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1.
????GPS??????????????山???????α????????????????????????????о??????????????о?????????????????????????????????????????С??????????????о???????????????????????????????-???????????????-?????????????????????????????????-?????????????????????????????-??????????-?????????????????????????????????  相似文献   
2.
西湖凹陷位于东海大陆架边缘,地壳为相对软弱的过渡壳。西湖凹陷中新世末以前属于萎缩型盆地,上新世伴随冲绳海槽的形成才成为扩张性盆地。受构造控制盆地萎缩期沉积有以下3个特点:第一,整体表现为海退;第二,沉积范围逐次减小;第三,泥岩百分比越来越低,盖层条件越来越差。平湖组存在区域盖层,钻遇断块气藏;花港组存在局部盖层,背斜充满度高,断背斜充满度低,断块未成藏;新近系盖层条件更差,断背斜亦未能成藏。由此可见保存条件是西湖凹陷油气成藏的主控因素,保存条件好的领域是西湖凹陷下一步勘探的方向。  相似文献   
3.
安徽铜陵狮子山矿田铜、金共生与分离的热力学研究   总被引:4,自引:0,他引:4  
狮子山矿田是安徽铜陵矿集区内最具代表性的大型铜金多金属矿田.矿田内铜、金矿床或矿体既各自独立产出,义相互共生或伴生,铜矿化和金矿化在时间上和空间上存在既共生又分离的现象.本文选择矿田内代表性铜矿床和金矿床开展系统的流体包裹体地球化学研究,并进行成矿流体中铜、金溶解度的热力学理论计算和1分析,探索铜、金共生与分离的机制和...  相似文献   
4.
冰雪旅游是推动冰雪经济与旅游产业高质量融合发展的重要途径,现已成为文旅产业中最具潜力的领域之一。然而在全球气候变化的影响下,冰雪旅游发展面临严峻挑战。文章以北京市为例,运用结构方程模型对冰雪旅游情境中城市居民的气候变化感知、感知价值、旅游意向和环境责任行为等变量间的影响关系及其形成机制进行分析。研究发现:(1)气候变化感知分为气候变化表征和气候变化风险两个维度,且两者显著正向影响冰雪旅游感知价值。同时,气候变化风险显著正向影响旅游者环境责任行为。(2)冰雪旅游感知价值显著正向影响冰雪旅游意向和环境责任行为。(3)冰雪旅游意向显著正向影响环境责任行为。(4)旅游经历在气候变化感知对冰雪旅游意向和环境责任行为的影响关系中具有显著的正向调节作用。本研究对厘清冰雪旅游情境下气候变化感知对游客环境责任行为的复杂影响机理具有重要的理论价值,同时也能够在一定程度上为相关部门把握“后冬奥”黄金机遇,推动冰雪旅游高质量发展提供决策参考。  相似文献   
5.
商业空间结构是城市经济活动的重要载体,识别商业中心和商业热点区以及探究其影响因素对于商业资源优化配置显得尤为必要,进而指导城市有序发展。论文以乌鲁木齐主城区为例,利用开放平台大数据兴趣点(point of interest, POI),采用地理学空间统计方法定量识别商业中心和商业热点区,对商业分布和空间集聚特征进行分类和解读,并利用地理探测器方法探寻其影响因素。主要结论如下:① 乌鲁木齐市商业高值区分布在吐乌大高速—和平渠沿线地带,大型商业中心主要有南湖商圈、中山路商圈、友好商圈、会展商圈、米东商圈、铁路局商圈。② 商业热点区呈现“T型”双轴分布,北部新城商业地带与南部传统商业地带共同构成乌鲁木齐市最具活力的商业地带;6类商业热点区的分布可归纳为3种类型,商务和金融服务类为单一点状型,住宿和餐饮服务类为带状延伸型,生活与购物服务类为带状双核型。③地价、集聚效应、路网密度等是影响商业宏观分布的主要因素,其次为人口密度和中心可达性,自然因素如高程、地形起伏度等对商业布局影响有限;各因素对不同类型商业业态的影响程度各异,如人口密度、路网密度对购物类影响较大,中心可达性和地价对于商务、金融类影响较大;就各业态类型网点间的关系而言,商务和金融类协同作用强,餐饮与购物类协同效应较强,共同影响城市商业空间。  相似文献   
6.
Recent climate change is substantially affecting the spatial pattern of geographical zones, and the temporal and spatial inconsistency of climatic warming and drying patterns contributes to the complexity of the shifting of temperature and aridity zones. Eastern Inner Mongolia, China, located in the interface region of different biomes and ecogeographic zones, has experienced dramatic drying and warming over the past several decades. In this study, the annual accumulated temperature above 10 °C (AAT10) and the aridity index, two key indicators in geographical regionalization, are used to assess warming and drying processes and track the movements of temperature and aridity zones from 1960 to 2008. The results show a significant warming at the regional level from 1960 to 2008 with an AAT10 increase rate of 7.89 °C·d/year (p?<?0.001) in Eastern Inner Mongolia, while the drying trend was not significant during this period. Spatial heterogeneity of warming and drying distributions was also evident. Analysis of warming and drying via piecewise regression revealed two separate, specific trends between the first 31 years (1960–1990) and the subsequent 18 years (1991–2008). Generally, mild warming and very slight wetting occurred prior to 1990, while after 1991 both warming and drying were significant and enhanced. Continuous warming drove a northward shift of temperature zones from the 1960s to 2000s, while aridity zones displayed enhanced temporal and spatial variability. Climate change effects on temperature and aridity zones imply that the patterns of cropping systems, macro-ecosystems, and human land use modes are potentially undergoing migration and modification due to climate change.  相似文献   
7.
Improving the understanding of cropland change and its driving factors is a current focus for policy decision-makers in China. The datasets of cropland and cropland changes from the 1970s to the 2000s were used to explore whether climate change has produced spatio-temporal changes to cropland in northern China since the 1970s. Two representative indicators of heat and water resources, which are important determinants of crop growth and productivity, were considered to track climate change, including active accumulated temperatures ≥10 °C (AAT10) and the standardized precipitation evapotranspiration index (SPEI). Our results showed that rapid cropland change has occurred in northern China since the 1970s, and the area of cropland reclamation (10.23 million ha) was much greater than that of abandoned cropland (2.94 million ha). In the 2000s, the area of cropland with AAT10 higher than 3,000 °C·d increased, while the area of cropland with an SPEI greater than 0.25 decreased compared to the 1970s, 1980s and 1990s. It appears that climate warming has provided thermal conditions that have aided rapid cropland reclamation in northern China since the 1970s, and drier climatic conditions did not become a limiting factor for cropland reclamation, especially from the 1990s to the 2000s. Approximately 70 % of cropland reclamation areas were located in warmer but drier regions from the 1990s to the 2000s, and approximately 40 % of cropland abandonment occurred in warmer and wetter conditions that were suitable for agriculture during the periods from the 1970s to the 1980s and the 1990s to the 2000s. Our results suggest that climate change can be considered a driving factor of cropland change in the past several decades in northern China, in addition to socioeconomic factors.  相似文献   
8.
西藏东南部嘉黎断裂新知   总被引:28,自引:1,他引:28       下载免费PDF全文
任金卫  沈军  曹忠权 《地震地质》2000,22(4):344-350
野外调查表明 ,西藏东南部的嘉黎断裂带从那曲到嘉黎由三段呈雁行排列 ,大致沿N60°W方向延伸 ,其东南段在波密附近向南转折 ,沿贡日嘎布曲向南南东过上察隅和下察隅后转为近南北向延入缅甸境内与什阶断裂相连。嘉黎断层全新世以来活动性不强 ,其第四纪以来的平均滑动速率约为 4mm/a。一个有趣的现象是 ,虽然总体上嘉黎断裂的新活动不强 ,但在局部与张性盆地相邻的地段表现出较强的活动性 ,在这些段上沿断裂发育晚第四纪地表破裂 ,横跨断层的冲沟和河流被错断 ,其晚第四纪以来的平均滑动速率达到 15mm/a。但是这种现象的存在只局限在盆地中 ,盆地以外则截然终止 ,不复存在。从上述事实看 ,嘉黎断裂的走滑活动似乎是伴随张性活动而产生的 ,在断层几何和活动特征上类似于横切大洋中脊的转换断  相似文献   
9.
Li  Jinxiang  Zhao  Chenghai  Huang  Yong  Zhuo  Yuzhou  Li  Jinwei 《中国地球化学学报》2019,38(4):555-575
Acta Geochimica - The fault-controlled Nibao Carlin-type gold deposit, together with the strata-bound Shuiyindong deposit, comprise a significant amount of the disseminated gold deposits in...  相似文献   
10.
In order to study the major ion chemistry and controls of groundwater, 65 groundwater samples were collected and their major ions measured from wells within Lhasa River Basin. Groundwater has the characteristics of slightly alkaline and moderate total dissolved solid (TDS). TDS concentration ranged from 122.0 to 489.9 mg/L with a median value of 271.2 mg/L. Almost all the groundwater samples suited for drinking and irrigation. The major cations of groundwater are Ca2+ and Mg2+, accounting for 59.6 and 31.3% of the cations, respectively. Meanwhile, HCO3? and SO42? constituted about 56.7 and 36.9% of the anions, respectively, in Lhasa River Basin. The hydrochemical type of groundwater is HCO3-SO4-Ca-Mg. The chemical composition of groundwater samples located in the middle of Gibbs model, which indicates that the major chemical process of groundwater is controlled by rock weathering. Carbonate weathering was the dominant hydro-geochemical process controlling the concentration of major ions in groundwater within Lhasa River Basin, but silicate weathering also plays an important role.  相似文献   
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