域矿床成因类型研究的空白,为下一步地质找矿及建模提供了重要依据;三种图解相结合,逐步缩小原岩范围,锁定原岩类型,为变质岩原岩恢复及矿床成因研究提供了新的思路和判别方法. 相似文献
14.
以国家扶贫攻坚重点地区——贵州乌蒙山七星关区为例,参考"全国地质资源环境承载能力评价与监测预警"形成的评价理论和方法,结合岩溶石山区地下水资源水文地质条件及开发利用实际,探索构建岩溶石山区县域范围内地下水资源承载能力评价方法。通过系统评价七星关区地下水资源承载能力,认为该区地下水资源承载能力较大,但资源、开采强度、劣质水分布不均,降低了部分区域地下水资源承载能力。评价结果为区域国土空间规划及"三区三线"划定提供了依据。同时,该评价方法亦为岩溶地区地下水资源承载能力评价提供了借鉴。 相似文献
15.
Moraine ridges and mounds of inferred Loch Lomond Stadial (LLS) age have been mapped at three sites (Fordingdale, Swindale and Wet Sleddale) in part of the eastern Lake District, northern England, and indicate glaciers were more widespread than envisaged by Sissons (1980, Transactions of the Royal Society of Edinburgh: Earth Sciences, Vol. 71, pp. 13–27). The moraines delimit closely the downslope/downvalley limits of the former glaciers but there is no geomorphological evidence with which to define their upslope/upvalley margins. The former glaciers are considered to have been nourished within the confines of their individual valley, cirque and hillside embayment respectively, rather than being outlet glaciers of plateau icefields. Estimated equilibrium line altitudes (ELAs) are within the range of values determined previously for LLS glaciers in the Lake District and do not necessitate revision of established palaeoclimatic parameters. Individual ELAs were probably influenced by local factors; all three former glaciers had accumulation-area aspects between north and east, limiting the impact of direct solar radiation during the ablation season, and were adjacent to extensive areas of high ground to the west and/or south that would have facilitated transfer of snow to their surfaces by winds from those directions. In Fordingdale, three essentially contemporaneous depositional landforms occur upslope of the moraines and are considered to represent hillslope adjustments following wastage of glacier ice from the site. © 1998 John Wiley & Sons, Ltd. 相似文献
16.
Distribution, abundance and life history characteristics of Mysis relicta were studied in the Feldberg Lake District (Lake Breiter Luzin, Lake Schmaler Luzin, Lake Zansen) located in northeastern Germany. Between July 2001 and November 2002 mysids were collected by vertical net hauls. In order to determine the impact of the current trophic conditions on the distribution of mysids in these lakes, oxygen concentration, total phosphorus, chlorophyll a and water transparency were also measured. All investigated lakes are mesotrophic at present. Lake Breiter Luzin exhibited great seasonal and spatial variations in mysid abundance. Density of adults and juveniles had a mean of 44.9 ± 57.1 and 68.7 ± 99.6 m−2, respectively. Highest abundance of adults was 110.4 ± 76.5 m−2 in summer, lowest abundances of 2.0 ± 4.0 m−2 occurred in spring. For juveniles, highest density of 218.4 ± 174.6 m−2 was detected in summer and lowest of 0.8 ± 1.8 m−2 in winter. No mysids were caught in any of the daytime hauls, but they were widely distributed throughout the water column at night. Size frequency distribution of mysids suggested that reproduction occurred year-round, the most consistent influx of juveniles occurred in early summer and a smaller second cohort in autumn. Highest mysid abundance was 189.2 ± 318.6 adults and 127.0 ± 66.3 juveniles m−2 in Lake Schmaler Luzin, and 59.6 ± 5.6 adults and 79.4 ± 11.2 juveniles m−2 in Lake Zansen. There were great spatial differences in abundance in both lakes. 相似文献
17.
18.
黔南布依族苗族自治州位于贵州省的中南部,与广西壮族自治区的河池、百色地区为邻。本文根据该地区多年实测水文资料分析降水、蒸发、水资源量、暴雨、洪水、泥沙和水质等水文特性。 相似文献
19.
Oasis is the core area of social and economic development in the arid western regions, and is also a territory with prominent ecological environmental problems. Because of the unreasonable development and utilization of soil and water resources, the ecological environment of oasis in Qingtongxia Irrigation District is threatened by soil salinization, shrinkage of lakes and wetlands, and deterioration of water environment. As for these environmental problems, the direct cause is the loss of regulation of groundwater depth or serious pollution of water caused by man-made irrational exploitation, and the root cause lies in shortage of water resources and unreasonable allocation of water resources. In this regard, it is believed that the primary task for the construction ecological environment of oasis in Qingtongxia Irrigation District is to adjust the allocation structure of water resources and to ease the contradiction between supply and demand of water resources, for which the direct means is to carry out dynamic control of water and salt based on the ecological landscape structure and land type in the Irrigation District in accordance with local conditions. 相似文献
20.
This paper briefly reviews the sociological literature on the “New” Chinatown phenomenon stressing its structural location
vis-à-vis the “Old” Chinatown and the homeland. It defines the New Chinatown as a panethnopolis, that is a global neighborhood
with a majority population of Chinese immigrants and of other ethnic groups of mostly Asian descent. It analyzes more particularly
the formation, development, and integration of San Francisco’s Richmond District’s New Chinatown into both the city where
it is located and the network of transglobal sites to which it belongs. It provides an interpretation of the New Chinatown
as a cultural enclave within the context of globalization theory. 相似文献