南秦岭金龙山微细浸染型金矿成矿时代

 金龙山金矿带是南秦岭新发现的卡林型金矿带,主要产于上泥盆统南羊山组细碎屑岩—碳酸盐岩建造中,在上泥盆统冷水河组、下石炭统碳酸盐建造中也有产出,可分为明显受断裂控制的脉型金矿化和受有利岩性及小规模断裂、节理控制的浸染型矿化。     

黄土高原表土磁化率与气候要素的定量关系研究

黄土高原地区已建立多个表土低频磁化率-气候转换函数,为黄土古气候定量重建提供了关键方法。但是表土磁化率变化的气候控制因素的系统研究尚未开展; 同时,低频磁化率部分受到沉积作用的影响,需要寻找气候意义更明确的指标。我们系统采集了黄土高原及周边地区的表土样品,运用相关、回归和因子分析等方法,研究了不同气候要素及其季节变化对表土磁化率和频率磁化率的控制作用。结果显示,湿度是控制黄土高原表土磁化率的主要因素,温度的影响相对较小; 降水的季节分配也有影响,月降水变率较小的地区磁化率较高。在此基础上,选择反映成壤磁性颗粒组分的频率磁化率,建立了频率磁化率-年均降水量的转换函数,为黄土古气候定量估算提供了新的途径。     

塔层风廓线与湍流通量关系的理论与实验研究(一)

本文根据大气边界层与湍流力学理论,研究得到了塔层无量纲风梯度与湍流动量通量在中性及不稳定大气层结中均能满足的理论关系——“塔层KEYPS方程”;并将其数值计算结果与实测数据作了对比,验证结果表明:该关系式和实际情况的吻合程度相当好,因而具有一定的实用价值。     

甘肃老虎山闪长岩的地球化学特征及其成因

位于北祁连造山带东端的老虎山闪长岩侵位在晚奥陶统阴沟群砂板岩中,闪长岩的单颗粒锆石Ｕ－Ｐｂ年龄为４２３．５±２．８Ｍａ,是中志留世侵位的。老虎山闪长岩属于钙碱性岩系,富集ＬＲＥＥ和大离子亲石元素（ＬＩＬＥ）,Ｃｅ／Ｙｂ比值大于１３,Ｔｈ／Ｔａ比值大（１３～４２）,在微量元素分布图中呈现明显的Ｎｂ负异常,具岛弧或活动陆缘环境的特征。虽然老虎山闪长岩具有岛弧地球化学特征,但并不能认为它就产于岛弧环境,因为,在奥陶纪末期,早古生代的北祁连洋盆已经发生闭合,华北板块与柴达木板块已发生碰撞。因此,老虎山闪长岩是造山后侵位的,其成因可能与岩石圈拆沉作用有关。     

Mechanisms for the link between onset and duration of open water in the Kara Sea

The sea ice conditions in the Kara Sea have important impacts on Arctic shipping, oil and gas production, and marine environmental changes. In this study, sea ice coverage (CR) less than 30％ is considered as open water, its onset and end dates are defined as Topen and Tclose, respectively. The sea ice melt onset (Tmelt) is defined as the date when ice-sea freshwater flux initially changes from ice into the ocean. Satellite-based sea ice concentration (SIC) from 1989 to 2019 shows a negative correlation between Topen and Tclose (r = –0.77, p < 0.01) in the Kara Sea. This phenomenon is also obtained through analyzing the hindcast simulation from 1994 to 2015 by a coupled ocean and sea-ice model (NAPA1/4). The model results reveal that thermodynamics dominate the sea ice variations, and ice basal melt is greater than the ice surface melt. Heat budget estimation suggests that the heat flux is significant correlated with Topen (r = –0.95, p < 0.01) during the melt period (the duration of multi-year averaged Tmelt to Topen) influenced by the sea ice conditions. Additionally, this heat flux is also suggested to dominate the interannual variation of the heat input during the whole heat absorption process (r = 0.81, p < 0.01). The more heat input during this process leads to later Tclose (r = 0.77, p < 0.01). This is the physical basis of the negative correlation between Topen and Tclose. Therefore, the duration of open water can be predicted by Topen and thence support earlier planning of marine activities.     

A new method of testing pile using dynamic P-S-curve made by amplitude of wave train

A new method of detecting the vertical bearing capacity for single-pile with high strain is discussed in this paper. A heavy hammer or a small type of rocket is used to strike the pile top and the detectors are used to record vibration graphs. An expression of higher degree of strain (deformation force) is introduced. It is testified theoretically that the displacement, velocity and acceleration cannot be obtained by simple integral acceleration and differential velocity when long displacement and high strain exist, namely when the pile phase generates a whole slip relative to the soil body. That is to say that there are non-linear relations between them. It is educed accordingly that the force P and displacement S are calculated from the amplitude of wave train and (dynamic) P-S curve is drew so as to determine the yield points. Further, a method of determining the vertical bearing capacity for single-pile is discussed. A static load test is utilized to check the result of dynamic test and determine the correlative constants of dynamic-static P(Q)-S curve. Foundation item: Key projects of the tenth Five-year Plan of Yunnan Province (documented Yunnan district [2002]54-02-02) and Geophysical Society of Yunnan Province.     

江苏地区渗流方位角变化特征分析

利用谐波振幅和峰谷值2种方法,计算江苏地电台站渗流方位角,并尝试利用渗流方位角进行映震分析,结果表明：①使用2种方法计算的渗流方位角相差不大,由此所得地震对应关系应基本可靠;②高邮地电台渗流方位角与高邮-宝应M_S 4.9地震对应关系较好。因此,对江苏地区开展渗流方位角变化特征分析具有一定意义。     

中国地震网格试验系统中资源管理与作业调度研究-资源管理和作业动态分配模型ProRMJS的建立me

通过分析与研究建立资源管理和作业动态分配ProRMJS模型,解决了中国地震灾害仿真网格试验系统（CEDAGrid）中网格科学计算平台在初期建设中存在的一些资源管理方面的问题. 针对网格科学计算平台默认各个计算节点均能提供计算服务的问题,ProRMJS通过ldquo;计算池rdquo;这一虚拟组织为调度器分发作业提供支撑;而调度器则根据计算池中各个节点的计算能力和状态,动态分配任务,这样就保证了计算平台的稳定性. 针对默认各个计算节点均能完成任务的问题, ProRMJS通过监控各个节点所负担作业的运行进度和设定作业时间阈值来管理作业运行. 对于各个节点计算能力大小的区别, ProRMJS通过对各个节点计算性能的权值量化,实行按ldquo;需rdquo;分配作业. 对各个节点计算性能的权值量化, ProRMJS是通过综合考虑各个因素对机器计算能力大小的影响后通过加权计算的方式完成的,从而提高了整个计算平台的工作效率. 最后通过实现地震应力触发科学计算实例验证了方案的有效性,为网格技术在地震领域内的进一步应用作了有意义的探索.      

多隐层BP神经网络在模式预报中的简化应用

EC细网格预报效果好,基本满足业务需要,在工作中被广泛应用。为进一步提升预报准确性,做好迪士尼园区的气象服务保障,选取2016年7月至2017年6月1年的2 m温度预报场,24 h预报时效的时间分辨率为3 h,72 h预报时效的时间分辨率为24 h,分别用回归分析法、S型和简化Line型BP神经网络法进行模式释用,与迪士尼气象站观测数据对比。结果表明:阈值为1℃时,对模式结果释用后,均方根误差减少了0.5℃到1.0℃,3—9 h和21—72 h预报时效的准确率由原来的50%和30%分别上升到70%和50%。采用S型多隐层BP神经网络误差最小,不同预报时效释用稳定性最高,同时该释用方法对t_(min)的预报特征把握更精准,释用效果明显优于对t_(max)的预报释用,但迭代计算耗费时间大幅增多,与预报效果的提升不成正比。简化Line型的BP神经网络通过8个半月的数据量和简单的网络模式,捕获了EC预报的特征,不但减小了计算量,大幅缩短了计算时间,而且预报结果也有显著提升,预报稳定性较好,具有广泛的业务应用空间。     

黑河中游荒漠绿洲农业适应气候变化技术研究

以我国第二大内陆河流域——黑河流域的中游荒漠绿洲为例,基于长期定位试验成果,研究了绿洲农业适应气候变化的技术及其潜力。结果表明,在田间水平上,垄沟灌溉种植、主栽作物与伴生植物混播种植、优化水肥管理、建立枣粮复合系统是绿洲农业适应气候变化的有效技术;在绿洲水平上,调整农业种植结构、加大农田林网规格和减少农田林网的灌溉次数、降低防风固沙体系中高耗水树种——杨树的比例等技术是应对气候变化的重要途径。综合评价结果表明,在黑河中游绿洲,通过推广上述技术,在不降低绿洲农业产值和不影响绿洲生态系统稳定性的前提下,初步估算每年可节水2.96×108m3,抵消了气温上升大约1℃所带来的蒸散发消耗量。