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101.
The chemical composition of water samples was studied from different caves in Slovakia. The water samples were collected from caves of two karst regions: (1) the Demänovský Cave System (DCS), situated in the Low Tatra Mountains (Northern Slovakia), which is mainly formed of limestone and dolomites; and (2) the Slovakian Karst to the Southeast is formed of limestone. A considerable difference between water from the two regions was shown. The waters from the DCS, that were controlled by vadose water percolating through different types of host rocks, contained more Mg ions than those from the Slovakian Karst caves whereas, the concentration of SO4 was controlled by the dissolution of displacive gypsum and/or oxidation of pyrite. The distribution of NO3 in the studied samples was random, hence nitrates probably derived from few pollution sources. The total mineralization of the water was covariant with calcite and aragonite saturation indices. In general, both parameters are higher in the Slovakian Karst caves than in the DCS. It is controlled probably by differences in climatic conditions, soil and plant covers between these two regions. The main goal of this article is to characterize the major-ion water chemistry within the studied caves as well as some microelements. The results have confirmed the dominant role of the bedrock petrography in forming the general chemistry of cave waters. 相似文献
102.
武汉市星级饭店空间布局研究 总被引:8,自引:0,他引:8
服务业设施空间布局和结构特征一直是学术界研究的重点领域。以武汉市的110家星级饭店为研究对象,运用GIS空间分析工具,分析和探讨了其空间布局特征和规律。结果表明:(1)武汉市星级饭店在等级规模上表现为纺锤形结构,在空间分布上呈现出核心-边缘结构;(2)武汉市核心区内星级饭店的空间布局特征表现为向主要交通干线集聚和向主要商业发达地区(汉口火车站周边地区、滨江公园-解放公园-中山公园所围的三角形区域以及武昌小东门-洪山广场区)集聚。从而得出了武汉市星级饭店空间布局两大影响因素:交通区位条件和工商业发达程度。 相似文献
103.
闽西龙岩龙崆洞风景区地下岩溶发育,6层水平溶洞与竖洞、斜洞纵横相接,总面积5.4×104m2。景区有大小景点百余处,其成因以碳酸盐岩岩溶为主,兼有花岗岩山岳地貌及动植物景观。 相似文献
104.
Data with the 2MASS prototype camera were obtained in a 2.3 sq. deg region in Taurus containing Heiles Cloud 2, a region known from IRAS observations to contain a number of very young solar type stars. Data at 1.25 (J), 1.65 (H), and 2.2 (K
s
)µm are presented. These data are representative of the type and quality of data expected from the planned near-IR surveys, 2MASS and DENIS. Near-IR surveys will be useful for determining the large scale variation of extinction with clouds, for determining the luminosity function in nearby clouds down to ranges of 0.1–1.0 L, and for finding highly extincted T Tauri stars missed by IRAS because the bulk of their luminosity is emitted shortward of 12µm. 相似文献
105.
We present the first results of a survey of Blue Compact Galaxies with a 10 m array. Blue Compact Galaxies (BCGs) are dwarf galaxies experiencing an intense burst of star formation. As dwarf systems, their main characteristics is a low heavy-elements abundance. Although dust is thought to be less abundant in these galaxies than in normal spirals, the presence of a compact starburst region favors a detection in the infrared, and 10 m imaging is perfectly suited to star formation studies in BCGs since it focuses on the hottest dust inside the star-forming regions. 相似文献
106.
周口店第一地点洞穴四十余米厚的堆积层自下而上共分为 17层 ,新近测量的年代推前了近 2 0 0 ka。对堆积层所含哺乳动物化石和孢粉资料进行聚类统计和因子分析 ,结合风化系数和微量元素含量等古气候代用指标 ,重新定量地描绘它所记录的古气候波动旋回。根据第 2层 TIMS测年为 410 ka B.P.,第 14层上部是磁性地层测量的B/ M界线 ,可以将该洞穴堆积层 1— 14层对比于深海岩心 δ1 8O气候曲线的 11— 19段或中国黄土—古土壤序列S4— S7,并且古气候旋回内的次级波动也可进行一定程度的对比。 相似文献
107.
云南喀斯特洞穴型旅游目的地生命周期调控机制研究 总被引:9,自引:0,他引:9
喀斯特洞穴是一种特殊的旅游资源,具有地域上的普遍性、共性大,独特性小、空间竞争替代性强、开发后资源本身变化大等方面的特征。同时,喀斯特洞穴又具有特殊的旅游生命周期,往往没有探查阶段和参与阶段,直接进入发展阶段。因此,以Butler旅游地生命周期理论为支撑,通过实地调查,对喀斯特洞穴型旅游目的地的生命周期进行详细研究,并结合典型案例分析,编制喀斯特洞穴旅游地生命周期曲线,分析影响曲线的因子,提出调控喀斯特洞穴旅游地生命周期的途径和方法,将对喀斯特洞穴型旅游目的地的开发具有重要的指导意义。 相似文献
108.
利用乌什台数字化前兆形变观测资料,分析乌什MS 4.5级地震前乌什台水管倾斜仪、洞体应变仪数据变化情况。通过对比分析发现:地震前,洞体应变仪北南分量数据曲线正常,东西分量数据曲线加速拉张,05:14-20:32拉张幅度达到7.40×10-7,7月19日5时至20日16时乌什洞体应变仪东西分量快速拉张了9.20×10-7;7月19日5-19时,水管倾斜仪北南分量数据曲线正常,东西分量数据曲线反向西倾7.13ms,且05:59-06:06、07:36-07:46、18:42-18:56数据掉格,水管倾斜仪异常结束后1小时,在洞体应变仪异常过程中发生了乌什MS 4.5级地震。水管仪东西分量震前反向西倾,洞体应变仪东西分量震前拉张加速,短临异常明显,且2套形变观测震前异常时间同步性较好。 相似文献
109.
Our understanding of the chronological sequence of Pleistocene land mammal faunas (including hominids) preserved in caves and fissures in the karstic terrain of subtropical southern China has been greatly impeded by the discontinuous nature of the strata yielding the fossils. A contributory issue is the lack of suitable elements for numerical dating, especially for the Early Pleistocene cave sediments. Here we present new magnetostratigraphic dating results for five cave sedimentary sequences in the Bubing Basin, Guangxi Zhuang Autonomous Region, which contain the typical Pleistocene Gigantopithecus fauna and Ailuropoda–Stegodon fauna of southern China. The five karstic caves are situated at elevations ranging from 252 m to 191 m above sea level. The integrated dating results reveal that the five cave sedimentary sequences span an age range from the late Gauss normal Chron to the early Brunhes normal Chron. The faunas are assigned to >2.6 Ma (Mohui–houshan Cave), 1.95–1.78 Ma (Mohui Cave), 0.99–0.78 Ma (Baolai Cave) and ∼0.7 Ma (Upper Wuyun and Ganxian Caves). Furthermore, by combining our new magnetostratigraphy work with previously published magnetostratigraphic, U–series and electron spin resonance dating results, a chronological sequence of the Plio–Pleistocene mammalian faunas from cave sites in southern China has been established. The chronological sequence contributes to an improved understanding of the evolutionary processes of Plio–Pleistocene land mammals, as well as of early humans in subtropical southern China. 相似文献
110.
文章分析了临汾台水平摆、垂直摆两套洞体形变观测仪记录曲线的正常变化形态,讨论了人为和自然因素引起干扰的图像特征,以及山西带南部3次中等地震前典型异常图像特征,分析结果为今后观测数据处理、异常识别及异常跟踪分析判定提供参考。 相似文献