2002年3月31日台湾M 7.5地震概述

2002年3月31日在台湾以东沿海附近发生里氏7.5级地震，造成生命和财产的较严重损失。文章概述了这次地震的情况，包括震源参数、震源机制解、破坏、伤亡和发震背景。     

Elastic properties of sands,Part 1: Micro computed tomography image analysis of grain shapes and their relationship with microstructure

Elastic properties of an unconsolidated sand are largely dependent on the elastic properties of its constituent grain and the micro-structure that defines how the grains are arranged within themselves. Coordination number, that is the average number of contacts a grain has with its neighbours, and contact surface area are the two parameters closely related to the microstructure. Moreover, grain shapes and sorting also have substantial influence on these parameters. To calculate these parameters and find any potential relationships with the shape factors, we acquire high-resolution micro computed tomography images of four mechanically compacted unconsolidated dry sand samples that are of different shape factors and sorting indices. After a comprehensive voxel-based data processing, we calculate shape factors such as sphericity and roundness of each grain in all samples. Using own algorithm, we then calculate the coordination number and contact surface area. Results show that samples of well-sorted and higher spherical and rounded grains have higher coordination number and contact surface area than the samples of poorly sorted and lower spherical and rounded grains. Among the poorly sorted samples, coordination number is largely dependent on the fraction of larger grain sizes present in the sample. Inside any given sample, grains of lower sphericity tend to have higher coordination numbers. Moreover, more spherical and rounded grains have greater contact surface area with their neighbours.     

Quantification and characterization of condensed organic matter in sediments from the Pearl River Delta and Estuary, South China

Nonhydrolyzable carbon （NHC） and black carbon （BC） were measured upon treatments with the HCl/HF/trifluoroacetic acid method, and with the combustion method at 375 ℃, respectively in three contaminated soils from the urban area of Guangzhou and twenty-two bulk and size-fractionated sediments from the Pearl River Delta and Estuary, China. The isolated NHC and BC fractions were also characterized using elementary analysis, radiocarbon accelerated mass spectroscopy （AMS）, solid state ^13C cross-polarization and magic angle spinning unclear magnetic resonance spectroscopy （^13C-CP/MAS NMR）, Fourier transformed infrared spectroscopy （FTIR）, and Raman microspectrometry. The results showed that the NHC and BC accounted for 25.6%-84.7 % and 4.14%-17.3%, respectively, of the total organic carbon （OC） with averages of 51.9% and 11.2% in the soils and sediments. For the less contaminated, low OC fiver and estuary sediments （WR and C08）, the OC and NHC concentrations increased with decreasing particle size.     

Charred forests accelerate snow albedo decay: parameterizing the post‐fire radiative forcing on snow for three years following fire

As large, high‐severity forest fires increase and snowpacks become more vulnerable to climate change across the western USA, it is important to understand post‐fire disturbance impacts on snow hydrology. Here, we examine, quantify, parameterize, model, and assess the post‐fire radiative forcing effects on snow to improve hydrologic modelling of snow‐dominated watersheds having experienced severe forest fires. Following a 2011 high‐severity forest fire in the Oregon Cascades, we measured snow albedo, monitored snow, and micrometeorological conditions, sampled snow surface debris, and modelled snowpack energy and mass balance in adjacent burned forest (BF) and unburned forest sites. For three winters following the fire, charred debris in the BF reduced snow albedo, accelerated snow albedo decay, and increased snowmelt rates thereby advancing the date of snow disappearance compared with the unburned forest. We demonstrate a new parameterization of post‐fire snow albedo as a function of days‐since‐snowfall and net snowpack energy balance using an empirically based exponential decay function. Incorporating our new post‐fire snow albedo decay parameterization in a spatially distributed energy and mass balance snow model, we show significantly improved predictions of snow cover duration and spatial variability of snow water equivalent across the BF, particularly during the late snowmelt period. Field measurements, snow model results, and remote sensing data demonstrate that charred forests increase the radiative forcing to snow and advance the timing of snow disappearance for several years following fire. Copyright © 2016 John Wiley & Sons, Ltd.     

中尺度模式积云参数化方案的改进及其在暴雨模拟中的应用

本文针对中国暴雨发生发展天气特征,改进和发展了一种适合于描述东亚暴雨的中尺度积云参数化方案.首先基于近年来(1990—2010)江淮流域汛期降水合成分析的基础上,诊断出组织化对流降水环境的动力参数;其次利用该动力参数作为动力控制条件,改进了Kain-Fritsch Eta中尺度积云对流参数化方案;最后利用改进的中尺度积云参数化方案对梅雨期暴雨、华南前汛期暴雨过程进行了数值模拟,结果表明:改进后的中尺度积云参数化方案对上述两次暴雨过程的落区及强度的模拟,均有明显改进.     

格点大气环流模式GAMIL2参数不确定性的量化分析与优化

物理过程参数化方案的不确定性是目前气候系统模式不确定性的重要来源之一.随着模式内在复杂度攀升,模拟场景多样化,参数化方案中基于先验的和人工的物理参数选取方法已经逐步成为限制模式模拟能力的瓶颈之一.为此,本文设计并提出了初选与寻优相结合的两步法参数优化方案.初选阶段用全因子采样方法对不确定参数空间进行初始敏感性分析,估计最优解所在区域;寻优步采用单纯型下山法,基于初选阶段确定的参数组合快速寻优.将两步法应用于中国科学院大气物理研究所(英文缩写:IAP)大气科学和地球流体力学数值模拟国家重点实验室(英文缩写:LASG)格点大气模式第2版:GAMIL2,选取其深对流方案和云量方案中的3个重要参数开展寻优,优化以综合减小模式降水、风场、温度、湿度、位势高度以及辐射通量的误差为目标.这些变量用GAMIL2标准版本标准化后形成单一的目标. 结果显示,优化后的目标函数值比GAMIL2 标准版本改进了7.5%.机理分析表明,调优后的参数优化了大气中的水汽凝结作用,进而减少模式的湿度偏差,改进云量的模拟效果;同时水汽凝结作用的变化通过大气内部动力和热力相互作用及响应影响温度、位势高度和风场的模拟.     

冀东铁精矿的物化性能测试

对冀东铁精矿进行了系统的物化性能测试。结果表明，铁精矿粒度较粗、颗粒表面光滑、比表面积小、SiO2含量较高。结合矿相结构分析了冀东铁精矿成球性能比较差的原因。采用3％的优质膨润土作铁精矿球团的黏结剂，制得球团的性能能够满足生产要求。     

黑龙江省三江-穆棱河J_2-K_1沉积体系与聚煤模式

研究煤盆地的构造是进行找煤勘查工作的必要基础。本文全面分析了黑龙江省东部三江—穆棱河J2-K1聚煤环境模式及分布特点,为在该区找煤指明了勘查方向和具体目标。     

杨柳井井田水文地质条件分析

通过对井田内各地层及断层带富水性的分析,认为井田主要含水层为松子坎组、茅草铺组、夜郎组玉龙山段、长兴组、龙潭组及茅口组;矿井直接充水水源为长兴组岩溶水、龙潭组裂隙水及茅口组岩溶水,间接充水水源为松子坎组及茅草铺组、夜郎组玉龙山段的岩溶裂隙水;充水通道为岩溶裂隙、采动裂隙和断层破碎带;在断层破碎带附近或煤层与茅口组相接部位,易产生突水,要做好超前探放水工作,保证矿井安全生产。     

藏北羌塘盆地羌资2井中侏罗统布曲组碳酸盐岩岩石学及储集物性特征

本文讨论了羌塘盆地羌资2井中侏罗统布曲组碳酸盐岩岩石学及储集物性特征.碳酸盐岩主要有亮晶鲕粒灰岩、白云岩、泥晶灰岩,以及他们之间的过渡类型;储集空间主要有孔隙与裂缝两种类型,表现为孔隙-裂缝组合.孔隙可分为粒间溶孔、粒内溶孔、晶间孔、晶间溶孔、沿缝合线等分布的溶孔;裂缝可分为构造缝、构造-溶解缝、压溶缝和溶蚀缝.亮晶鲕粒灰岩孔隙度平均值1.084%,渗透率平均值0.0319×10~(-3) μm~2;白云岩孔隙度平均值1.77%,渗透率平均值0.1591×10~(-3) μm~2;储集物性特征均为低孔低渗、高排替压力、微-细喉道、分选中等,不好的负偏态细歪度特征.泥晶灰岩和过渡类型灰岩的储集物性特征与亮晶鲕粒灰岩和白云岩相似.最后,讨论了成岩作用对碳酸盐岩储集物性的影响,并认为成岩作用对储集物性的不利影响明显大于有利影响.