Spatio‐temporal tracer variability in the glacier melt end‐member — How does it affect hydrograph separation results?          下载免费PDF全文

Jan Schmieder  Jakob Garvelmann  Thomas Marke  Ulrich Strasser 《水文研究》2018,32(12):1828-1843

Geochemical and isotopic tracers were often used in mixing models to estimate glacier melt contributions to streamflow, whereas the spatio‐temporal variability in the glacier melt tracer signature and its influence on tracer‐based hydrograph separation results received less attention. We present novel tracer data from a high‐elevation catchment (17 km², glacierized area: 34%) in the Oetztal Alps (Austria) and investigated the spatial, as well as the subdaily to monthly tracer variability of supraglacial meltwater and the temporal tracer variability of winter baseflow to infer groundwater dynamics. The streamflow tracer variability during winter baseflow conditions was small, and the glacier melt tracer variation was higher, especially at the end of the ablation period. We applied a three‐component mixing model with electrical conductivity and oxygen‐18. Hydrograph separation (groundwater, glacier melt, and rain) was performed for 6 single glacier melt‐induced days (i.e., 6 events) during the ablation period 2016 (July to September). Median fractions (±uncertainty) of groundwater, glacier melt, and rain for the events were estimated at 49±2%, 35±11%, and 16±11%, respectively. Minimum and maximum glacier melt fractions at the subdaily scale ranged between 2±5% and 76±11%, respectively. A sensitivity analysis showed that the intraseasonal glacier melt tracer variability had a marked effect on the estimated glacier melt contribution during events with large glacier melt fractions of streamflow. Intra‐daily and spatial variation of the glacier melt tracer signature played a negligible role in applying the mixing model. The results of this study (a) show the necessity to apply a multiple sampling approach in order to characterize the glacier melt end‐member and (b) reveal the importance of groundwater and rainfall–runoff dynamics in catchments with a glacial flow regime.  相似文献   

圆钢管约束高强灌浆料局部承压性能研究          下载免费PDF全文

张啸驰  陈建伟  闫文赏  郑玲玲 《地震工程学报》2018,40(3):612-618

以圆钢管约束高强灌浆料局部承压性能试验为基础,基于ABAQUS有限元计算平台,通过建立分段模型(Multi-section Model简称MSM模型)进行数值模拟,探究圆钢管约束高强灌浆料在局部承压作用下的力学性能,并将软件计算得到的荷载-位移曲线与试验结果进行对比分析。结果表明,分段模型适用于圆钢管约束高强灌浆料局部承压作用下的数值模拟,且计算结果与试验结果吻合较好;增大试件高径比、钢管壁厚和高强灌浆料强度均可提高其极限承载力。  相似文献   

舟山冬季暴雨的特征   总被引：1，自引：0，他引：1  

王雷 《海洋预报》2004,21(3):70-75

文章分析了冬季暴雨发生时的环流形势和物理量场分布特征,揭示了冬季暴雨的发生与厄尔尼诺现象有着一定的相关。同时,分析了单站要素的变化,为以后的冬季暴雨预报提供参考。  相似文献   

影响我国热带气旋活动的气候特征及其与太平洋海温的关系   总被引：12，自引：13，他引：12  

林惠娟  张耀存 《热带气象学报》2004,20(2):218-224

基于小波包分解重构方法，利用NCEP／NCAR逐丑再分析资料，讨论了南亚夏季风与季内西太平洋副高活动的关系，提出和定义了用以诊断副高活动的夏季风频域能量判据。诊断结果除佐证了副高已有的一些研究结果和变化规律外，还揭示出副高与季风间一些新的关系特征。  相似文献   

Discussion on research advances and hot issues in diagenesis of clastic-rock reservoirs          下载免费PDF全文

Luo Jing-Lan  Li Chi  Lei Chuan  Cao Jiang-Jun  Song Kun-Peng 《古地理学报》2021,22(6):1021-1040

The research on diagenesis of clastic-rock reservoir is developing rapidly in recent ten years. Thus, it is of great significance in academic and scientific exploration to summarize the domestic and international research progress and the key issues of frontier research on diagenesis. The research progress, main achievement and recognition in diagenesis of clastic-rock reservoirs in recent years is discussed, and the hot issues or developing trend of diagenesis in the future is probed in this paper, on the basis of summarizing the previous research results and understanding, combined with the typical research examples at home and abroad. It is believed that great progress was obtained in provenance and parent rock constraints on sandstone types and their diagenetic evolution pathways, impact of fluid-rock interaction and its product on diagenesis, influence of thermodynamics and overpressure background on diagenesis and pore development, the timing sequence between hydrocarbon accumulation and filling process and the sandstone reservoir becoming low permeability-densification. At present, diagenetic research is developing in direction of the spatial and temporal dynamics and quantitative evolution mechanistic and diagenetic system controlled by the basin fluid dynamics, thermal dynamic processes, combining the micro-scale diagenesis research with the basin macroscopic background such as sedimentation from the source to the basin, burial history, hydrocarbon maturity and charge into reservoirs, tectonic evolution and fluid activity, and fluid and rock interaction.The aim of this paper is to induce the academic peers and experts in diagenesis and the related research fields to come forward with their valuable contributions, to cooperate and work together and joint efforts on the research exquisite, profundity and breadth of diagenesis, and application of the most advanced analytical measurement techniques and methods, as well as integration and infiltration of multidisciplinary, in order to promote the course of the clastic-rock reservoir diagenetic research in China.  相似文献   

王家官庄旧村改造基坑支护设计与施工实践          下载免费PDF全文

李先经  王会军  刘心起 《探矿工程》2020,47(1):69-74

介绍了青岛市即墨区王家官庄旧村改造项目基坑支护设计方案与基坑支护实施情况,该工程地层条件复杂,地下水丰富,又靠近石鹏水库,环境条件较复杂,通过采用土钉墙与高压旋喷桩止水帷幕,基坑降水等技术措施的顺利实施,基坑支护效果良好,确保了地下车库基坑开挖、基础施工的安全,施工质量满足相关技术要求。  相似文献   

CMD180T型钻机在尚义地热井施工中的应用          下载免费PDF全文

王雷浩  李光宏  石逊  殷邈 《探矿工程》2020,47(1):58-61

经物探分析在河北省张家口尚义县大青沟镇南海子村东南1.0 km存在深部断裂构造,为了寻找开发坝上地区地热资源,决定在该位置施工一口2000 m深地热井,即穿过该断裂构造寻找导水通道,完成地热井施工任务。施工中采用了CMD180T型钻机,该钻机采用了先进的全液压传动系统,自动化程度高,性能优异,可大大降低操作人员的劳动强度且易于搬迁、易于操作。其优势在这次地热井工程施工过程中得到了充分的体现。  相似文献   

高效钻杆润滑脂研制及其在川藏铁路勘察中的应用          下载免费PDF全文

熊正强  陶士先  张德龙  邹志飞 《探矿工程》2020,47(11):7-11

针对地质钻探深孔或水平孔失返性漏失时钻具磨损及钻进效率低的问题,以白油、钠基稠化剂与粘结性材料等为原料,采用一步法研制了一种高效钻杆润滑脂,并在川藏铁路昌都段定测勘察水平孔现场应用中取得显著效果,有力支撑服务了川藏铁路大位移水平孔施工。室内评价及现场应用结果表明,该润滑脂具有耐低温（-16 ℃）、易涂抹、良好的粘附性与润滑性以及高性价比特点,能长时间保护钻具,而且其润滑效果与国外同类产品相当。  相似文献   

重庆市中梁山地区隐伏塌陷特征及物探勘测的思路     

张银松  曹聪  康世海  刘家富 《中国岩溶》2020,39(6):918-927

为查明隐伏塌陷区域,分析重庆市中梁山地区岩溶塌陷的特征,发现塌陷主要发生在以岩溶裂隙发育为主的松散粉质黏土区域;地震映像法能方便、快速地查清土层的松散状态,而高密度电阻率法通过正演模拟发现只能探测出2～3倍电极距的异常范围,但能反映出岩溶裂隙发育的漏斗形态,即只要能找出岩溶裂隙的大致位置和浅表松散土层的范围就能圈定隐伏塌陷的区域。对中梁山地区某居民点进行野外勘测,综合以上两种方法圈定隐伏塌陷区域,其推断结果与钻探资料十分吻合,说明这种隐伏岩溶探测思路是可行的。   相似文献   

考虑洞室岩体应力型破坏特征的局部地应力反演方法及应用     

裴书锋  赵金帅  于怀昌  刘国锋  夏跃林  张頔  徐进鹏 《岩土力学》2020,41(12):4093-4104

介绍了一种考虑地下洞室片帮、钻孔剥落等岩体应力型破坏特征为信息源,通过数值模拟智能反演方法预测高应力大型地下洞室群围岩局部应力场的新思路。该方法将地下洞室群片帮、钻孔剥落等应力型破坏的位置、深度或者宽度进行定量描述,以弹性模型计算获得的常偏应力大于岩体启裂强度的范围来表示应力型破坏范围,通过分析实测地应力数据约束部分地应力数量,然后采用智能数值反演方法得到其他的地应力分量。采用该方法预测了白鹤滩水电站右岸地下厂房0+76断面附近围岩地应力场,反演获得最大主应力在34 MPa左右。通过其他部位岩体破裂的数值模拟和观测结果对比,验证了地应力场预测的合理性。  相似文献