重磁３Ｄ反演在新疆伊吾县宝山铁矿找矿增储中的应用

[摘 要] 新疆伊吾县宝山铁矿是一个小型富磁铁矿矿床,经过多年开采浅表矿体开采殆尽,成为危机矿山,找矿增储是延长矿山服务年限的当务之急。本研究在宝山铁矿床开展了超高密度的高精度磁法、重力面积测量,采用重磁三维反演技术,获得了矿区地下密度体和磁性体的三维分布信息。结合地质资料,对反演结果分析解释,认为宝山铁矿深部存在隐伏矿体,选择异常套合较好地段进行钻探验证,发现了隐伏的磁铁矿矿体,缓解了矿山的危机。认为宝山铁矿深部还有较大的找矿空间,同时也证明重磁三维反演在隐伏矿找矿中具有十分广阔的前景。     

三维边坡最不利滑裂面的遗传算法搜索

将遗传算法引入到三维边坡稳定分析中。由于三维边坡滑裂面的复杂性,需对滑裂面作适当简化。认为滑裂面为椭球面,用7个控制参数来模拟生成滑裂面,再运用遗传算法来搜索滑坡的最不利的滑裂面。对于存在确定滑裂面的滑坡,7以将此滑裂面作为整体滑裂面,计算其整体稳定安全系数,然后在整体稳定的基础上,运用遗传算法搜索滑坡内部的最不利滑裂面,得出滑坡最小的稳定安全系数。     

Limit equilibrium method based on an approximate lower bound method with a variable factor of safety that can consider residual strength

In this paper, the factor of safety for a prescribed slip surface will be determined from an equivalent lower bound method (extremum principle), which can satisfy all equilibrium conditions without an interslice force function. This approach will give an overall factor of safety close to that from the classical methods for normal problems, while the thrust line, the local factor of safety for individual slice/block and the progressive yielding phenomenon can be estimated, which will be useful for some special cases. The force and moment equilibrium of every slice will be satisfied, while the location of the thrust line will always be acceptable in the present formulation. To solve the difficult optimisation problem, an innovative coupled particle swarm/harmony search algorithm is proposed in this paper, and a practical engineering problem for which the factor of safety is close to 1.0 is used to illustrate the consideration of the residual strength in the limit equilibrium slope stability analysis.     

样条函数模拟土坡滑动面的效率分析

土坡稳定分析中,二维滑动面通常由一系列点顺序连接产生,并且将点的坐标当作优化变量来搜索临界滑动面,当点的个数较多时会导致优化变量较多;只需给定少量的控制节点,即可利用三次样条函数得到光滑的曲线作为任意滑动面,该法对于含软弱夹层土坡,无需事先指定直线段。利用不平衡推力法计算给定滑动面的安全系数,采取和声搜索算法确定最小安全系数相应的临界滑动面。对3个土坡算例进行了比较分析,比较了常规策略与样条函数方法在模拟土坡滑动面时的效率。     

东天山白石泉一带铜镍矿成矿模式及找矿模型

新疆哈密市白石泉一带发现的白石泉、天宇和天香等铜镍矿床(点),均位于中天山地块北缘,沙泉子大断裂南侧.本区铜镍矿数量少、规模小,但成矿条件优越,具寻找新矿床及大型矿床潜力.本文通过对3个典型矿床成矿背景、地质特征进行总结,寻找各矿床在成因上的内在联系,建立铜镍矿成矿模式和找矿模型,为下一步找矿指明方向.     

Progress in study of Chinese Antarctic Meteorites

This paper reviews and summarizes the Chinese Antarctica meteorite search, classification and research. During the past four antarctic explorations, a total of 9834 meteorites were collected in the Grove Mountains region. Among them, 2431 meteorites were classified by the end of 2008. So far, 684 meteorites have been officially published in the Meteoritical Bulletin, Meteoritical Society, including 2 martian meteorites, 2 eucrites, 6 ureilites, 5 mesosiderites, 1 pallasite, 1 iron and 10 carbonaceous chondrites. Comprehensive studies were carried out on a number of these rare type meteorites. In addition, we propose to continue the meteorite searching project in Grove Mountains and other regions in Antarctica. We also suggest several key topics of the future researches on the Chinese Antarctic meteorites.     

图像检索技术研究进展

近年来,互联网上视觉数据呈现出爆炸式的增长,越来越多的研究工作围绕图像搜索或图像检索技术而展开.早期的搜索技术仅采用文本信息,忽视了视觉内容作为排序的线索,导致搜索文本和视觉内容不一致.基于内容的图像检索（CBIR）技术充分利用视觉内容识别相关图像,在近几年来获得了广泛关注.在图像检索中,最根本的问题是意图鸿沟和语义鸿沟,围绕该问题,近年涌现出大量的基于内容的图像检索的技术.本文主要对2003-2016年间提出的相关图像检索方法进行总结、分类和评估,并对未来的潜在研究方向进行讨论.     

论四川盆地海相三叠系含钾性及找钾方向

据现有资料，阐述了四川盆地三叠系含钾性及找钾的现实意义。同时论述了在四川盆地找寻大型固相可溶性钾矿之难度，提出了开辟富钾卤水或含钾卤水──液态钾矿资源的找矿工作是突破四川找钾工作的一个重要和有效途径。     

东天山成矿规律与找矿方向的初步研究

根据对东天山1500多处矿产地时空分布规律的初步研究,认为东天山具有矿产资源丰富、矿种多,铁铜镍煤盐等优势矿产比较明显、矿床类型较全、成矿历史悠久、空间分布相对集中且呈“南铁北铜东镍中间金”的特点。鉴于东天山地区基础地质工作程度偏低。科学研究深度不够,根据其地质演化规律和区域对比,认为东天山地区今后的找矿工作既要重视深入研究典型矿床,在查明矿床成因的基础上建立成因模式、找矿模型和综合评价模型,也要不同矿种之间、先后地质时代之间、相邻成矿区带之间相互借鉴,开拓思路,以期取得新进展。建议国家和相关产业部门以铁、铜为导向,集中目标开展找矿会战并带动其他矿种实现找矿新突破。     

The May 23 and 24, 1994 Taiwan earthquakes: comparison of source process between the two events

Inversion for the seismic fault rupture history is an important way to study the nature of the earthquake source. In this paper, we have selected two Taiwan earthquakes that occurred closely in time and located in the same region, inversed the distribution of the slip amplitudes, rakes, risetimes and the rupture times on the fault planes by using GDSN broad-band and long-period records and the adaptive hybrid global search algorithm, and compared the two events. The slip rate of every subfault calculated provides information about the distribution of tectonic stress and fault strength. To the former event (MS=6.0), the maximum slip amplitude 2.4 m and the minimum risetime 1.2 s are both located at the hypocentre. The latter earthquake (MS=6.6) consisted of two subevents and the second source has 4 s delay. The maximum slip amplitude 0.9 m located near hypocentre is corresponding to the minimum risetime 1.4 s, and the corresponding maximum slip rate 0.7 m.s-1 is similar to the peak value of other large slip rate areas. We consider that the latter event has more complicated temporal-spatial distribution than the former.