新疆红十井金矿床特征及成因   总被引：2，自引：0，他引：2  

肖惠良  周济元  王鹤年  崔炳芳  陈世忠 《矿床地质》2003,22(1):32-40

文章通过K_Ar同位素年龄 ,氢、氧、硫、铅等同位素测试和流体包裹研究 ,结合红十井金矿床的地质、矿区岩石化学、微量元素及稀土元素地球化学特征 ,探讨了红十井金矿床含金建造与金矿关系及矿床成因。研究表明红十井金矿床为晚古生代裂谷带火山岩区受韧性剪切带控制的中_低温热液矿床 ,矿体赋存于中石炭统玄武 (玢 )岩及凝灰质砂岩组成的含金建造内 ,成矿物质主要来源于含金建造 ,矿化以蚀变岩型和石英脉型为主。成矿年龄为2 0 9～ 2 6 7Ma。成矿流体为岩浆水、玄武 (玢 )岩和凝灰质砂岩的变质水、建造水和大气降水的混合溶液 ,δD为 - 114.6‰～ - 6 8.8‰ ,δ18OH2 O变化为 - 2 .47‰～ 5 .91‰。成矿温度为 115～ 381℃ ,成矿压力为 471.8× 10 5～ 6 75 .9× 10 5Pa ;流体盐度w(NaCleq)为 2 .18%～ 16 .77% ,平均 7.79% ,流体属中_低盐度、H2 O_CO2 体系。  相似文献   

新疆乌恰县乌拉根新生代热卤水喷流沉积铅锌矿成因研究   总被引：18，自引：3，他引：18  

谢世业  莫江平  杨建功  杨金明 《矿产与地质》2003,17(1):11-16

乌拉根铅锌矿床是新生代卤水喷流沉积矿床，矿化分布于下第三系古新统乌拉根组第一、二岩性段，矿石结构构造兼有同生沉积及叠加改造特征，围岩蚀变为黄铁矿化、天青石化、石膏化及白云石化。通过研究表明：成矿物质铅锌来自地壳深部或上地幔，硫主要来自海水硫酸盐的还原；成矿温度为64-193℃；成矿流体盐度7.22%-20.29%WtNaCl；成矿年龄45.4-54.0M。指出成矿作用经历了三个时期：a、热卤水喷流沉积成矿斯；b、热卤水喷溢叠加成矿期；c、表生氧化淋滤富集期。  相似文献   

Intraplate mountain building in response to continent–continent collision—the Ancestral Rocky Mountains (North America) and inferences drawn from the Tien Shan (Central Asia)     

Patricia Wood Dickerson   《Tectonophysics》2003,365(1-4):129

The intraplate Ancestral Rocky Mountains of western North America extend from British Columbia, Canada, to Chihuahua, Mexico, and formed during Early Carboniferous through Early Permian time in response to continent–continent collision of Laurentia with Gondwana—the conjoined masses of Africa and South America, including Yucatán and Florida. Uplifts and flanking basins also formed within the Laurentian Midcontinent. On the Gondwanan continent, well inboard from the marginal fold belts, a counterpart structural array developed during the same period. Intraplate deformation began when full collisional plate coupling had been achieved along the continental margin; the intervening ocean had been closed and subduction had ceased—that is, the distinction between upper versus lower plates became moot. Ancestral Rockies deformation was not accompanied by volcanism. Basement shear zones that formed during Mesoproterozoic rifting of Laurentia were reactivated and exerted significant control on the locations, orientations, and modes of displacement on late Paleozoic faults.Ancestral Rocky Mountain uplifts extend as far south as Chihuahua and west Texas (28° to 33°N, 102° to 109°W) and include the Florida-Moyotes, Placer de Guadalupe–Carrizalillo, Ojinaga–Tascotal and Hueco Mountain blocks, as well as the Diablo and Central Basin Platforms. All are cored with Laurentian Proterozoic crystalline basement rocks and host correlative Paleozoic stratigraphic successions. Pre-late Paleozoic deformational, thermal, and metamorphic histories are similar as well. Southern Ancestral Rocky Mountain structures terminate along a line that trends approximately N 40°E (present coordinates), a common orientation for Mesoproterozoic extensional structures throughout southern to central North America.Continuing Tien Shan intraplate deformation (Central Asia) has created an analogous array of uplifts and basins in response to the collision of India with Eurasia, beginning in late Miocene time when full coupling of the colliding plates had occurred. As in the Laurentia–Gondwana case, structures of similar magnitude and spacing to those in Eurasia have developed in the Indian plate. Within the present orogen two ancient suture zones have been reactivated—the early Paleozoic Terskey zone and the late Paleozoic Turkestan suture between the Siberian and East Gondwanan cratons. Inverted Proterozoic to early Paleozoic rift structures and passive-margin deposits are exposed north of the Terskey zone. In the Alay and Tarim complexes, Vendian to mid-Carboniferous passive-margin strata and the subjacent Proterozoic crystalline basement have been uplifted. Data on Tien Shan uplifts, basins, structural arrays, and deformation rates guide paleotectonic interpretations of ancient intraplate mountain belts. Similarly, exhumed deep crustal shear zones in the Ancestral Rockies offer insight into partitioning and reorientation of strain during contemporary intraplate deformation.  相似文献   

Quaternary folding of the eastern Tian Shan, northwest China   总被引：3，自引：0，他引：3  

Bihong Fu  Aiming Lin  Ken-ichi Kano  Tadashi Maruyama  Jianming Guo 《Tectonophysics》2003,369(1-2):79-101

The Tian Shan, east–west trending more than 2000 km, is one of most active intracontinental mountain building belts that resulted from India–Eurasia collision during Cenozoic. In this study, Quaternary folding related to intracontinental mountain building of the Tian Shan orogenic belt is documented based on geologic interpretation and analyses of the satellite remote sensing images [Landsat Thematic Mapper (TM)/Enhanced Thematic Mapper (ETM) and India Remote Sensing (IRS) Pan] combined with field geologic and geomorphic observations and seismic reflection profiles. Analyses of spatial–temporal features of Quaternary folded structure indicate that the early Quaternary folds are widely distributed in both piedmont and intermontane basins, whereas the late Quaternary active folds are mainly concentrated on the northern range-fronts. Field observations indicate that Quaternary folds are mainly characterized by fault-related folding. The formation and migration of Quaternary folding are likely related to decollement surfaces beneath the fold-and-fault zone as revealed by seismic reflection profiles. Moreover, analysis of growth strata indicates that the Quaternary folding began in late stage of early Pleistocene (2.1–1.2 Ma). Finally, tectonic evolution model of the Quaternary deformation in the Tian Shan is presented. This model shows that the Quaternary folding and faulting gradually migrate toward the range-fronts due to the continuous compression related to India–Eurasia collision during Quaternary time. As a result, the high topographic relief of the Tian Shan was formed.  相似文献   

Genetic Modeling of GIS-Based Cell Clusters and Its Application in Mineral Resources Prediction   总被引：2，自引：0，他引：2  

ZhangZhenfei HuGuangdao YangMingguo XiaQinglin JiJinseng GaoFengliang 《中国地质大学学报(英文版)》2003,14(1):85-89,94

This paper presents a synthetic analysis method for multi-sourced geological data from geo-graphic information system (GIS). In the previous practices of mineral resources prediction, a usually adopted methodology has been statistical analysis of cells delimitated based on thoughts of random sam-pling. That might lead to insufficient utilization of local spatial information, for a cell is treated as a point without internal structure. We now take “cell dusters“, L e. , spatial associations of cells, as basic units of statistics, thus the spatial configuration information of geological variables is easier to be detected and utilized, and the accuracy and reliability of prediction are improved. We build a linear multi-discriminating model for the dusters via genetic algorithm. Both the right-judgment rates and the in-class vs. betweewclass distance ratios are considered to form the evolutional adaptive values of the population. An application of the method in gold mineral resoerces prediction in east Xinjiang, China is presented.  相似文献   

遥感影像中分区分类法及在新疆北部植被分类中的应用   总被引：20，自引：8，他引：20  

师庆东  吕光辉  潘晓玲  程维明 《干旱区地理》2003,26(3):264-268

对遥感影像提出了一种分区分类的思想，根据影像所包含的局部特征将整体影像化为几个局部的影像，然后根据局部影像的特点对图像进行分类,使得每一区域的种类数目相对于整体减少，种类的特点得以突出，分类更具有针对性,再加以高程、坡度等地貌信息，提高分类精度。该分类法在新疆北部的植被分类中得到了应用，从NOAA影像中提出的NDVI为数据源，根据该植被区域特点，将研究区的植被区域划分为四个区，即：新疆阿勒泰草原区、昭苏区、西准噶尔区和东天山区。利用GIS软件将整个研究区的NDVI指数图像化分为四块子图，根据各个区域植被的特点，采用不同的分类标准,对四块子图分类。在此之后，再利用GIS软件将所有分类子图合并为整个区域的分类图。结果表明，该类方法可以大大提高NDVI指数的植被分类精度。  相似文献   

新疆北部20年棉花物候计算和分析--以炮台镇为例   总被引：1，自引：2，他引：1  

吕昭智  李莉  田长彦  杨新建  王军  刘永建 《干旱区地理》2003,26(4):340-344

基于single sine物候模型计算新疆北部20年棉花日度累积值，利用系统聚类法分析20年棉花物候变化规律，建立了物候日度和棉花产量之间的回归模型。结果表明：新疆北部棉花主要物候事件播种、出苗、现蕾、开花、裂铃、吐絮和停止生长所需要的日度累积值分别为53．1853．18、109．99、360．97、635．64、1169．61和1180．02日度；聚类分析将20年划分为4个类型即冷年类型、温暖类型、热年和特热年；棉花产量(y)和全年日度累积值(x1)、棉花停止生长日度累积值(x2)和9月份以后的日度累积值(x3)之间存在正相关。  相似文献   

新藏公路新疆段泥石流灾害初探   总被引：2，自引：3，他引：2  

马东涛  崔鹏  杨坤  王掌军 《干旱区地理》2003,26(4):349-354

新藏公路新疆段沿线共有泥石流灾害149处，直接危害线路53．05km。泥石流可分为暴雨型、冰雪融水型及雨水和冰雪融水混合型三个成因类型．其灾害集中分布于哈拉斯坦河、采拉克河、叶尔羌河及喀拉喀什河沿溪线路段。沿线泥石流具有松散堆积物丰富，水源不足，暴发频率低，规模火，受冰川和气候变化影响大等特点。在对泥石流成灾方式、活动现状和发展趋势分析研究的基础上．提出了灾害治理的基本原则和拟采取的主要工程措施及进一步工作的建议。  相似文献   

新疆旅游地域系统及其精品体系建设   总被引：10，自引：10，他引：10  

杨兆萍 《干旱区地理》2003,26(1):57-63

新疆距国际国内客源市场较远，形成一个相对独立的旅游地域系统，只有系统地开发新疆旅游业，才是旅游开发的有效途径。试图从旅游业系统工程角度探讨新疆旅游业最佳的发展模式、空间结构和发展途径。提出应进行客源市场宣传、旅游通道建设、内部精品体系建设全方位的旅游开发建设，并通过实施政府、管理部门、旅游企业、旅游科研教育的连动机制进行旅游业的系统开发和建设。  相似文献   

Geochemical Features of the Two Early Paleozoic Ophiolitic Zones and Volcanic Rocks in the Central —Southern Tianshan Region ,Xinjiang   总被引：2，自引：0，他引：2  

郭建  舒良树  夏飞雅克  卢汉斯巴坦  孙树文 《中国地球化学学报》2002,21(4):308-321

This paper deals with the geochemical features of the two Early Paleozoic ophiolite zones in the central-southem Tianshan region and the central Tianshan igneous rock belt between them.Study results suggest that the central Tianshan belt was an Ordovician volcanic arc with an affinity of continental crust, and the Kumux-Hongluhe ophiolitic zone that is located on the southern margin of central Tianshan has a crustal affinity to back-arc marginal sea.The Aqqikkudug-Weiya ophiolitic zone is an accretionary boundary between the Tuha continental block and the central Tianshan volcanic arc during Late Silurian to Devoniann;Ordovician ophi-olitic blocks,Silurian flysch sequence and HP metamorphic rock relics are distributed along the Aqqikkudug-Weiya zone.Geochemically,ophiolitic rocks in the Aqqikkudug-Weiya zone have an affinity to oceanic crust,reflecting a tectonic setting of paleo-trench or subduction zone .The Early Carboniferous red molasses were deposited unconformably on the pre-Carboniferous meta-mrophosed and ductile sheared volcanic and flysch rocks,providing an upper limit age of the central and southern Tianshan belts.  相似文献