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781.
宝塔滑坡是1个基岩古滑坡,本文把它作为1个实例,分析为什么进行了3次大规模勘探仍然出现范围边界的错误,这涉及到古滑坡确定的证据、分析判断方法、勘探方向与方法等问题.确定滑坡的根据主要依据各种滑坡地质现象与滑坡地形地貌证据,除滑面证据外,许多所谓滑坡的地质、地形、地貌现象都具有多解性,因此要进行多因素综合对比分析.本文对...  相似文献   
782.
随着我国居民生活水平的日益提高,人们对城市居住区的选取提出了更高的要求。本文基于ArcGIS的空间分析功能,对不同的居住区进行分析和比较,在分析过程中分别选择一些具有代表性的影响因素,通过这些影响因素对城市居住区宜居性进行空间评价。  相似文献   
783.
FACTORS AFFECTING FORMATION AND DEVELOPMENT OF THE URBAN INDUSTRIAL DISTRICT IN CHINA──A Case StudyonCaohejingHi-TechParkinSh...  相似文献   
784.
天宫一号数据地表温度反演及其在城市热岛效应中的应用   总被引:2,自引:1,他引:1  
针对天宫一号高光谱成像仪红外波段数据提出了一个单通道地表温度反演算法,算法的输入参数为大气水汽含量和地表发射率.利用模拟数据和黑河流域生态—水文过程综合遥感观测联合试验的地面实测数据对算法进行了精度评价,结果表明算法的均方根误差为2.72 K,能够满足大多数应用研究的需求.以北京市二环以内为研究区域,采用4个时相的天宫一号高光谱红外波段数据进行了城市热岛效应研究,结果表明天宫一号高光谱红外波段数据适合用来进行街区尺度的城市热岛效应研究,具有很大的应用潜力.  相似文献   
785.
刘晓燕  刘峰  夏英晓  李刚 《山东地质》2011,(2):35-37,41
以烟台市牟平区为例,选用人均建设用地标准法、户均宅基地标准法和农村居民点内部土地闲置率法3种方法,对农村居民点土地整理潜力测算方法进行了比较研究。指出农村居民点整理潜力测算方法的选择要根据测算区域内农村居民点的用地结构、发展状况等实际情况进行确定。  相似文献   
786.
本文通过典型矿床实例,分析了广东省中大型钨矿的产出环境,预测了其深部和外围的潜力.划分出7个最小预测区,通过面积类比预测了广东省钨矿的全部潜力,认为广东省钨矿潜力巨大,建议优先开发粤北地区的几个重要的远景区.  相似文献   
787.
Coastal flooding is a significant risk on the shores of Languedoc-Roussillon. The storms that periodically hit the coast can generate strong swells and storm surges. Most beach resorts, built on a low elevation dune ridge, are periodically flooded during major storms. Although risks zoning regulations take into consideration coastal flood hazards, the delineation of vulnerable areas is still insufficient and the commonly accepted threshold is regularly exceeded during most severe storms. This paper presents a method to improve the assessment of extreme storm-related water levels. It relies on fieldwork carried out in the Leucate commune (Aude), which is particularly exposed to the risk of sea level rise. It considers both storm surges and wave phenomena that occur within the surf zone (set-up and swash), calculated from the Simulating WAves Nearshore (SWAN®) numerical wave model and the Stockdon formula. Water levels reached during several recent storm events have been reconstructed and simulations of submerged areas were carried out by numerical modelling.  相似文献   
788.
The Middle–Lower Yangtze River metallogenic belt (MLYRMB), extending from Daye in Hubei Province in the west to Zhenjiang in Jiangsu Province in the east, hosts a number of large polymetallic (Cu–Au–Mo, Fe, Zn, Pb, and Ag) deposits and constitutes one of the most important metallogenic belts in China. The Cu–Au–Mo deposits in the Jiurui district are an important component of the MLYRMB. In this study we carried out precise and detailed zircon U–Pb dating for all types of magmatic rocks from the Wushan ore deposit in the Jiurui district. Three samples of Cu–Au–Mo-related porphyries from different ore belts at Wushan were analyzed and yielded zircon U–Pb ages of 148.0 ± 1.0 Ma, 145.4 ± 0.9 Ma and 147.3 ± 0.9 Ma, respectively. A series of dykes were emplaced immediately following the Cu–Au–Mo-related porphyries at Wushan. A dark-colored basic dyke which intruded into the granodiorite porphyry at Wujia gold deposit near Wushan was dated at 144.5 ± 1.2 Ma. Two lamprophyre dykes taken from the north ore belt at Wushan underground mining stops were dated at 143.6 ± 0.9 Ma and 144.3 ± 0.9 Ma, respectively. A late-stage dyke which was also taken from the Wushan north ore belt yielded an age of 142.6 ± 1.0 Ma and might represent the end of magmatism in the Wushan ore deposit. These new geochronological data demonstrate that the time range of magmatism in the Wushan ore deposit is approximately between 148 Ma and 143 Ma, showing that the magmatic activity at Wushan was rapid and intensive. The ages of Cu–Au–Mo-related porphyries from other areas in the Jiurui district, such as the Dongleiwan, Yangjishan and Chengmenba ore deposits, were also measured and yielded zircon U–Pb ages of 141.5 ± 1.7 Ma, 143.4 ± 1.4 Ma and 146.6 ± 1.0 Ma, respectively. Combined with those previously reported zircon U–Pb age results from the Jiurui district, the present age data set demonstrates that extensive magmatism in the Jiurui district was coeval and intensive, marked by a magmatic activity in the age range of 148 to 138 Ma and peaked between 148 Ma and 142 Ma. According to the statistics of all those precise zircon U–Pb ages, the Cu–Au–Mo-related porphyries in the Edong and Tongling districts in the MLYRMB show similar ages, and they have a slightly younger peak age and a longer duration than that of the Jiurui district. The geographic shape of the MLYRMB in the Cretaceous shows an arcuate structure, the Jiurui district is located at the transitional point of the arcuate structure and the Edong and Tongling districts are situated on both sides of the arcuate structure. Considering that the Jiurui district has a slightly older peak age and a shorter duration of magmatic activity than that in the Edong and Tongling districts, it seems that the arcuate structure of the MLYRMB played an important role in the formation of these Cu–Au–Mo-related porphyries. Consequently, we suggest that the genesis of the Late Mesozoic magmatic rocks along the MLYRMB may have been due to a tectonic activity developed from southeast to northwest, which probably has a close relationship with the subduction of the paleo-Pacific plate beneath the Eurasian plate in Mesozoic times.  相似文献   
789.
通过对土地利用的多样化指数、集中化指数以及土地利用组合类型3种方法分析东港区土地利用结构,运用优势度指数和均匀度指数作为衡量土地利用空间布局的指数,对东港区土地利用结构和空间布局进行定量分析,得出该区土地利用集中化程度较低,土地利用总体功能不高。为全区土地利用的空间分布提供基础依据,对优化土地利用提供现实基础。  相似文献   
790.
马仁锋  吴杨  沈玉芳 《地理科学进展》2011,30(10):1276-1288
产业区是20世纪80年代以来经济地理学研究的核心领域之一,作为城市经济发展的重要场所及产物和城市空间类型之一,其形成与发展引起了国内外学界高度关注。梳理文献发现产业区研究主要集中在:本质探究、形成机理、演化时间过程及未来趋向等方面,然现有研究存在如下问题:①未能形成产业区演化研究的理论框架;②研究视角虽较为多元,但大都孤立地讨论产业区演化,研究思路过于追求学科特色而缺乏综合性研究逻辑,无法将其嵌入城市与区域发展之中;③鲜有关注以生产性服务业、创意产业为主导的产业区演化。针对现有问题,借鉴演化经济地理学从产业区演化的动力来源、时一空过程、景观表征入手,界定了产业区演化的概念和内涵,构建了产业区演化研究范式,并针对后工业社会创意产业区或创意集群的演化现象,提出了研究建议。  相似文献   
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