贵州省烂泥沟金矿外围成矿远景浅析

烂泥沟金矿是贵州省贞丰县的大型金矿资源,随着金矿的开发,需要在其外围找到代替的矿产,以解决资源问题。文章通过结构区域地质特征和矿体特征,并通过一定的地球物理和地球化学方法,对烂泥沟金矿外围成矿条件进行分析,得出相应矿体异常的特征区。     

地球化学测量方法对金矿勘察的作用

地球化学测量是目前金矿勘察中采用的一种具有较大穿透力的矿床勘察措施和方法,是目前工作中通过不损坏地表景观条件的基础上进行土壤金矿矿床勘察。这种勘察措施和方法在勘察工作中较为常见,同时对于寻找外来运积物覆盖区的隐伏金矿具有良好的效果。本文就地球化学测量方法进行分析,并对于金矿勘察的作用进行分析与阐述。     

山阳县桐树沟金矿地质化探综合特征及控矿规律

桐树沟金矿赋存于中泥盆统牛耳川组及大枫沟组构造破碎带中,矿体受区域大断裂及其次级构造控制,呈脉状产出,围岩蚀变主要为硅化、铁方解石化、黄铁矿化、褐铁矿化。本文根据对矿体赋矿层位及岩石、构造条件、化探异常分布规律、矿化蚀变类型等因素综合分析,认为桐树沟金矿属构造蚀变岩型和石英脉型金矿。造破碎带内石英脉是主要赋矿岩石,区域构造及其次级构造是控矿主导因素,控制了矿体的形态和规模,化探异常的分布显示了矿化在地表的范围,矿化蚀变特征提供了找矿标志。     

谈盐晕找矿的地球化学依据

大量的实验研究结果表明,盐晕找矿技术方法虽然分析成本高于常规化探或者说高于其他化探方法,但盐暈找矿技术应用于化探异常评价中筛选矿致异常与非矿致异常,以及排除干扰异常,有着其独特的指示效果,其作用是任何一种化探方法都无法取代的。盐晕的形成过程受一系列表生地球化学条件的控制,它主要经历元素的转入溶液、在溶液中的迁移及从溶液中析出三个阶段。     

新疆新源县脱勒一带化探金异常及其成矿预测

文章探讨了新源县脱勒一带化探金异常的特征、构造、地层及航磁、重力等情况,总结了该区的成矿规律,并对该区的金矿位置进行了初步圈定。     

新疆新源县脱勒一带化探金异常及其成矿预测

文章探讨了新源县脱勒一带化探金异常的特征、构造、地层及航磁、重力等情况,总结了该区的成矿规律,并对该区的金矿位置进行了初步圈定。     

厚层坚硬顶板破断规律和矿压显现特征

文章基于厚层坚硬顶板的典型地质特征,通过理论计算和数值模拟等方法,分析了厚层坚硬顶板的破断规律和矿压显现特征;相关研究成果对类似地质条件下工作面坚硬顶板管理,有着较为重要的实际意义和借鉴价值。     

复杂条件下交叉点的台棚支护技术探讨

高应力、大采深台棚支护一直是制约林西矿改变生产模式、推行综采施工的一个重要环节,经过不断摸索探究,找到了一条适合林西复杂条件下交叉点的施工方法,为衰老矿井在复杂条件下交叉点的支护方面提供了借鉴。     

鳌山污水处理厂厂区地基选择与评价

为了满足鳌山污水处理厂厂区建设需要,选择经济、合理、安全的基础持力层,在通过工程地质勘察、现场实验、室内实验等多种手段获得了各项工程地质参数的基础上,综合多种计算方法,分析评价存在厚层软弱土层地基条件下选用浅层地基土作为持力层的可能性。论证了有效利用高压缩、低承载力土层上部可以作为持力层使用的"硬壳"土层,可以避免使用深基础及大规模的地基处理,并同时满足工程建设的安全性需要,从而减小工程投入,加快施工进度。     

威宁县苗寨铅锌矿地质特征及找矿远景

笔者通过对威宁县苗寨铅锌矿地找矿工作经验的描述,以及对丫都、天桥、横坡等矿点进行分及对比分析,熟悉了该区铅锌矿成控矿条件和控矿因素。现结合威宁云贵桥苗寨铅锌矿产出地质特征、物探及化探的有关资料等,笔者认为威宁苗寨铅锌矿区F1断层及云贵背斜为区内主要控矿构造,在F1断层旁侧及大苗寨、银槽子两个异常区有找矿的潜力。     

土壤地球化学测量在陇宝地区金矿勘查中的应用及找矿效果

陇宝地区开展土壤地球化学测量的背景是该区开展了1:10万水系沉积物铀、金测量2143km2;通过对所发现的远景区开展土壤地球化学测量,掌握了区域地球化学特征,区内土壤金异常产出特点,总结了该方法的应用技术、应用流程。从找矿实测证明了土壤地球化学测量在该区的找矿效果。     

Portfolio management using a factor-analytic stock selection strategy

This study takes an integrated look at six widely documented price-related CAPM anomaly variables. Using maximum likelihood factor analysis, we extract factors common to these variables. We find that portfolios formed according to the first extracted factor alone exhibit abnormal performance. Further, the performance of firms ranked on the basis of extracted factor scores for this factor is superior to that of firms selected on the basis of any one of the six variables. Our results have implications for (1) isolating missing factors in the CAPM specification and (2) designing dynamic portfolio strategies aimed at jointly exploiting more than one anomaly.     

海南儋州走兵岭多金属矿地球化学特征及成矿预测

海南省儋州市走兵岭多金属矿,是受北东和北北西向两组断裂控制的石英脉型金矿床。通过区域地质背景及矿区Au元素地球化学异常特征的分析研究,为该矿床或同类矿床的找矿提供一定线索。     

Price gap anomaly in the US stock market: The whole story

This paper analyses the price gap anomaly in the US stock market (comprised of the DJI, S&P 500 and NASDAQ) covering the period 1928 to 2018. This paper aims to investigate whether or not price gaps create market inefficiencies. Price gaps occur when the current day’s opening price is different from the previous day’s closing price due orders placed before the opening of the market. Several hypotheses are tested using various statistical tests (Student’s t-test, ANOVA, Mann-Whitney test), regression analysis, and special methods, that is, the modified cumulative returns and the trading simulation approaches. We find strong evidence in favour of abnormal price movements after price gaps. We observe that during a gap day prices tend to change in the direction of the gap. A trading strategy based on this anomaly was efficient in that its results were not random, indicating that this market was not efficient. The momentum effect was found to be temporary and no evidence of seasonality in price gaps was found. Lastly, our results were also contrary to the myth that price gaps tend to get filled.     

GIS设备局部放电分析及对策研究

现阶段,对GIS绝缘的在线监测和诊断最直接有效的方法就是进行局部放电的监测,通过监测GIS设备在运行时的绝缘状态,及时发现可能出现的异常和故障的预兆,采取正确的处理措施,保证设备运行安全和稳定。本文主要介绍GIS局部放电在线监测的方法和优缺点以及举例110kV GIS设备的局部放电异常分析和处理对策。     

What does Variation in Survey Design Reveal about the Nature of Measurement Errors in Household Consumption?

We randomly assigned eight different consumption surveys to obtain evidence on the nature of measurement errors in estimates of household consumption. Regressions using data from more error‐prone designs are compared with results from a ‘gold standard’ survey. Measurement errors appear to have a mean‐reverting negative correlation with true consumption, especially for food and especially for rural households.     

石楼隧道下穿积水沟谷浅埋段施工技术

石楼隧道下穿黄土沟谷浅埋段,沟谷内常年积水、流水,淤积层较厚,隧道洞身为松软状粉质黏土,施工中极易掉块、坍塌,通过对下穿施工技术进行总结,对类似工程施工中针对不同水文、地质和施工等因素的影响下如何确保施工安全质量提供一定的参考。     

Technology transactions,announcement effect,and reversal: Dissecting an anomaly

We examine the short term stock price performance of firms that acquire or sell technology rights. We find significant positive announcement-period abnormal returns to the acquirers and sellers. However, the price increases reverse during the subsequent twenty trading days. These quick fortune reversals cannot be attributed to methodology; they prevail in the late 1970s through the 2000s, in bear and bull stock markets, and in both high and low technology industries. Upon splitting the sample into two subsamples comprised each of stocks with either pre-announcement price run-up or decline; we find that the abnormal return reversal is confined to the latter subsample. Stocks that witness price run-up prior to the announcement do not reverse to original prices but lose the momentum right after the announcement-period. We believe this is caused by the combination effect of the momentum prior to-and the impact of the announcement.