大兴安岭北段塔源二支线铅锌铜矿区岩浆岩岩石成因及其地质意义     

刘宇轩  杨言辰  韩世炯  于秋阳 《世界地质》2022,(1):38-55

塔源二支线铅锌铜矿床地处额尔古纳地块东南缘,位于得尔布干成矿带东段.为确定塔源二支线铅锌铜矿区岩浆岩的岩石成因及其地质意义,对矿区岩浆岩开展了岩石学、地球化学以及同位素年代学研究.笔者在矿区识别出两期岩浆作用,早期发生于(296.1±2.3)Ma(早二叠世),侵入体为二长闪长岩;晚期发生在(136.5±2.1)Ma(早...  相似文献   

正地闪和负地闪预击穿脉冲序列的统计分析与对比     

王宇  郄秀书  王东方  刘明远  王志超 《大气科学》2014,(1)

2009~2010年夏季,在大兴安岭林区利用闪电快、慢电场变化测量仪组成的网络对自然闪电进行了多站同步观测。本文选取2010年夏季3次过境雷暴过程中具有4站以上同步的资料,同时对表现出明显预击穿过程的37次正地闪和56次负地闪的预击穿脉冲序列进行了统计分析。统计的主要参数包括:脉冲序列的总持续时间(Total Duration),脉冲序列和首次回击之间的时间间隔(PB-RS Separation),预击穿过程到首次回击的时间间隔(Pre-RS Interval),单个脉冲持续时间(Individual Pulse Duration),相邻脉冲时间间隔(Interpulse Interval)等。对于负地闪,相应参数的算术平均值为4.1 ms、55.4 ms、56.0 ms、8.8μs和111.0μs,几何平均值为3.7 ms、35.6ms、36.5 ms、7.4μs和98.2μs;对于正地闪,相应参数的算术平均值为4.5 ms、75.6 ms、77.3 ms、11.5μs和297.3μs,几何平均值为3.0 ms、57.8 ms、60.0 ms、10.0μs和217.9μs。对比发现,正地闪预击穿脉冲序列相对负地闪预击穿脉冲序列持续时间更长,和首次回击的时间间隔更大,其单个脉冲更宽,在整个序列中排列更稀疏。计算了正、负地闪最大预击穿脉冲幅值和首次回击幅值的比值(PB/RS,PB代表最大预击穿脉冲幅值,RS代表首次回击幅值),通过和其他研究结果的对比,发现负地闪有PB/RS随纬度增大而增大的趋势,而正地闪没有。另外,检验了首次回击前地闪电场波形与BIL模型(Breakdown Intermediate Leader,BIL)的符合情况,发现只有很小比例的电场波形符合BIL模型。  相似文献   

Effect of Decadal Changes in Air-Sea Interaction on the Climate Mean State over the Tropical Pacific          下载免费PDF全文

FANG Xiang-Hui  ZHENG Fei 《大气和海洋科学快报》2014,(5):400-405

Collaboration of interannual variabilities and the climate mean state determines the type of E1 Nifio. Recent studies highlight the impact of a La Nifia-like mean state change, which acts to suppress the convection and low-level convergence over the central Pacific, on the predominance of central Pacific （CP） E1 Nifio in the most recent decade. However, how interannual variabilities affect the climate mean state has been less thoroughly investigated. Using a linear shallow-water model, the ef- fect of decadal changes of air-sea interaction on the two types of El Nifio and the climate mean state over the tropical Pacific is examined. It is demonstrated that the predominance of the eastem Pacific （EP） and CP E1 Nino is dominated mainly by relationships between anomalous wind stresses and sea surface temperature （SST）. Furthermore, changes between air-sea interactions from 1980-98 to 1999-2011 prompted the generation of the La Ninalike pattern, which is similar to the background change in the most recent decade.  相似文献   

南黄海盆地中部隆起的形成与演化     

杨长清  董贺平  李刚 《海洋地质前沿》2014,30(7):17-21

南黄海盆地是在前震旦系克拉通基础上发育的中、古生界海相与中、新生界陆相多旋回叠合盆地。通过地震资料解释,结合邻区钻井与区域地质资料,对南黄海盆地中部隆起中、古生代地层及其形成演化进行了研究,结果表明,南黄海盆地中部隆起沉积了较全的中、古生界海相地层,发育第四系—新近系、中—下三叠统青龙组、上二叠统、下二叠统—上泥盆统、中—下志留统,奥陶系—震旦系和前震旦系变质岩系等7套地震地质层序;主要经历了前震旦纪基底形成、震旦纪—早古生代克拉通发育、晚古生代—中三叠世稳定台地—陆内裂陷、晚三叠世—古近纪形成与抬升剥蚀及新近纪-第四纪坳陷沉降5个阶段。  相似文献   

Spatial structure of central places in Jilin Central Urban Agglomeration,Jilin Province,China   总被引：1，自引：1，他引：0  

Shijun Wang  Yongchao Wang  Dan Wang 《中国地理科学(英文版)》2014,24(3):375-383

Using the radius of gyration from fractal theory, this paper describes the calculation of fractal dimensions for the four tiers of central places in the Jilin Central Urban Agglomeration(JCUA), Jilin Province, China and the structural characteristics of each tier: 1) the 1st tier central place, Changchun Proper(not including Shuangyang District), provides the most service functions and has the most stable primate position; 2) the 2nd tier central places, Jilin Proper, Siping Proper, Liaoyuan Proper and Songyuan Proper have unclear statuses and do not provide certain functions; 3) the 3rd tier central places comprise 23 county-level cities, counties and urban districts(including Shuangyang District of Changchun), exhibiting a dense spatial structure that agrees with theory; 4) the 4th tier contains the largest number of central places(248 designated towns), but they are loosely distributed. In this study, a spatial image of the JCUA was created, based on vectorized data of the urban settlement distribution, which was then modified and abstracted to create a hexagonal network covering the JCUA. Compared to the traditional central place model, the modified spatial image conforms to the K = 3 principle. In reality, however, the growth of some 3rd tier central places should be increased with the cities being upgraded to the 2nd tier so as to overcome that tier′s functional deficiency. The loose distribution in the 4th tier should also be changed. This apparent anomaly can be explained by the fact that the classic hexagon model used to describe the way market areas layout does not exist in the real world. However, this should not be viewed as an obstacle to using central place theory. If its assumptions are properly applied, it can still assist research into the spatial structure of regions.  相似文献   

我省某铜铅锌矿点地质背景及成矿条件分析     

张猛 《黑龙江国土资源》2014,(8):56-56

叙述地区嘎来奥伊山一带铜铅锌矿点位于大兴安岭北坡嘎来奥伊山一带,行政区划属阿木尔林业局管辖。大地构造位置按黑龙江省地质志划分为西伯利亚板块南缘早加里东增生带北蒙褶皱系东北部的额尔古纳褶皱带。中生代以来本区的地壳演化属古亚洲构造域,新生代以来转入滨太平洋构造域。  相似文献   

欧洲航天局彗星着陆器踏上彗星表面     

《地理教学》2014,(23):60-60

欧洲中部时间12日17时03分,欧航局位于德国达姆施塔特的欧洲空间运转中心收到确认＂菲莱＂着陆的信号。控制室内一片欢呼。＂菲莱＂创造了历史,成为第一个登陆彗星的人造探测器。由于彗星引力小,＂菲莱＂从距离彗星22.5公里的高度降落至彗星表面用了大约7个小时。为防止＂菲莱＂着陆时弹走,科学家们为它设计了三根螺栓和两个＂渔叉＂装置,这些装置将在＂菲莱＂着陆时钉入彗星表面。  相似文献   

基于人类福祉视角的中部地区碳排放绩效与效应分解   总被引：1，自引：0，他引：1  

王圣云  ;史利江  ;许双喜 《世界地理研究》2014,(3):169-176

碳排放绩效是当前国内外低碳经济研究的热点问题,已有研究主要针对经济发展的碳排放绩效测度展开,关注经济产出的碳排放绩效。基于人类福祉是研究碳排放绩效的新视角。首次提出碳排放绩效的概念框架及图解,据此构建了人类福祉的碳排放绩效评估模型,应用LMDI分解法建立了碳排放绩效的效应分解模型,对中部地区人类福祉的碳排放绩效及其效应进行研究发现:(1)1990年~2008年中部六省经济发展的碳排放绩效整体上先增后降;人类福祉的经济绩效与碳排放绩效整体上均呈递减趋同态势。中部地区人类福祉碳排放绩效的省际差距整体上趋向缩小;(2)1990年~2008年中部六省经济发展的碳排放绩效的总效应波动较大,驱动效应和抑制效应交替出现。经济福祉绩效效应整体递增,由抑制效应向驱动效应演进,呈现趋同趋势;(3)中部六省人类福祉的碳排放绩效主要由经济发展的碳排放绩效决定,经济发展的碳排放绩效效应是碳排放绩效总效应的决定性因素,人类福祉的碳排放绩效效应是经济发展的碳排放绩效效应和人类福祉的经济绩效效应两种效应的叠合。  相似文献   

新疆大型煤炭基地建设规划获得国家批复     

钟秀玲 《西部资源》2014,(2)

<正>从新疆维吾尔自治区发改委获悉:近日,国家发改委批复了新疆大型煤炭基地建设规划。根据批复的规划,确定新疆大型煤炭基地由吐哈、准噶尔、伊犁、库拜四大区组成,主要包括36个矿区。吐哈区以疆煤外运和疆电外送为主,准噶尔区以发展煤电、煤化工示范项目为主,伊犁区以发展煤化工示范项目、煤电为主。其他矿区限制开发规模,主要以满足当地发电、城市供热、工业生产用煤和居民生活用煤为主。近期,基地内煤炭主要供应疆内和甘肃等邻近省(区、市),中长期供应川渝和中部地区。  相似文献   

Response to climate change of different tree species and NDVI variation since 1923 in the middle arid region of Ningxia, China     

YaJun Wang  RuiJie Lu  YuZhen M  HongWei Meng  ShangYu Gao 《寒旱区科学》2014,6(1):0030-0036

The normalized difference vegetation index （NDVI） is used extensively to describe vegetation cover and ecological environ- ment change. The purpose of this study was to contrast the response of different tree species growing in the same habitat to climate change and retrieve past NDVI using tree-ring width data from tree cores collected from the transitional zone of Pinus tabulaeformis and Picea crassifolia in the Luoshan Mountains in the middle arid region of Ningxia. Correlation analysis indi- cated that radial growth ofP tabulaeJbrmis is more sensitive to precipitation and temperature change than that ofP crassifolia. Natural factors such as water availability and heat at this elevation are more suited to the growth ofP crassifolia, and are more advantageous to its renewal and succession. P. crassifolia is probably the better of the two species for protecting the forest ecosystem and conserving water in the Luoshan desertification area. Ring width of P. crassifolia correlates significantly with average NDVI for April-May （r =0.641, p 〈0.01）, and both of them are influenced positively by precipitation in April-May. The reconstructed NDVI for 1923-2007 shows the relatively low vegetation cover occurred in the 1920s-1930s, the 1960s-1970s, and the early 21 st century. The reconstructed NDVI better reflected the drought climate in the study area.  相似文献