雷暴探测研究的进展

基于达州市2015年10月-2016年9月的闪电定位和探空观测资料,以850 hPa与500 hPa温差、大气可降水量、K指数、对流有效位能、对流抑制和抬升指数作为雷暴预警因子,利用投影寻踪动态聚类方法对该时段内的雷暴个例构建了预警模型。结果表明：（1）模型预报结果定量评估的临界成功指数为72.00%,该模型对个例达到了识别和预警效果;（2）该预警模型与常规预警方法相比,具有识别率高,计算简便,客观性强等特点,可为雷暴预警提供了一种新的客观预报方法。

     

东北典型林区雪深反演算法的验证与分析

积雪对自然环境和人类活动都有极其重要的影响。积雪参数（雪面积、雪深和雪水当量）反演对水文模型和气候变化研究有着实际的意义。然而,目前森林区的雪深遥感反演精度一直有待于进一步提高。东北地区是我国最大的天然林区和重要的季节性积雪区之一,本文利用FY3B卫星微波成像仪（MWRI）L1级亮温数据和L2级雪水当量数据,以及东北典型林区野外实测雪深数据,对Chang算法、NASA 96算法和FY3B雪深业务化反演算法进行了验证与分析。结果表明：在东北典型林区的雪深反演中,Chang算法和NASA 96算法反演的雪深波动都比较大,当森林覆盖度f≤0.6时,NASA 96算法表现比较好,均方根误差值在3种算法中较小,但当f >0.6时,NASA 96算法失真严重。当考虑纯森林像元（f=1）时,Chang算法低估了雪深47%。当f≤0.3时,FY3B业务化算法始终优于Chang算法。整体上,FY3B业务化算法相对稳定,具有较高的精度。     

Modeling of the eddy viscosity by breaking waves

Breaking wave induced nearsurface turbulence has important consequences for many physical and biochemical processes including water column and nutrients mixing,heat and gases exchange across air-sea interface.The energy loss from wave breaking and the bubble plume penetration depth are estimated.As a consequence,the vertical distribution of the turbulent kinetic energy(TKE),the TKE dissipation rate and the eddy viscosity induced by wave breaking are also provided.It is indicated that model results are found to be consistent with the observational evidence that most TKE generated by wave breaking is lost within a depth of a few meters near the sea surface.High turbulence level with intensities of eddy viscosity induced by breaking is nearly four orders larger than υwl(=κuwz),the value predicted for the wall layer scaling close to the surface,where uw is the friction velocity in water,κ with 0.4 is the von Kármán constant,and z is the water depth,and the strength of the eddy viscosity depends both on wind speed and sea state,and decays rapidly through the depth.This leads to the conclusion that the breaking wave induced vertical mixing is mainly limited to the near surface layer,well above the classical values expected from the similarity theory.Deeper down,however,the effects of wave breaking on the vertical mixing become less important.     

Effect of Shale Reservoir Characteristics on Shale Oil Movability in the Lower Third Member of the Shahejie Formation,Zhanhua Sag

To reveal the effect of shale reservoir characteristics on the movability of shale oil and its action mechanism in the lower third member of the Shahejie Formation(Es3l), samples with different features were selected and analyzed using N2 adsorption, high-pressure mercury injection capillary pressure(MICP), nuclear magnetic resonance(NMR), high-speed centrifugation, and displacement image techniques. The results show that shale pore structure characteristics control shale oil movability directly. Movable oil saturation has a positive relationship with pore volume for radius > 2 μm, as larger pores often have higher movable oil saturation, indicating that movable oil is present in relatively larger pores. The main reasons for this are as follows. The relatively smaller pores often have oil-wetting properties because of organic matter, which has an unfavorable effect on the flow of oil, while the relatively larger pores are often wetted by water, which is helpful to shale oil movability. The rich surface provided by the relatively smaller pores is beneficial to the adsorption of immovable oil. Meanwhile, the relatively larger pores create significant pore volume for movable oil. Moreover, the larger pores often have good pore connectivity. Pores and fractures are interconnected to form a complex fracture network, which provides a good permeability channel for shale oil flow. The smaller pores are mostly distributed separately;thus, they are not conducive to the flow of shale oil. The mineral composition and fabric macroscopically affect the movability of shale oil. Calcite plays an active role in shale oil movability by increasing the brittleness of shale and is more likely to form micro-cracks under the same stress background. Clay does not utilize shale oil flow because of its large specific surface area and its block effect. The bedding structure increases the large-scale storage space and improves the connectivity of pores at different scales, which is conducive to the movability of shale oil.     

由空间直角坐标计算大地坐标的简便公式

对大地测量教科书中给出的空间三维直角坐标与大地坐标的转换公式进行了大量的计算与分析，总结得出一组由空间直角坐标计算大地坐标的简便公式。     

岩石嵌固掏挖基础抗拔承载特性及其影响因素研究

岩石嵌固掏挖基础目前已经广泛应用于电力基础工程中。原状土由于受扰动较小,胶结性强,具有良好的抗剪强度,对掏挖基础抗拔承载力具有重要影响,因此研究原状土参数变化对基础上拔承载性能的影响规律具有重要意义。结合现场试验,建立数值模型,研究土体黏聚力、内摩擦角、弹性模量对基础上拔承载性能的影响规律。研究表明:土体内摩擦角和黏聚力对基础抗拔承载力具有较大影响,而弹性模量影响程度较低;参数的变化对土体塑性区发展规律影响较小。     

广西凤凰山银矿床构造控矿与找矿方向研究

广西凤凰山银矿床位于西大明山复式背斜北东端的次级褶皱断裂破碎带中。本文基于区域构造背景,研究了凤凰山银矿床构造对矿化蚀变的控制作用,分析了控矿构造组合样式及其形成机理。认为矿体产于NWW向压剪性断裂中的局部张性地段,断裂产状变化部位以及NWW向断裂与NW向断裂交会部位是成矿有利部位。     

基于密集线性台阵的背景噪声成像在明光市城市活断层调查中的应用

近年来,短周期密集台阵被动源探测技术逐渐成为地壳精细结构探测研究中的重要手段.为了探讨其应用于城市活断层调查在勘探尺度的有效性,在横跨安徽省明光市郯庐断裂带东界两条主干断裂位置,沿同期的主动源S波反射剖面,安徽省地震局和中国科学技术大学联合布设了一条由133个短周期地震仪组成的被动源密集测线.我们通过该被动源测线获得了约28天的连续波形记录,并采用一种新的线性台阵背景噪声成像方法——拓距相移法提取了10 Hz~2.0 s宽频的基阶Rayleigh波相速度频散曲线.利用得到的宽频带频散曲线,我们反演了近地表 1.3 km以浅的高分辨率S波速度结构,并与基本重合的主动源S波反射剖面以及地质资料等进行对比,验证了反演结果的可靠性,同时进一步分析了郯庐断裂带东界两条主干断裂的断层特征.结果表明：（1）被动源与主动源反演结果在近地表100 m以浅高度一致,且被动源的反演深度更深;（2）池河—太湖断裂是隐伏于深部的走滑断裂和浅部伸展断裂的综合反映,浅部为倾向北西的正断层,向上穿透第四系地层,可能为活动断裂;（3）拓距相移法能有效拓宽频散曲线的提取频带,保证浅部结构具有高分辨率,同时大大加强对深部结构的约束.该方法能够获得可靠的地下结构反演结果,可以作为城市活断层调查的一种新的有效手段.

     

震级标度的不一致与震源的复杂性

矩震级标度是从地震矩换算过来的,换算关系中地震应力降与剪切模量估算的不准确会对矩震级标度产生影响.本文利用1976年1月~2006年12月发生在东经75°~135°,北纬15°~55°的M≥5地震的矩震级与面波震级,探讨了应力降与剪切模量的比值Δσ/μ在中国及邻区以及在不同震级下的分布特征.中国大陆及邻区的Δσ/μ值分布较分散,不同地区的Δσ/μ值明显不同,且绝大部分值大于矩震级和地震矩换算关系中使用的全球平均值.对于同一地区不同震级的地震,其Δσ/μ值也不一样,震级大,Δσ/μ值通常也大.研究认为剪切模量和地震应力降的估计对矩震级标度的影响不能忽略.     

高精度磁测在IOCG型铁矿勘查中的应用——以智利英格瓦塞铁矿为例

IOCG型（铁氧化物铜金型）矿床富含铁氧化物,且常缺失硫化物,高精度磁测是寻找IOCG矿床重要的有效手段之一。英格瓦塞铁矿位于智利中北部IOCG型矿床成矿带,前期地质工作程度较低。在智利英格瓦塞铁矿矿区地质特征调查基础上,重点针对中部矿区的7个磁异常区,利用RGIS对其高精度磁测数据进行面积上延、面积下延、剖面下延及2.5D反演拟合处理,结果表明,本区引起磁异常的磁性地质体整体呈NE向延伸、倾向NW、倾角较陡。除Ⅰ号和Ⅴ号磁异常规模较小外,其他几个磁异常中心找矿前景较大,有规模的磁异常区大多埋深在50~120 m之间,为下一步地质找矿钻探验证提供了有效的基础。同时,该勘查方法可为中国IOCG型铁矿找矿工作提供参考依据。