Relation between temperature changes of the mid-upper troposphere over Eurasian mid-high latitudes and solar irradiance in the twentieth century

The δ¹⁸O data obtained from an 18.7 m ice core drilled in Chongce Ice Cap at an elevation of 6,530 m a.s.l. in the West Kunlun Mountains on the northern Tibetan Plateau show a strong correlation with the summer temperature of the middle to upper troposphere over the mid-high latitudes of Eurasia. Based on this, the δ¹⁸O record can be used as a proxy of the June–September mean temperature of the mid-upper troposphere (MUT) from 1903 to 1992. The time span of the ice core record is much longer than the meteorological data available only after 1948. Using the empirical mode decomposition method (EMD), the δ¹⁸O record is decomposed into various frequency components and compared with the solar irradiance variations of the same period. The results show that (1) The June–September mean temperature of the MUT over Eurasian mid-high latitudes is completely decomposed into four IMF (intrinsic mode function) components and an increasing trend. (2) Solar irradiance is decomposed into the Schwabe cycle, the Hale cycle, the Gleissberg cycle, and an increasing trend. (3) The correlation coefficients between the June and September mean temperatures of the MUT over Eurasian mid-high latitudes and solar irradiance on the longer timescales (at least more than 11-year) show the significant correlations; their phase changes are basically identical in general, and (4) the 11-year Schwabe cycle exists in the June–September mean temperature of the MUT over Eurasian mid-high latitudes during most of the time from 1903 to 1992, and only in the two high-temperature phases (1929–1944 and from 1975 to the present) may global warming disturb this relation. A full understanding of this phenomenon would shed insight into the potential consequence of global warming on the MUT.     

The hydrothermal karstification and its effect on Ordovician carbonate reservoir in Tazhong uplift of Tarim Basin,Northwest China

With a detailed study on petrology, mineralogy and geochemistry of some important Ordovician carbonate well core samples in Tazhong uplift of Tarim Basin, the distinguishing symbols of hydrothermal karstification are first put forward as the phenomena of rock hot depigmentation, hot cataclasm and the appearance of typical hydrothermal minerals such as fluorite, barite, pyrite, quartz and sphalerite. The main homogenization temperatures of primary fluid inclusions in fluorite are from 260 to 310°C, indicating the temperature of hydrothermal fluid. The fluid affected the dissolved rocks and showed typical geochemistry features with low contents of Na and Mg, and high contents of Fe, Mn and Si. The ratio of ³He/⁴He is 0.02R _a, indicating the fluid from the typical continental crust. The hydrothermal fluid karstification pattern may be described as follows: the hot fluid is from the Permian magma, containing dissolving ingredients of CO₂ and H₂S, and shifts along fault, ruptures and unconformity, and dissolves the surrounding carbonates while it flows. The mechanism of hydrothermal karstification is that the mixture of two or more fluids, which have different ion intensity and pH values, becomes a new unsaturated fluid to carbonates. The hydrothermal karstification is an important process to form hypo-dissolved pinholes in Ordovician carbonates of Tazhong uplift of Tarim Basin, and the forming of hydrothermal minerals also has favorable influence on carbonate reservoirs.

     

GIS工作流系统的长事务处理研究

分析了Sagas事务模型及空间数据版本树技术,设计了一种灵活的长事务补偿控制方案,为集成GIS,MIS及OA的工作流系统提供了有力的事务处理技术支持。     

Dynamic Response and Mechanical Behaviours of Geogrid for High Earth-rockfill Dams

Geotechnical and Geological Engineering - Due to the complexity of the interaction between the geogrid and the soil interface in high earth-rock dams, the method of replacing the grid with steel...     

内蒙古地区场地响应区域特征分析

本文以内蒙古地区台站分布、地质构造和地震活动性为基础,将内蒙古的大部地区划分为三个研究区域分别进行了场地响应研究。对近几年积累的大量ML≥3.0级以上地震,共计39个台站记录到的124次地震事件的785条波形,根据S波的观测振幅谱,采用遗传算法分别反演了三个区域的介质非弹性衰减系数和台站场地响应,并对其进行了讨论。本文得到的介质衰减模型和台站场地响应,将对台网测定ML震级需要考虑的量规函数、台站校正值等提供重要参考。研究结果表明:除个别台站存在场地放大或缩小的响应外,绝大多数台站的场地响应表现出一定的区域性特征;西部区域(除极个别台站外)对高频存在明显衰减;中东部区域对整个频段的反映都比较稳定;东部区域对整个频段存在明显放大,这与该区域覆盖层厚度大相吻合。     

邻近算法在微地震震源位置和一维速度模型同时反演中的应用

微地震事件的空间分布可以用来监测水力压裂过程中裂缝的发育情况.因此,震源定位是微震监测中重要的环节.震源定位依赖准确的速度模型,而震源位置和速度模型的耦合易导致线性迭代的同时反演方法陷入局部极小值.邻近算法作为一种非线性全局优化算法,能够最大程度地避免陷入局部最优解.本文将邻近算法应用于单井监测的微震定位和一维速度模型...     

太行山东麓滹沱河出山处新生代沉积相与地貌结构

研究区在大地构造上处于山西台背斜上的五台隆起与辽冀台向斜内的博野拗陷之间的过渡地区,在地貌上位于太行山地与华北大平原之间的过渡带、滹沱河及其主要(右岸)支流冶河出山口地区,是一片点缀有残山的宽广的山前夷平面与冲洪积扇。     

新疆喀拉通克铜镍矿贵金属矿物定量研究

喀拉通克铜镍矿床产于漏斗状基性岩体中下部的橄榄苏长辉长岩相中,矿石类型分特富铜镍矿石(Ⅰ)、富铜贫镍矿石(Ⅱ)、贫铜贫镍矿石(Ⅲ)及富镍富铜矿石(Ⅳ).由于矿床物质成分复杂特别是金银铂钯矿物颗粒细、品位低、种类多,故首先在进行矿物定性研究的基础上,确定目的矿物的特殊富集流程.然后在人工重砂大样中富集目的矿物,并制成砂光薄片,有代表性的排定视域,引入电子探针-图象分析-计算机联机定量并辅以显微镜定量的综合方法对贵金属元素和矿物进行定量.联机方法是用电子探针以扫描方式提供颗粒电子象和元素X射线面分布象信号给出元素或共存元素的化学信息,对矿物颗粒进行分类,统计出个数及面积百分比.这种方法对微细杂矿物的定量工作颇有成效.     

Machine learning reveals the influences of grain morphology on grain crushing strength

Acta Geotechnica - Grain morphology has significant impacts on the mechanical behaviors of granular materials. However, its influences on grain breakage are still poorly understood due to the...     

青海某地第三系红色碎屑岩层中金异常特征及成因探讨

对青海某地第三系红色碎屑岩层中的金异常特征进行了综述,指出金异常主要存在于第三系中段岩层中,异常在水系沉积物中强度最大,并认为金异常由次生富集作用形成.