跨断层测量不等间隔计算的数据匹配

跨断层测量的数据处理中,常利用不等间隔数据进行计算,由此产生一系列问题,如时间计算、同步性、主从关系、可比性等。对此,从合理、最佳的要求出发,以约定的方式进行设计,考察它们在多种算法中的适应能力,有利于跨断层测量数据处理的完善和发展。
     

中国主要地震活动区的地震间隙分布

结合地震间隙和强度变化分析了本世纪全国及国内主要地震活动区中强以 上地震活动特征,间隙大多在５．５ａ内,一半以上在２．５ａ内,最大间隙近１８ａ.５０年代 以后全国７．５级以上和７．０级以上、青藏块体７．０级以上地震活动及近２０ａ来台湾 ７．０级以上、华北和四川６．０级以上地震活动明显减弱,２０－３０年代青藏块体北部大 震的活动影响一直持续到７０年代,５．０－６．５级地震活动自８０年代明显增强,云南 ７０年代后形成的地震活动高潮实际上从６０年代就开始增强,华北和台湾地区表现 了强震前活动增强而甘宁青地区表现了强震后活动衰减的典型过程,制约我国地震 活动的大三角应力场、东部应力场和全球应力场具有长期稳定的２０ａ周期性,后面的 应力场依次滞后于前一个应力场约１／４个周期,前两者起主导作用,青藏块体东北缘 的地震活动除受东部应力场的影响外,还与青藏块体地壳物质东流的重要作用有关, 今后几年要特别注意四川和甘宁青６．０级以上、甘肃地区５．０级以上及新疆７．０级 以上地震。     

中国大陆若干地震构造带的地震准周期丛集复发行为

以青藏高原东南缘和东北缘若干地震构造带的历史地震活动资料为基本数据，通过地震复发间隔的计算，分类和统计检验等，研究了大陆板内地震的复发行为。认为：大陆板内地震既不是简单地准周期重复发生，也不是简单地丛集复发，而可能是一种准周期的丛集复发行为，即地震丛是准周期重复发生的，而在某一地震丛内，地震又是丛集复发的。存在两类地震复发间隔，即地震丛复发间隔和地震丛内的地震复发间隔，它们分别满足对数正态分布和指数分布。在进行大陆板内活动断裂地震危险性定量计算和评估时，不能简单地套用N．B．实进模型中给出的地震复发间隔概率密度函数或累积分布函数，而应该根据当前地震的活动水平，判断当前是属于丛内的活跃期还是丛间的平静期，据此分别选用地震丛内地震复发间隔分布函数或者地震丛复发问题隔分布函数，这样将大大提高活动断裂地震危险性计算和定量评估的水平。最后，简要探讨了大陆板内地震准周期丛集复发行为的可能物理机制。     

中国油页岩矿勘查控制程度探讨

为提高我国油页岩矿勘查工作质量，根据我国47个典型油页岩矿勘查评价成果和油页岩矿成矿地质条件及矿层赋存规律，通过综合分析研究，采用探采对比及抽稀试验进行验证，提出了我国油页岩矿勘查评价采用构造复杂程度和矿层稳定程度两种地质因素确定勘查类型。构造复杂程度划分为简单、中等、复杂3类；矿层稳定程度划分为稳定、较稳定和不稳定3型，即"三类三型"。类型为简单、稳定时，参考基本勘查工程间距采用1 000~2 000 m；类型为中等、较稳定时，参考基本勘查工程间距采用500~1 000 m；类型为复杂、不稳定时，参考基本勘查工程间距采用250~500 m。另外，在油页岩矿实际勘查工作中应在构造复杂程度和矿层稳定程度中选择勘查难度大者确定基本勘查工程间距。     

合肥地区地闪特征

根据观测资料 ,分析了利用闪电辐射场信号大容量采集系统观测到的合肥地区地闪回击特征。结果表明 ,每次地闪回击数频率分布并不表现为简单的指数衰减特征 ,回击数在 5次以下的各回击数出现频率几乎相当 ,单次回击地闪的比重只有约 1 5 %。平均地闪回击数为 4 .2次 ,观测到的最大回击数为 1 6次。地闪回击归一化电场强度近似服从对数正态分布。 1 69例首次回击平均电场强度为 9.3V·m- 1 (归一化到 1 0 0km ,下同 ) ,485例继后回击的平均电场强度只有 4 .5V·m- 1 。 480例继后回击与首次回击场强之比平均为 0 .6 ,有 1 8%地闪过程至少有一次比首次回击强的继后回击。相邻两次回击间隔时间呈现对数正态分布特征。观测到的最短回击间隔为 1 .6ms ,约 30 %的回击间隔 >1 0 0ms,在40～ 1 0 0ms之间的回击间隔比重约为 50 %。回击间隔时间与间隔前后回击相对强弱之间存在系统性的变化趋势 ,当两次回击间隔在 40ms以下时总是以‘前强后弱’的回击组合占主导地位 ,相反 ,当回击间隔时间增加到 >1 0 0ms时 ,约 55 %的回击间隔表现为‘前弱后强’的回击组合。     

岩石点荷载强度与单轴抗压强度线性关系试验

针对目前岩石点荷载试验大部分采用规则试件进行,试件加工制作及试验的过程繁琐、成本高的问题,通过自制点荷载试验仪以及RMT-150B岩石力学伺服试验机,对煤矿顶底板常见岩性进行不规则岩石试件点荷载试验和规则岩石试件单轴抗压试验。试验结果表明：不规则岩石点荷载强度基本上满足正态分布规律,同时,点荷载破坏载荷与破坏面积之间呈线性关系,不同载荷破坏面积对点荷载试验中的尺寸、形状效应基本上没有太大的影响。通过分析点荷载强度与单轴抗压强度两者间的关系,得出通过点荷载强度确定单轴抗压强度的经验公式。     

SAR立体影像匹配的视差图融合方法

提出了一种基于视差图融合的匹配方法。首先,基于归一化互相关系数(normalized cross correlation,NCC),利用多个不同尺寸的匹配窗口分别进行匹配,获取相应的视差图;然后,提出了一种左右一致性(left right consistency,LRC)和信噪比(signal to noise ratio,SNR)相结合的置信测度,用来评价视差图中每个视差的置信水平;在此基础上,提出了一种视差图融合策略,该策略对上述多个匹配窗口获取的视差图进行加权融合,融合时既考虑了视差本身的置信水平,也兼顾了其邻域视差的影响。采用TanDEM-X的聚束立体影像进行试验,结果表明,本文方法能有效减少DEM粗差点,DEM高程精度由11.28 m提高到8.41 m。     

Simulation of summer storms of differing recurrence intervals in a semiarid environment using a kinematic routing scheme

A kinematic flood routing procedure has been devised for a small dendritic headwater gully network on the Western slope of Colorado. the program is spatially-distributed, incorporating lateral inflows from 103 field sites on the network for which channel geometry variables are known. This model, in which a lateral inflow algorithm for the sideslopes between each channel site is convoluted into a Freeze-type (1978) numerical scheme, is fully developed in this paper. Although the field basis of the lateral inflow algorithm has been tested elsewhere (Faulkner, 1990), sensitivity tests were needed for the roughness and hillslope velocity estimates used in the routing procedure. After these successful tests, a suitably precalibrated run of the model was compared with a field-monitored runoff event on the watershed, and results again were encouraging. However, peak attentuation downstream was more pronounced in reality than on the simulation, so the model was also modified by inclusion of allowances for transmission loss. the tendency that the model had displayed for peak size attenuation downstream was considerably enhanced. Using the model, the geomorphic role of the flashfloods which affect the watershed in the summer months is briefly considered by applying the model to existing records of local summer storm rainfall events as a basis for event simulation. These simulations show that downstream attenuation of the flood wave on concave networks in steep semiarid terrain was likely to be a common occurrence, possibly resulting in down-net deposition and differences in geomorphic behaviour between upstream and downstream sites. the discussion is finally broadened to consider the relative importance of ‘common’ as compared to ‘freak’ watershed events in maintaining these differences.     

On comparative probabilities for normal confidence intervals by pearson's Types III and VII, and the Edgeworth series models for biotite data

Biotite crystals were counted in standard thin sections which originated from the diamond drill core of the mafic norite formation at Strathcona mine, Sudbury Nickel Irruptive. Pearson's method of moments is suitable to fit Types III and VII to the biotite data and its log ₁₀ transformation values, as the number of samples (thin sections)is large (351).Based on the two models and the Edgeworth series (utilizing the log ₁₀ data)probability values p,that biotite occurrences lie in the interval mean ± Z standard deviations is derived. Results are compared with the usual normal probability values p_Z corresponding to Zand it is shown that the Edgeworth series generated the largest pvalues for intervals when p_Z values are large; for intermediate or lower p_Z s. Types VII and III models produced larger ps, relative to the Normal and the Edgeworth series.     

Variability of unconfined compressive strength in relation to number of test samples

Unconfined compressive strength is one of the most commonly used properties in rock engineering. Estimation or selection of an appropriate value of unconfined compressive strength for a given rock can be difficult as it can vary greatly within the same rock unit. Considering this large variability, unconfined compressive strength obtained by testing just a few samples is questionable. The purpose of this study was to investigate the variability of unconfined compressive strength for a given rock and, based on this information, determine the minimum number of samples required for obtaining a reliable value. Unconfined compressive strength values for approximately 50 NX-size (2.125 in./5.4 cm) core samples were determined for five different rock types. Statistical analyses were performed on subsets of cores to determine the minimum number of samples required to render a reliable estimate of the average strength of the entire set of cores. The results indicate that the minimum number of samples needed for strength determination depends on the statistical method used, the chosen confidence interval, and the acceptable deviation from the mean. For a 95% confidence interval and a 20% acceptable strength deviation from the mean, either 9 or 10 samples are needed to test for strength, depending on the statistical analysis used.