巴丹吉林高大沙山表层孔隙水现象的疑义

1997-2003年对巴丹吉林沙漠中不同位置共7个高大沙山和1个流动沙丘表层2m内的孔隙水情况用常规方法作了观测,每年均在相近日期进行。孔隙水量随深度而增大,历年观测期间2m附近的体积含水量约3%,达到相应实测最大持水量的约65%或更高,25cm至1m孔隙水δ18O的正值表明它经过了反复补给-蒸发过程。观测了雨后入渗深度及其在沙丘120m坡面上的分布,另由历年短期能量平衡测验获得沙山陆面蒸发和凝结概念。认为当地年降水量和凝结量不足以对沙山2m表层内的孔隙水现象作出解释,疑另有与大尺度地下水系统相关的补给源。     

河西走廊盆地地下水的氦同位素指示

详细讨论了河西走廊的张掖、永昌和武威盆地地下水中同位素3He/4He、4He/20Ne和δ13C的组成与分布特征。结果表明,泉水溢出地表后尽管受大气不同程度的混染,其中仍含有明显的深源氦气的组分,包括放射性元素铀和钍的蜕变及锂诱发的核反应生成的壳源4He与地球形成初期储存于地幔中的原始3He。这些氦气挥发份随NNE和WNW向活动断裂带向上迁移,直至被循环的地下水带至地表。     

西秦岭武山E-MORB型蛇绿岩及相关火山岩地球化学

西秦岭武山地区发育一套镁铁质-超镁铁质岩石组合,主要出露于鸳鸯镇、李家河、鲁班沟、高家河等地区,呈多个构造岩片逆冲侵位于武山-唐藏断裂带中,主要由变质橄榄岩、辉长岩和玄武岩组成.变质橄榄岩具有高SiO2、高MgO,低ΣREE等特征,球粒陨石标准化的REE配分型式类似于大洋中脊变质橄榄岩特征;鸳鸯镇、李家河、鲁班沟玄武岩主体以相对高TiO2、低Al2O3,Na2O>>K2O,REE平坦或LREE轻微富集,以及HFSE不分异为特征,总体具有E-MORB地球化学特征;而高家河玄武岩则具有岛弧火山岩地球化学性状.综合区域地质、岩石学和地球化学研究认为,武山的镁铁质-超镁铁质岩石组合主体属于构造肢解的E-MORB型蛇绿岩,形成于古洋盆初始裂解阶段的洋中脊构造环境.在区域构造地质对比、年代学研究基础上,认为武山的E-MORB型蛇绿岩代表了秦岭早古生代古洋盆岩石圈残片,其与以高家河玄武岩为代表的岛弧火山岩共同构成蛇绿混杂岩,标定了秦岭早古生代古洋盆闭合后的缝合线.     

模糊聚类方法研究堤坝渗漏

稳定同位素、水化学的方法是研究堤防渗漏是一种十分有效的方法,以往人们大多只是定性的分析判断。结合北江大堤工程实例,尝试应用模糊聚类方法,选取22个水样稳定同位素和水化学值作为指标特征值,并赋与不同的权重,进行模糊聚类分析,聚类结果表明,T12孔和T9孔北5 m处涌水、江水和T9孔北排水沟出水在稳定同位素和水化学成分的Cl-及TDS上表现出了较大的相关性,可能为同一补给来源,为堤坝渗漏通道的判断提供了佐证。     

静电纺丝技术制备纳米纤维复合环氧涂层及其海洋防腐性能

纳米纤维可以填补有机涂层中存在的孔隙和微裂纹，并提高其抗腐蚀能力。本文介绍了一种利用静电纺丝方法在Q235碳钢表面制备纳米纤维，并与有机环氧树脂复合，进而提高树脂防腐性能的技术。制备了环氧-纤维复合涂层（PAN-NFs/EP），采用电化学方法以及盐雾实验对复合涂层的防腐性能进行了表征，结果表明嵌入了纳米纤维的环氧复合涂层，其电化学阻抗提高了两个数量级，防腐性能明显提高。本研究对静电纺丝技术在海洋防腐中的应用具有一定的参考价值。     

The IOD-ENSO precursory teleconnection over the tropical Indo-Pacific Ocean: dynamics and long-term trends under global warming

The dynamics of the teleconnection between the Indian Ocean Dipole(IOD) in the tropical Indian Ocean and El Ni?o-Southern Oscillation(ENSO) in the tropical Pacific Ocean at the time lag of one year are investigated using lag correlations between the oceanic anomalies in the southeastern tropical Indian Ocean in fall and those in the tropical Indo-Pacific Ocean in the following winter-fall seasons in the observations and in high-resolution global ocean model simulations. The lag correlations suggest that the IOD-forced interannual transport anomalies of the Indonesian Throughflow generate thermocline anomalies in the western equatorial Pacific Ocean, which propagate to the east to induce ocean-atmosphere coupled evolution leading to ENSO. In comparison, lag correlations between the surface zonal wind anomalies over the western equatorial Pacific in fall and the Indo-Pacific oceanic anomalies at time lags longer than a season are all insignificant, suggesting the short memory of the atmospheric bridge. A linear continuously stratified model is used to investigate the dynamics of the oceanic connection between the tropical Indian and Pacific Oceans. The experiments suggest that interannual equatorial Kelvin waves from the Indian Ocean propagate into the equatorial Pacific Ocean through the Makassar Strait and the eastern Indonesian seas with a penetration rate of about 10%–15% depending on the baroclinic modes. The IOD-ENSO teleconnection is found to get stronger in the past century or so. Diagnoses of the CMIP5 model simulations suggest that the increased teleconnection is associated with decreased Indonesian Throughflow transports in the recent century, which is found sensitive to the global warming forcing.The dynamics of the teleconnection between the Indian Ocean Dipole(IOD)in the tropical Indian Ocean and El Ni?o-Southern Oscillation(ENSO)in the tropical Pacific Ocean at the time lag of one year are investigated using lag correlations between the oceanic anomalies in the southeastern tropical Indian Ocean in fall and those in the tropical Indo-Pacific Ocean in the following winter-fall seasons in the observations and in high-resolution global ocean model simulations.The lag correlations suggest that the IOD-forced interannual transport anomalies of the Indonesian Throughflow generate thermocline anomalies in the western equatorial Pacific Ocean,which propagate to the east to induce ocean-atmosphere coupled evolution leading to ENSO.In comparison,lag correlations between the surface zonal wind anomalies over the western equatorial Pacific in fall and the Indo-Pacific oceanic anomalies at time lags longer than a season are all insignificant,suggesting the short memory of the atmospheric bridge.A linear continuously stratified model is used to investigate the dynamics of the oceanic connection between the tropical Indian and Pacific Oceans.The experiments suggest that interannual equatorial Kelvin waves from the Indian Ocean propagate into the equatorial Pacific Ocean through the Makassar Strait and the eastern Indonesian seas with a penetration rate of about 10%–15%depending on the baroclinic modes.The IOD-ENSO teleconnection is found to get stronger in the past century or so.Diagnoses of the CMIP5 model simulations suggest that the increased teleconnection is associated with decreased Indonesian Throughflow transports in the recent century,which is found sensitive to the global warming forcing.     

Possible causes for the persistence barrier of SSTA in the South China Sea and the vicinity of Indonesia

The persistence barrier refers to the lag correlation of sea surface temperature anomalies (SSTA) showing a rapid and significant decline in a specific season, regardless of the starting month. This implies that there is a decrease in forecast skill for SSTA in this specific season. This paper investigates the possible causes for the persistence barrier of SSTA in the South China Sea (SCS) and its adjacent regions from the perspective of interannual-interdecadal time scales. The results show that the persistence barrier of SSTA exists not only in the SCS, but also in the vicinity of Indonesia south of the equator. The SCS barrier occurs around October--November, while the occurrence of the barrier in the Indonesia region is around November--December. For these two regions, the occurrence of the persistence barrier is closely associated with the interdecadal variability of SSTA, as well as the interannual variability. The persistence barriers in the SCS and the Indonesia region do not exist alone if the interdecadal variability is not considered, because SSTA have a short memory of less than 4 months, regardless of the starting month. Moreover, the influence of the interdecadal variability of SSTA on the persistence barrier of SSTA in the SCS and the Indonesia region may be associated with SSTA in the Indian Ocean and the western Pacific, but is not closely associated with the Pacific Decadal Oscillation. However, compared with the spring persistence barrier (SPB) of ENSO, the close relationship between the persistence barriers in the SCS and the Indonesia region and the interdecadal variability is unique, since the ENSO SPB is not significantly affected by such variability. In addition, although the persistence barriers in both the SCS and the Indonesia region are quite obvious in strong ENSO cases, the interdecadal variability of SSTA also plays a non-negligible role in this relationship.     

青岛汇泉湾海滩粒度变化原因分析及保护建议

文章以青岛汇泉湾为例,分析了汇泉湾海滩砂粒粗化的原因,并就如何保护好海滩旅游资源提出一些建议.