超压真空密实技术在尾矿库治理中的应用研究

超压真空密实技术是近几年发展起来的软土处理技术,采用独特防淤堵排水板、结合增压技术,用于矿山尾矿库的加固治理,提高尾矿库安全,避免事故的发生。     

Jurassic Tectonics of North China: A Synthetic View

This paper gives a synthetic view on the Jurassic tectonics of North China, with an attempt to propose a framework for the stepwise tectonic evolution history. Jurassic sedimentation, deformation and magmatism in North China have been divided into three stages. The earliest Jurassic is marked by a period of magmatism quiescence （in 205-190 Ma） and regional uplift, which are considered to be the continuation of the “Indosinian movement” characterized by continent-continent collision between the North and South China blocks. The Early to Middle Jurassic （in 190-170 Ma） was predominated by weak lithospheric extension expressed by mantle-derived plutonism and volcanism along the Yanshan belt and alongside the Tan-Lu fault zone, normal faulting and graben formation along the Yinshan- Yanshan tectonic belt, depression and resuming of coal-bearing sedimentation in vast regions of the North China block （NCB）. The Middle to Late Jurassic stage started at 165y.5 Ma and ended up before 136 Ma; it was dominated by intensive intraplate deformation resulting from multi-directional compressions. Two major deformation events have been identified. One is marked by stratigraphic unconformity beneath the thick Upper Jurassic molasic series in the foreland zones of the western Ordos thrust-fold belt and along the Yinshan-Yanshan belt; it was predated 160 Ma. The other one is indicated by stratigraphic unconformity at the base of the Lower Cretaceous and predated 135 Ma. During this last stage, two latitudinal tectonic belts, the Yinshan-Yanshan belt in the north and the Qinling-Dabie belt in the south, and the western margin of the Ordos basin were all activated by thrusting; the NCB itself was deformed by the NE to NNE-trending structural system involving thrusting, associated folding and sinistral strike-slip faulting, which were spatially partitioned. Foliated S-type granitic plutons aged 160-150 Ma were massively emplaced in the Jiao-Liao massif east of the Tan-Lu fault zone and indicate important crustal thicken     

西藏冈底斯带侏罗纪岩浆作用的时空分布 及构造环境

在新近完成的1：25万区域地质调查资料和相关研究成果的基础上,初步研究了西藏冈底斯带侏罗纪岩浆作用的分布特点及其年代学,并利用已有的地球化学数据重点分析了早期关注程度较低的侏罗纪花岗岩类岩浆作用的性质。目前在冈底斯弧背断隆带未发现侏罗纪火山岩;在冈底斯东部地区,早侏罗世岩浆活动几乎同时发生于南冈底斯（叶巴组火山岩和鸟郁、尼木花岗岩类）、冈底斯弧背断隆带（宁中、金达、布久花岗岩类）和北冈底斯（聂荣花岗岩类）,中晚侏罗世接奴群和拉贡塘组火山岩断续分布于北冈底斯,晚侏罗世岩浆活动零星分布于沙莫勒一麦拉一洛巴堆～米拉山断裂以北。将冈底斯侏罗纪岩浆活动置于时空框架内分析发现,南冈底斯和北冈底斯在侏罗纪时主要受俯冲作用的影响．而冈底斯弧背断隆带和中冈底斯自早侏罗世以来除了受到俯冲作用的影响外,还受到自东向西逐步扩展的碰撞作用的影响。结合古地磁重建资料和其他新发现．认为冈底斯带侏罗纪这种岩浆活动的特点可用班公湖一怒江洋壳向南、新特提斯洋壳向北的双向剪刀式（剪刀口向西张开）俯冲模式来解释。     

Isotopes and Geochronology of the Meixian-type Pb-Zn-(Ag)Deposits,Central Fujian Rift,South China:Implications for Geological Events

Central Fujian Rift is another new and important volcanogenic massive sulfide Pb-Zn polymetallic metallogenetic belt. In order to find out the material genesis and mineralization period of Meixian-type Pb-Zn-Ag deposits, S and Pb isotope analysis and isotope geochronology of ores and wall rocks for five major deposits are discussed. It is concluded that the composition of sulfur isotope from sulfide ore vary slightly in different deposits and the mean value is close to zero with the 834S ranging from -3.5‰ to ＋5.6‰ averaging at ＋2.0‰, which indicates that the sulfur might originate from magma or possibly erupted directly from volcano or was leached from ore-hosted volcanic rock. The lead from ores in most deposits displays radioactive genesis character （206pb/204pb〉18.140, 207Pb/204pb〉15.584, 208pb/204pb〉38.569） and lead isotope values of ores are higher than those of wall rocks, which indicates that the lead was likely leached from the ore-hosted volcanic rocks. Based on isotope data, two significant Pb-Zn metallogenesis are delineated, which are Mid- and Late-Proterozoic sedimentary exhalative metailogenesis （The single zircon U-Pb, Sm-Nd isochronal and Ar-Ar dating ages of ore- hosted wall rocks are calculated to be among 933-1788 Ma.） and Yanshanian magmatic hydrothermal superimposed and alternated metallogenesis （intrusive SHRIMP zircon U-Pb and Rb-Sr isochronal ages between 127-154 Ma）.     

祁连山不同植被类型对积雪消融的影响

为研究祁连山植被对积雪消融的影响, 利用人工调查积雪深度逐日变化量和积雪盖度变化, 并结合空气雪面感热通量(SH)观测, 对祁连山水源林生态站排露沟流域海拔2 600～2 700 m青海云杉林、灌丛林、林缘、阳坡草地在2003-2007年的积雪消融进行了研究, 每年的观测从10月降雪开始到翌年5月积雪消融完结束, 共获取数据134 400个. 结果表明: 当SH<0时, 积雪消融停止;当SH>0时, 积雪消融开始;植被可以减缓积雪消融速率, 有植被的地方消融速率减慢, 反之则加快;不同植被消融速率大小顺序为草地>林缘>灌木林>乔木林;同一植被、不同坡向消融速率不同, 半阳坡云杉林＞半阴坡云杉林＞阴坡云杉林. 积雪含水率随气温升高而增大, 1月融化积雪占整个积雪的5%, 2月增大到28%, 大量积雪在3月消融, 占55%. 从坡位看, 下坡消融速率最大;在一个垂直带上, 低海拔消融速率大于高海拔. 温度是影响积雪消融的主要因子, 积雪消融速率随温度升高而增大, 反之则减小.     

柴达木盆地东北缘中新统遗迹化石组合及其沉积环境

研究遗迹化石对于恢复古生物活动方式、习性和古环境具有重要意义。在柴达木盆地东北缘双湖地区中新统发现了遗迹化石。经鉴定,研究区的遗迹化石主要包括2大类4属4种:居住迹Palaeopycus heberti（赫伯特古藻迹）,Skolithos verticalis（垂直石针迹）;进食迹Scoyenia gracilis（纤细斯柯茵迹）和Taenidium satanassi（箱形条带迹）。根据研究区的遗迹化石分布及沉积环境分析,该地可划分出一个遗迹组合:Scoyenia-Taenidium-Skolithos遗迹组合, 代表了潮湿气候条件下的浅湖环境。当前化石的发现填补了柴达木盆地东北缘双湖地区中新世遗迹化石研究的空白。     

甘肃省文县阳山金矿安坝里南矿区矿石特征及金矿物赋存状态研究

甘肃阳山金矿安坝里南矿区是阳山金矿勘查程度最高的区段。矿区赋矿地层为泥盆系中统三河口群第三岩性段,控矿构造为安昌河—观音坝断裂。主要矿石类型为蚀变千枚岩型及蚀变斜长花岗斑岩型,其中金属矿物占3.51%,以黄铁矿、毒砂、辉锑矿为主,属贫硫型矿石。矿石中有益组分主要为金,其它有益组分不具备综合利用价值。主要载金矿物为黄铁矿,其次为毒砂。金矿物主要以包裹金、粒间金两种状态产出,以包裹金为主,该赋存状态有利于金矿物的浮选回收。     

红层与煤系复合结构覆岩采动破坏分析及其应用

许多矿区煤层采动影响范围内的覆岩层由红层和煤层共同构成。本文研究了山东省太平煤矿东区二叠系 3号煤层覆岩破坏和防水煤柱留设的问题 ,在对上覆第四系水文地质条件分析的基础上 ,对红层和煤系复合结构覆岩的工程地质特征和破坏状况进行了分析 ,确定了合理的防水煤岩柱高度 ,并经过开采验证 ,避免了水害发生.     

电吸附找矿方法

电吸附找矿方法是找隐伏矿的新方法.它是指通过物理化学手段来发现后生地球化学异常的找矿方法.它是建立在异常元素地球化学理论和野外地电提取法的理论基础之上.利用电吸附找矿方法在一些已知矿床进行找矿效果试验,获得了很好的效果,说明了该方法找矿的有效性.     

海南抱伦金矿的成矿时代研究及其意义

抱伦金矿床是海南省新近发现的大型金矿床之一,属于发育于下志留统陀烈组浅变质岩系中受断裂裂隙构造控制的岩浆热液型金矿床。研究表明：与成矿有关的尖峰岭复式岩体中心相的侵位时代为236～232Ma,经历了长期多次多阶段的侵位,抱伦金矿床的成矿年龄确定为大约220Ma(印支期),二者的年龄差大约为16～12Ma。岩体的脉动式活动为形成高品位金矿石提供了物质和动力来源。