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121.
利用VB在GeoStar地理信息系统开发平台上进行二次开发,实现大庆油田采油一厂水泡子地理信息系统的3维数据查询与维护。介绍了系统的模块组成和功能,以及实现各项功能的关键技术。该系统灵活实用、功能较全,通过实际生产应用,反映出在地面水域地理信息数据计算与管理、直观显示等方面具有很好的实用价值。  相似文献   
122.
2000年度项目名单项目名称承担单位名称项目负责人批准经费(万元)中国西北地区典型大震遗迹保护中国地震局兰州地震研究所戴华光100.00中国地学大断面与深部地球物理资料整理中国地震局物探中心方盛明50.00磁暴基础数据库中国地震局地球物理研究所高玉芬70.00地震灾害基础数据的体系化建设中国地震局地质研究所聂高众90.00强震及工程震害资料基础数据库中国地震局工程力学研究所崔杰90.00中国大陆地壳应力环境基础数据库中国地震局地壳应力研究所谢富仁90.00高精度全球定位系统GPS数据库和共享系统中国地震局分析预报中心孙汉荣150.00城市…  相似文献   
123.
High‐salinity paleowater from low‐permeability aquitards in coastal areas can be a major threat to groundwater resources; however, such water has rarely been studied. The chemical and isotopic compositions of porewater extracted from a 200‐m‐thick Quaternary sedimentary sequence in the western coastal plain of Bohai Bay, China, were analyzed to investigate the salinity origin and chemical evolution of porewater in aquitards. Porewater samples derived at depths shallower than 32 m are characterized by Cl‐Na type saline water (total dissolved solids [TDS], 10.9–84.3 g/L), whereas those at depths greater than 32 m comprise Cl·SO4‐Na type brackish water (TDS, 2.2–6.3 g/L). Saline porewater is interpreted as evaporated seawater prior to halite saturation, as evidenced by Cl‐Br relationships. Although substantial dilution of saline porewater with meteoric water is supported by a wider Cl? range and δ2H‐δ18O covariance, the original marine waters were not completely flushed out. The deeper brackish porewater is determined to be a mixture of fresher porewater and brine groundwater and had a component of old brine of less than 10%, as indicated by a mixing model defined using δ2H and Cl? tracers. Porewater δ2H‐δ18O relationships and negative deuterium excess ranging from ?25.9‰ to ?2.9‰ indicate the existence of an arid climate since Late Pleistocene in Tianjin Plain. The aquitard porewaters were chemically modified through water‐rock interactions due to the long residence time.  相似文献   
124.
We developed the first tree-ring chronology, based on 73 cores from 29 Pinus tabulaeformis trees, for the Xiaolong Mountain area of central China, a region at the boundary of the Asian summer monsoon. This chronology exhibits significant (at 0.01 level) positive correlations with precipitation in May and June, and negative correlations with temperature in May, June and July. Highest linear correlation is observed between tree growth and the seasonalized (April–July) precipitation, suggesting that tree rings tend to integrate the monthly precipitation signals. Accordingly, the April–July total precipitation was reconstructed back to 1629 using these tree rings, explaining 44.7?% of the instrumental variance. A severe drought occurred in the area during the 1630s–1640s, which may be related to the weakened Asian summer monsoon caused by a low land-sea thermal gradient. The dry epoch during the 1920s–1930s and since the late 1970s may be explained by the strengthened Hadley circulation in a warmer climate. The dry (wet) epochs of the 1920s–1930s (the 1750s and 1950s) occurred during the warm (cold) phases of the El Ni?o-Southern Oscillation and the Pacific Decadal Oscillation that are often associated with weakened (strengthened) East Asian summer monsoon. These relationships indicate significant teleconnections operating over the past centuries in central China related to large-scale synoptic features.  相似文献   
125.
东北地区水稻障碍型低温冷害变化对区域气候增暖的响应   总被引:2,自引:0,他引:2  
胡春丽  李辑  焦敏  王婉昭  李晶  李菲 《气象科技》2015,43(4):744-749
利用东北地区153个气象站1961—2010年逐日气温资料,采用统计学方法分析了水稻障碍型低温冷害的气候变化特征及其对区域气候变暖的响应情况。结果表明,东北大部地区水稻障碍型低温冷害事件呈减少趋势,但区域性较为明显;障碍型低温冷害对关键发育期气温变化响应较为敏感,二者呈显著的负相关关系,表现为气温每升高1 ℃,东北地区冷害减少35个站次。东北地区关键发育期气温均呈上升趋势,但吉林西部地区障碍型冷害却随之增加,分析了关键发育期气温变率和气候变率,将其解释为局地障碍型冷害增加主要受气候变率增大的影响,逐日气温变率对其影响不大。  相似文献   
126.
Three-dimensional electron density distributions in the solar corona are reconstructed for 100 Carrington rotations (CR 2054?–?2153) during 2007/03?–?2014/08 using the spherically symmetric method from polarized white-light observations with the inner coronagraph (COR1) onboard the twin Solar Terrestrial Relations Observatory (STEREO). These three-dimensional electron density distributions are validated by comparison with similar density models derived using other methods such as tomography and a magnetohydrodynamics (MHD) model as well as using data from the Solar and Heliospheric Observatory (SOHO)/Large Angle and Spectrometric Coronagraph (LASCO)-C2. Uncertainties in the estimated total mass of the global corona are analyzed based on differences between the density distributions for COR1-A and -B. Long-term variations of coronal activity in terms of the global and hemispheric average electron densities (equivalent to the total coronal mass) reveal a hemispheric asymmetry during the rising phase of Solar Cycle 24, with the northern hemisphere leading the southern hemisphere by a phase shift of 7?–?9 months. Using 14 CR (\(\approx13\)-month) running averages, the amplitudes of the variation in average electron density between Cycle 24 maximum and Cycle 23/24 minimum (called the modulation factors) are found to be in the range of 1.6?–?4.3. These modulation factors are latitudinally dependent, being largest in polar regions and smallest in the equatorial region. These modulation factors also show a hemispheric asymmetry: they are somewhat larger in the southern hemisphere. The wavelet analysis shows that the short-term quasi-periodic oscillations during the rising and maximum phases of Cycle 24 have a dominant period of 7?–?8 months. In addition, it is found that the radial distribution of the mean electron density for streamers at Cycle 24 maximum is only slightly larger (by \(\approx30\%\)) than at cycle minimum.  相似文献   
127.
本文论述了跨越断层埋地管线地震反应研究工作概况,包括理论研究和实验研究的进展,并介绍了不同情况下采用的研究方法和建立的相应的研究模型,通过对数据结果进行整理分析,得出跨越断层埋地管线地震反应规律。同时,本文还对埋地管线研究中的一些重要参数对研究结果的影响作了详尽的阐述,提出了需进一步研究的问题和今后可能的研究发展方向。  相似文献   
128.
某盐井施工时,在245.00—270.00m孔段有25m钻具被水泥固结,进行透孔作业时,扫至孔深250.60m时,扫孔用岩心管被扫落的钻杆接头碎块卡住拧断,透孔时发现孔内遗留3.2m断岩心管、钻头等物。根据钻孔结构与遗留钻具的特点.自行设计一种主要由活塞柱、割刀片和复位弹簧组成的小口径割管器,将水泥固结钻具割断,并将钻具和多种残留管材打捞出孔。从割断后打捞上来的钻杆分析,钻杆切割面光滑、平整,钻杆被完全切透,说明此种割管器设计合理,各部件动作有效。  相似文献   
129.
哈陇休玛钼多金属矿床是东昆仑成矿带东段目前仅有的中型斑岩型矿床。为了查明其成矿流体性质及成矿物质来源,构建矿床成矿模式,本文进行了详细的流体包裹体和H-O-S同位素研究。流体包裹体显微测温显示,哈陇休玛矿床发育气液两相和含CO2三相两种类型包裹体,成矿流体呈现中高温(集中于280~340℃)、高盐度(w(NaCl),集中于6.00%~18.00%)和中等密度(集中于0.64~0.92 g/cm3)特点,成矿深度为2.4~4.1 km,形成于中浅成环境。H-O同位素显示,成矿流体具有岩浆水和大气降水混合的特征,但主体以岩浆水为主;S同位素显示,成矿物质主要来自于深部岩浆。结合区域构造演化认为,哈陇休玛矿床成矿模式为印支晚期东昆仑地区发生强烈壳幔混合作用,形成富含成矿元素的混合岩浆,含矿流体在随混合岩浆上升的过程中发生流体沸腾,并与大气降水混合冷却,导致成矿物理化学条件发生变化,促使成矿物质沉淀成矿。  相似文献   
130.
A lightweight unmanned aerial vehicle (UAV) and a tethered balloon platform were jointly used to investigate three-dimensional distributions of ozone and PM2.5 concentrations within the lower troposphere (1000 m) at a localized coastal area in Shanghai, China. Eight tethered balloon soundings and three UAV flights were conducted on May 25, 2016. Generalized additive models (GAMs) were used to quantitatively describe the relationships between air pollutants and other obtained parameters. Field observations showed that large variations were captured both in the vertical and horizontal distributions of ozone and PM2.5 concentrations. Significant stratified layers of ozone and PM2.5 concentrations as well as wind directions were observed throughout the day. Estimated bulk Richardson numbers indicate that the vertical mixing of air masses within the lower troposphere were heavily suppressed throughout the day, leading to much higher concentrations of ozone and PM2.5 in the planetary boundary layer (PBL). The NO and NO2 concentrations in the experimental field were much lower than that in the urban area of Shanghai and demonstrated totally different vertical distribution patterns from that of ozone and PM2.5. This indicates that aged air masses of different sources were transported to the experimental field at different heights. Results derived from the GAMs showed that the aggregate impact of the selected variables for the vertical variations can explain 94.3% of the variance in ozone and 94.5% in PM2.5. Air temperature, relative humidity and atmospheric pressure had the strongest effects on the variations of ozone and PM2.5. As for the horizontal variations, the GAMs can explain 56.3% of the variance in ozone and 57.6% in PM2.5. The strongest effect on ozone was related to air temperature, while PM2.5 was related to relative humidity. The output of GAMs also implied that fine aerosol particles were in the stage of growth in the experimental field, which is different from ozone (aged air parcels of ozone). Geographical parameters influenced the horizontal variations of ozone and PM2.5 concentrations by changing underlying surface types. The differences of thermodynamic properties between land and sea resulted in quick changes of PBL height, air temperature and dew point over the coastal area, which was linked to the extent of vertical mixing at different locations. The results of GAMs can be used to analyze the sources and formation mechanisms of ozone and PM2.5 pollutions at a localized area.  相似文献   
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