“Three-Component” Digital Prospecting Method：A New Approach for Mineral Resources Quantitative Prediction and Assessment

“Three-component” method consists of three clase-connected aspects: geological anomaly,diversity of mineralization and mineral deposit spectrum. All these three concepts are not new separately, but it is a new approach to combine these three aspects in one single concept for quantitative mineral resources prediction and assessment and it is also the first time to conduct a more detailed study in each aspect. Investigation and clarification of geological anomalies, diversity of mineralization and spectrum of mineral deposits are realized by digitization and quantification of ore forming controlling factors, oreexisting symbols or marks, characteristics of mineralization and regulation of ore-genesis and laws of distribution. These procedures lead to construction of a “digital model“ for mineral resources prediction andassessment.     

Study on simulating strong ground motion by fractal stochastic method

The time history of strong ground motion can be synthesized by empirical Green's function (EGF) method.Firstly a large seismic event is discretized into a series of subevents; secondly recordings of earthquakes with proper size and spatial distribution are chosen as time history (EGF) of those subevents; finally the EGFs are summated to get the time history of ground motion caused by the large event.     

三峡库区巫山县城新址岩质库岸再造预测

巫山县城新址位于西坪和大宁河两岸.组成该库段的基岩主要为泥岩、粉砂岩、泥灰岩等,岩性较软弱,且地质构造变动强烈,褶皱、断裂发育,岩层破碎,崩塌、滑坡分布较多,库岸再造问题严重;同时,岸坡再造又严重影响着新县城的规划和库岸的防护.因此把稳态坡形类比法应用于巫山县城新址基岩岸坡的再造预测,定量预测库岸的最终再造宽度,以指导新城的规划与建设.     

Homogenization of the Daily Land Surface Temperature over the Mainland of China from 1960 through 2017

Land surface temperature(LST) is one of the most important factors in the land-atmosphere interaction process. Raw measured LSTs may contain biases due to instrument replacement, changes in recording procedures, and other non-climatic factors. This study attempts to reduce the above biases in raw daily measurements and achieves a homogenized daily LST dataset over China using 2360 stations from 1960 through 2017. The high-quality land surface air temperature(LSAT)dataset is used to correct the LST warming biases especially evident during cold months in regions north of 40°N due to the replacement of observation instruments around 2004. Subsequently, the Multiple Analysis of Series for Homogenization(MASH) method is adopted to detect and then adjust the daily observed LST records. In total, 3.68 × 103 effective breakpoints in 1.65 × 106 monthly records(about 20%) are detected. A large number of these effective breakpoints are located over large parts of the Sichuan Basin and southern China. After the MASH procedure, LSTs at more than 80% of the breakpoints are adjusted within +/– 0.5°C, and of the remaining breakpoints, only 10% are adjusted over 1.5°C.Compared to the raw LST dataset over the whole domain, the homogenization significantly reduces the mean LST magnitude and its interannual variability as well as its linear trend at most stations. Finally, we perform preliminary analysis upon the homogenized LST and find that the annual mean LST averaged across China shows a significant warming trend [0.22°C(10 yr)–1]. The homogenized LST dataset can be further adapted for a variety of applications(e.g.,model evaluation and extreme event characterization).     

砾石单元法与SPH耦合模型在数值波浪水槽中的应用研究

为研究以流体粒子描述波浪运动,以固体单元描述砾石运动的两相介质大变形运动,在港口、海岸工程科学研究中具有重要意义。本文提出砾石单元法(GEM),介绍了光滑粒子动力学方法 (SPH)和GEM的基本原理,阐述了GEM与离散单元法(DEM)的异同之处,说明了采用SPH方法与GEM构建波浪砾石耦合运动数学模型的方法和过程。应用SPH方法建立数值波浪水槽,用GEM模拟波浪作用下堆积砾石的滚落、坍塌变形,构建了SPH方法与GEM耦合数学模型。模拟了水槽造波和波浪生成过程和波浪作用下砾石的滚落、坍塌变形,并与物理模型试验成果进行了比较,结果基本吻合。本文提出的GEM法具有模拟单相堆积砾石运动和堆积砾石与流体粒子耦合多相介质运动的功能,是对DEM法的补充和改善。本文提出的堆积力学球概念和拟序排列求解方法是砾石单元法的重要组成部分。     

天然气水合物准三维地震勘探电缆动态定位精度研究

在我国某海域对天然气水合物研究过程中,使用了单源单缆准三维地震勘探方法,获得了较好的天然气水合物矿体三维成像效果.影响天然气水合物矿体三维成像的因素很多,其中,电缆动态定位精度是最直接的影响因素之一.在大量试验数据的基础上,研究了罗盘对电缆动态定位精度的影响,研究结果与海试资料及国内外资料非常吻合,这对天然气水合物准三维调查具有一定的指导意义.根据该研究结果,在保证一定定位误差的前提下,最终确定了电缆的排列长度为2 400 m(192道),获得了较高的动态定位精度.2007年在该海域实施了钻探,国内首次发现了水合物样品.钻探结果与地震资料的吻合证实了准三维地震方法定位精度已达到较高的程度.     

四川那朗地区多金属矿化地质及激电特征

四川那朗地区地处三江成矿带,区内出露三叠系灰岩、板岩及火山岩,有闪长岩岩株侵入其中,地表见铁帽。岩体蚀变分带明显。通过激发极化法工作,由视极化率处理后异常显示,原始数据圈出了激电异常,推测为铁帽下部之矿（化）致异常。     

MT法中利用阻抗相位资料对畸变视电阻率曲线的校正

从理论上论证了在一定条件下大地电磁响应中的相位资料将不受随机电磁噪声的影响，介绍了由相位资料递推计算视电阻率的方法，通过与远参考资料的比较，证明利用阻抗相位资料可分段恢复校正畸变的实测视电阻率数据。