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131.
132.
羊八井地热田深、浅层热水都是Cl-Na类型,具有相同的B/Cl比值,说明深层热水在上升通道中与冷水相混合形成了浅层热水。浅层流体自西北向东南流动,温度逐渐降低。浅层热储内普遍存在着水岩交换反应,对热水的化学组成有一定的影响。石英和玉髓地热温度计分别适用于计算深、浅层的热储温度。纳木错(湖)不是羊八井地热田的补给区。深层热水在井筒内绝热汽化时不会出现SiO2结垢,CaCO3是否会在井筒壁沉淀需要放喷较长时间来检验。文中还阐述了对热水的化学组分进行监测的必要性。 相似文献
133.
流域地貌系统定量研究的新指标 总被引:6,自引:3,他引:3
简要介绍了分形基本理论,着重讨论了流域地貌系统定量研究的指标.水系分维的计算方法,水系分维区域划分原则及其应用含义. 相似文献
134.
TECTONICac~ac~~RA~m~NERGoorU~YANG~~oafNdsreof~actTheho~ofUPperYangtzePlatformwascpetallizedandconsolidatedinthekiaogUanhernovernentofMeSoproterocoic(ca.1700mp.ItconstituteSthestableCentralSichuanconiinelhalnucleusandthecratonakin.Therearetabtabofcontinental~ionsurroUndingtheCentralSichuanconti~alnuCleusduring1700--800the.ThebordersofthecontinentalaCCretionareconcordantacthebordersof~nicandPalcogngnphy,andalsofo~theboundarybet~basin~formationS.InPaloocoic,tab~nicCycleScormspond… 相似文献
135.
近百年长江下游作物生长季冷暖的变化与大型环流的振动 总被引:2,自引:1,他引:2
本文运用上海1373—1982年110年气温资料,配合1871—1980年110年月平均海平面气压场资料,分析了长江下游作物生长季冷暖的长期变化以及与之关联的大型环流变化特征。发现最近百余年里,年、季(代表月份)和关键旬的平均气温普遍经历了从偏冷期转为偏暖期约80—100年周期的振动,转折发生在本世纪20年代末、30年代初。70年代前后有转向偏冷期的趋势。这类低频振动与大型环流活动的低频振动有密切关联,主要表现在冬季亚洲大陆冷高压主体偏东和阿留申低压偏弱时期,相应夏季青藏高原热低压偏弱时期,对应长江下游偏冷期;反之,则对应偏暖期。讨论了生长季冷暖变化对农作物生长发育和产量的影响。 相似文献
136.
In this paper, by means of the “CWH” (circulation-weather and climate-agricultural harvest) analytical meth-od, drawing from the monthly mean long-term data of the global sea level pressure field and annual precipitation data and grain yield data of some regions in East Asia, the time-space characters of low-frequency fluctuation of East Asian precipitation with band distribution are analyzed.It is revealed that the band of 20-30 years quasi-periodic fluctuation is located in Southeast Asia and the coastal areas of South China. Moving forward to west and north, the period of fluctuation of precipitation tends to become longer, both bands, with about 40-yr and 60-80-yr quasi-periodic fluctuation are respectively situated in the middle-lower reaches of the Yangtze River and North or Southwest China. Furthermore, the relationships between the fluctuations of precipitation bands and large-scale circulations are analyzed. The relationships between precipita-tion and types of water resources are discussed as well. In addition, the tendency of long-term variation in rainfall is predicted. 相似文献
137.
晚奥陶世与早志留世之间的都匀运动,使滇中古隆起与黔中古隆起成为一整体隆起带(习惯上称黔中古陆),把滇东南和黔南与滇东北-黔北-川南分隔为南、北两个不同的构造沉积域。南侧的曲靖一带出露下、中寒武统,其上分别与中、上志留统和下泥盆统呈假整合,其间缺失奥陶纪和早志留世的沉积物。北侧的禄劝-武定一带,下古生界的沉积序列与之相反,有完整的奥陶纪沉积组合,上与泥盆系假整合,其间无志留纪的沉积。这表明黔中古陆两侧的沉积域各为独立的系统。中晚志留世,黔中古隆起南侧应归属于上扬子与滇黔桂地块前陆挠曲盆地的一部分,由曲靖向北东经赫章哑都-贵阳南转向湘西,向南则与云南的绿春海相连,黔中古隆起北侧的沉积域则为上扬子前陆(川南-黔北)盆地的边缘相。 相似文献
138.
沿河县地质灾害特征、成因及防治 总被引:1,自引:0,他引:1
本文对贵州省沿河县地质灾害的地质背景进行了调查研究,指出了该县地质灾害的特征和成因及其防治途径。 相似文献
139.
Partial Melting and Its Implications for Understanding the Seismic Velocity Structure within the Southern Tibetan Crust 总被引:2,自引:0,他引:2
YANG Xiaosong MA Jin JIN Zhenmin GAO Shan MA Shengli Geology Institute China Seismological Bureau Beijing Laboratory of Tectonophysics China Seismological Bureau Beijing Faculty of Earth Sciences China University of Geosciences Wuhan Hubei 《《地质学报》英文版》2003,77(1):64-71
In order to constrain the crustal wave velocity structure in the southern Tibetan crust and provide insight into the contribution of crustal composition, geothermal gradient and partial melting to the velocity structure, which is characterized by low average crustal velocities and widespread presence of low-velocity zone(s), the authors model the crustal velocity and density as functions of depth corresponding to various heat flow values in light of velocity measurements at high temperature and high pressure. The modeled velocity and density are regarded as comparison standards. The comparison of the standards with seismic observations in southern Tibet implies that the predominantly felsic composition at high heat flow cannot explain the observed velocity structure there. Hence, the authors are in favor of attributing low average crustal velocities and low-velocity zone(s) observed in southern Tibet mainly to partial melting. Modeling based on the experimental results suggests that a melting percentage 相似文献
140.
Progress and prospects of applied research on physical geography and the living environment in China over the past 70 years (1949–2019) 总被引:2,自引:1,他引:1
Chen Fahu Wu Shaohong Cui Peng Cai Yunlong Zhang Yili Yin Yunhe Liu Guobin Ouyang Zhu Ma Wei Yang Linsheng Wu Duo Lei Jiaqiang Zhang Guoyou Zou Xueyong Chen Xiaoqing Tan Minghong Wang Xunming Bao Anming Cheng Weixin Dang Xiaohu Wei Binggan Wang Guoliang Wang Wuyi Zhang Xingquan Liu Xiaochen Li Shengyu 《地理学报(英文版)》2021,31(1):3-45
Physical geography is a basic research subject of natural sciences.Its research object is the natural environment which is closely related to human living and development,and China's natural environment is complex and diverse.According to national needs and regional development,physical geographers have achieved remarkable achievements in applied basis and applied research,which also has substantially contributed to the planning of national economic growth and social development,the protection of macro ecosystems and resources,and sustainable regional development.This study summarized the practice and application of physical geography in China over the past 70 years in the following fields:regional differences in natural environments and physical regionalization;land use and land cover changes;natural hazards and risk reduction;process and prevention of desertification;upgrading of medium-and low-yield fields in the Huang-Huai-Hai region;engineering construction in permafrost areas; geochemical element anomalies and the prevention and control of endemic diseases;positioning and observation of hysical geographical elements;and identification of geospatial differentiation and geographical detectors. Furthermore, we have proposed the future direction of applied research in the field of physical geography. 相似文献