建库数据快速转换制图数据技术探讨   总被引：1，自引：0，他引：1  

刘小强  邓国庆  陈骏  肖学年  马晓萍 《测绘标准化》2008,(4):18-22

建库数据向制图数据的自动转换问题是测绘生产中比较突出的问题之一,通过空间分析的原理引出符号空间的描述,为符号冲突探测提供新思路,并给出符号冲突消解原则和方法,为解决这一难题提供参考。  相似文献   

利用GPS形变资料研究天山及邻近地区地壳水平位移与应变特征   总被引：15，自引：1，他引：15       下载免费PDF全文

王晓强  李杰  王琪 《地震学报》2007,29(1):31-37

以天山及邻近地区的230个GPS观测站长期水平运动速率为基础， 计算并绘制了该地区GPS站速度场及地壳水平应变场分布图， 得到了以下结论: 在以欧亚板块为参考基准的背景下， 天山及邻近地区GPS速度场表明， 天山地壳缩短方式由南向北， 以东经77deg;plusmn;1deg;（北纬38deg;~42deg;）为界向两侧逐渐递减； 同时表明，板块的推挤作用力随着天山的褶皱变形减小相应趋缓. 天山及邻近地区的主压应变方向分布近北北西向， 基本与天山山体走向正交. 反映了在印度板块碰撞推挤的强烈构造运动影响下天山及邻近地区的最大主应力分布与变化情况. 其最大剪应变场集中分布在两个区域: 北天山的吉尔吉斯斯坦依赛克湖附近； 南天山伽师与帕米尔弧形断裂交会地带. 整个地区多年来的地震震中分布, 反映了该区域大地震通常发生在剪应变高值区或其边缘地带.   相似文献   

国土资源调查数据地图综合狭长图斑的中剖分处理     

徐海江  成晓强  艾廷华 《北京测绘》2021,35(3):358-363

国土资源调查获得的土地利用图在服务不同层次、不同级别国土规划管理应用中,面临着多级数据库建设与地图综合缩编的任务需求.土地利用图中狭长图斑的中轴化是其中不可缺少的关键操作之一.针对土地利用数据全覆盖、无重叠、无缝隙及语义上多层次的特点,本文提出一种密集覆盖多边形数据的中轴化处理与拓扑关系维护的方法,用“剖分”与“归并”的思想模拟邻域多边形的扩张过程.本文算法实现建立在Delaunay三角网数据结构上,兼顾了语义相似关系的影响,经第三次国土资源调查成果的检验,本文所述中轴化及拓扑维护方法能够满足土地利用图综合实际生产的需要.  相似文献   

西天山克细克红那海银铜矿地质特征及成因初探     

伏多旺  杨小强 《新疆地质》2015,(1):73-77

克细克红那海银铜矿位于阿吾拉勒-伊什基里克金、银、铜、铅、锌(铁)锰成矿带西段,成矿地质条件优越。通过对矿床地质特征及成因的初步总结分析,认为矿化赋存与下石炭统大哈拉军山组第三段玄武粗面安山岩、粗面安山岩、凝灰质砂岩中,受近EW向和近NS向断裂控制,经多期热液成矿作用叠加成矿,属中低温热液充填型矿床。  相似文献   

西藏冈底斯带中段南木林县仁堆侵入体LA-ICP-MS锆石U-Pb年龄及岩石成因   总被引：1，自引：1，他引：0  

卜涛  魏启荣  丁鹏飞  王程  刘小念  张小强  孙骥  王敬元 《地质通报》2015,34(12):2254-2265

对冈底斯带中段仁堆地区二云母花岗岩进行LA-ICP-MS锆石U-Pb定年,主量和微量元素地球化学分析表明,二云母花岗岩的结晶年龄为226.3±0.98Ma。二云母花岗岩为高钾钙碱性强过铝质花岗岩,Si O2含量为72.83%~74.99%,K2O/Na2O为1.58~2.37,Alk为7.37%~8.72%,A/CNK为1.21~1.39(1.1),刚玉标准分子ω(C-norm)大于1%。稀土元素总量为61.71×10-6~175.16×10-6,其中,轻稀土元素总量为53.93×10-6~165.49×10-6,重稀土元素总量为7.588×10-6~13.880×10-6,轻、重稀土元素分馏明显,(La/Yb)N介于10.49~42.170之间。在稀土元素配分模式图上,表现为轻稀土元素富集的右倾型,有明显的负Eu异常,δEu介于0.264~0.57之间;在微量元素蛛网图上,表现出Ba、Nb、Sr、Ti、P亏损和Rb、K、U富集的特征。二云母花岗岩是增厚的冈底斯地壳在印支晚期应力松弛阶段,由于构造减压诱发部分熔融形成的。  相似文献   

Carbon isotope fractionation during low temperature carbonization of foxtail and common millets     

Qing Yang  Xiaoqiang Li  Weiguo LiuXinying Zhou  Keliang ZhaoNan Sun 《Organic Geochemistry》2011,42(7):713-719

Stable carbon isotopes of organic matter and fossilized plant remains can be used to effectively reconstruct local palaeoclimate changes, especially from plants using a single photosynthetic mode. The charred grains of foxtail and common millet are chemically stable in the environment and have been preserved widely and continuously throughout the Holocene in North China. The charred remains of these species are ideal materials for reconstructing the palaeoclimate based on δ¹³C of foxtail and common millets heated to temperatures up to around 250 °C. This study reports δ¹³C values of modern millets carbonized at different temperatures. The results indicate that there are no significant changes in δ¹³C of intact and charred samples of foxtail millet (?0.46‰) and common millet (?0.49‰) for temperatures below 300 °C. The δ¹³C of charred foxtail millet formed at 250 °C were 0.2‰ higher in δ¹³C than the source samples. In contrast, the δ¹³C of charred common millet formed at 250 °C were 0.2‰ lighter in δ¹³C than the source samples. The δ¹³C values of grains were determined in part by the carbon content (i.e., starches, lignins and lipids) and the variable thermal tolerances of these compounds to heating. However, the observed ¹³C carbonization associated with fractionation of only 0.2‰ in grains is much less than the natural variation typically found in wood. We therefore suggest that δ¹³C measured in carbonized grains can serve as an effective indicator for paleoenvironmental and archaeological reconstructions.  相似文献   

Modern pollen distributions in Qinghai-Tibetan Plateau and the development of transfer functions for reconstructing Holocene environmental changes   总被引：2，自引：0，他引：2  

Houyuan Lu  Naiqin Wu  Kam-biu Liu  Liping Zhu  Xiangdong Yang  Tandong Yao  Luo Wang  Quan Li  Xingqi Liu  Caiming Shen  Xiaoqiang Li  Guobang Tong  Hui Jiang 《Quaternary Science Reviews》2011,30(7-8):947-966

This study investigates the distribution of modern pollen assemblages in the Qinghai-Tibetan Plateau, China, based on surface soil samples collected at 1202 sites along an altitudinal gradient of 10–5500 m asl, where mean annual precipitation (MAP) ranges from 12 to 1840 mm and mean annual temperature (MAT) from ?7 to 21.5 °C. A total of 153 pollen taxa were found with relative abundances greater than 1% in at least two samples. Canonical correspondence analysis (CCA) was used to determine the main environmental variables influencing pollen distributions. The results reveal that MAP is the most significant dominant variable. However, MAT, altitude (ALT), July temperature (MT7), and relative humidity (HHH) are also significant variables that clearly follow the gradients in the CCA ordination, suggesting that pollen assemblages probably not only reflect a single climatic parameter, but also a variety of other climatic inter-related parameters.Transfer functions, based on locally weighted weighted averaging (LWWA), were developed for MAP (R²-boot = 0.89, RMSEP = 109 mm), MAT (R²-boot = 0.78, RMSEP = 2.3 °C), ALT (R²-boot = 0.73, RMSEP = 597 m), HHH (R²-boot = 0.82, RMSEP = 4.5%), and July mean precipitation (MP7) (R²-boot = 0.87, RMSEP = 23 mm). Overall, our results confirm that pollen can provide reliable estimates of the primary climatic parameters. The application of the LWWA model to the fossil records of Chen Co Lake allowed quantitative inferences to be made about Holocene climatic changes in the southern Tibetan Plateau, suggesting that LWWA is a robust calibration method for quantitative palaeo-environmental reconstruction based on pollen data in the regions.  相似文献   

Middle Holocene hunting-gathering culture and environmental background of the steppe area of northern China     

Ma  Jiacheng  Zhou  Xinying  Yang  Shixia  Rao  Huiyun  Li  Jiaoyang  Hu  Songmei  Yang  Yimin  Li  Xiaoqiang 《中国科学:地球科学(英文版)》2022,65(7):1317-1327

Science China Earth Sciences - For a long time, the academic community has known very little about hunter-gatherers in the steppe area of northern China in the mid-Holocene. This article reports on...  相似文献   

云南东川铜矿床流体演化与成矿机制研究     

曾瑞垠  姜华  祝新友  张雄  肖剑  吕晓强  胡川  杨晓坤  李金林  郑泽光 《现代地质》2021,35(1):244-257

东川铜矿床是我国重要的沉积岩容矿的层状铜矿床(SSC),具有显著的多层位成矿特征和典型的铜硫化物分带。本研究以不同层位铜矿体的流体包裹体为研究对象,通过岩相学观察、显微测温和激光拉曼成分分析,发现东川群多层位铜矿体存在浅色和深色包裹体2种类型:浅色包裹体成分以H₂O为主,含丰富的石盐子晶和少量钾盐、硬石膏子晶,代表了氧化型含矿卤水,具中低温(140~300 ℃)、中高盐度(12%~44%)的特征,属于Na ⁺、K ⁺、Ca ²⁺-Cl ^-(SO₄ ^2-)型盆地卤水,主要来源于海相蒸发岩的溶解和层间建造水;深色的含有机质包裹体代表了还原型流体,来源于黑山组碳质板岩和落雪组中的藻类生物分解。东川铜矿床以落雪组的含叠层石砂质白云岩作为主要沉淀系统,黑山组碳质板岩为隔挡层,形成一个流体封闭的物理化学圈闭,氧化含矿卤水通过供给系统运移到具还原性质的沉淀系统中,与还原型富硫流体和含有机质的地层发生混合反应,形成多层位的层状铜矿体和层控脉状铜矿体。  相似文献   

北淮阳汞洞冲铅锌矿区石英正长斑岩成因   总被引：1，自引：0，他引：1  

刘晓强  闫峻  王爱国 《地质学报》2018,92(1):41-64

汞洞冲铅锌矿位于北淮阳构造带安徽段的西部,是大别造山带目前发现的最大铅锌矿。该矿床为典型的隐爆角砾岩型,成矿流体具有岩浆来源特征。野外地质调查显示隐爆作用与孙冲出露的石英正长斑岩有关。两个采自孙冲石英正长斑岩体样品的LA-ICPMS锆石U-Pb定年结果分别为128.4±1.3 Ma和129.2±1.2Ma,为早白垩世岩浆活动的产物。这些石英正长斑岩样品具有较高的SiO_2含量(62.04%~69.30%),富K_2O(4.54%~7.16%,K_2O/Na_2O=0.94~2.86),富碱(K_2O+Na_2O=8.76%~10.01%),铝碱比值(A/NK)在1.17~1.97之间,铝饱和指数(A/CNK)介于1.03~1.59之间,属过铝质岩石,富集Rb、Th、U、Pb等大离子亲石元素、亏损Nb、Ta、P和Ti等高场强元素。岩石具有高度富集的Sr-Nd-Pb-Hf同位素组成:全岩~(87)Sr/~(86)Sr(t)介于0.71129~0.71323之间,ε_(Nd)(t)值介于-10.8~-9.8之间,~(206)Pb/~(204)Pb(t)比值为17.495~17.891,~(207)Pb/~(204)Pb(t)比值为15.526~15.593,~(208)Pb/~(204)Pb(t)比值为38.257~38.547,绝大多数锆石ε_(Hf)(t)值介于-17.1~-10.4。综合地球化学研究表明,该石英正长斑岩的岩浆源区类似于中、南大别片麻岩为代表的大别造山带三层地壳结构的上部,有少量的幔源物质贡献。华南板块广泛分布的古生代黑色岩系在印支期深俯冲过程中被剥蚀至北淮阳地壳深部,构成北淮阳成矿岩浆岩的理想源区。  相似文献