表碛覆盖型冰川的提取方法及变化

表碛覆盖型冰川是山地冰川的一种特殊类型,表碛的存在使得其对气候变化呈现出不同的响应特征。基于2011—2020年Landsat TM/ETM+/OLI遥感影像和ASTER DEM数据,在综合分析表碛光谱、地形和地表温度特征基础上提出TDSI(temperature NDDI slope ice)方法,并将其用于提取中国境内托木尔冰川等6条大陆型冰川和雅弄冰川等3条海洋型冰川。结果表明：基于TDSI方法提取表碛覆盖型冰川的总体精度为91.23%,其中大陆型和海洋型表碛覆盖冰川的精度分别为91.20%和90.97%。2011—2020年6条大陆型冰川和3条海洋型冰川面积平均减少0.06%和0.11%,而表碛面积分别增加了11.92%和18.35%。大陆型冰川表碛主要分布在其中值海拔以下,而海洋型冰川表碛分布范围更广,近10年间二者均呈现向冰川上部扩张趋势。气温上升是冰川消融退缩和表碛增加的主要原因,同时冰川流速变化和终碛湖演变也对表碛变化有一定影响。     

近40年来塔里木河流域气候及径流变化特征研究

以塔里木河流域的21个气象站和10个水文站1961～2000年观测资料为基础,对塔里木河流域的温度、降水及径流变化进行了分析.结果得出:(1)20世纪60年代以来塔里木河流域的年平均气温呈逐年代递增趋势,源流区的年平均气温增高了0.57℃,上游区增高了0.6℃,中游区增高了0.7℃,下游区增高了0.8℃,越往下游方向变暖趋势越明显,并且气温增高幅度逐步加大.(2)60年代以来塔里木河流域的年降水量也逐年递增,但是与温度的增幅趋势相反,从源流区到下游区,降水增幅逐步减少,源流区平均增加了34.2%,上游区增加了22.0%,中游区增加了15.3%,下游区只增加了6.1%.(3)该流域各源流的出山口径流量除和田河减少外,阿克苏河增加9.04亿m3,叶尔羌河增加5.51亿m3,开都河增加9.27亿m3.(4)该流域源流径流受温度和降水变化的双重影响,源流区的气候变暖和变湿是塔里木河源流径流量增长的一个非常重要的因素.     

国外海洋岩石圈深部结构的地震学研究进展

近十年来,深地震反射波勘探在海洋岩石圈的形成与演化,地壳结构研究中的应用越来越广泛,本文介绍了美,英,法及北欧一些国家在北海,波罗的海,挪威海,大西洋,太平洋,地中海等海域分别进行的垂直入射,宽角反射／折射地震试验,及其在大陆边缘构造,海洋地壳的演化,海底断裂形态,性质等方面的研究成果。     

Pre-collision Granites and Post-collision Intrusive Assemblage of the Kelameili-Harlik Orogenic Belt

The main types of intrusive rocks in the Kelameili-Harlik Hercynian erogenic belt include calc-alkaline granites, diabase dykes, kaligranites and alkaline granites. Investigation in field geology, petrology, mineralogy and geochemistry shows that the calc-alkaline granites belong to the syntexis-type (or I-type) and were formed in a pre-collisional magmatic arc environment. In consideration of the fact that kaligranites have many features of alkaline granites with higher consolidation temperatures than the calc-alkaline granites and show a discontinuity of minor element and REE evolution in respect to the calc-alkaline granites, they could not have been derived by differentiation of magmas for the calc-alkaline granites, but are likely to have been generated in an environment analogous to that for alkaline granites. The triplet of basic dyke swarms, kaligranites and alkaline granites could be regarded as a prominent indication of the initial stage of post-collisional delamination and extension. These ro     

The spatial dynamics of foreign investment in the Pearl River Delta, south China

The Pearl River Delta region in south China has experienced dramatic economic development, industrialization and urbanization since the late 1970s. Foreign investment, especially the capital from Hong Kong, has been one of the major driving forces underlying the process. The spatial concentration/diffusion of foreign investment in a region also has important bearing on the balanced/unbalanced urban and regional development. This issue remains unexamined and critical analysis is needed to unveil the spatial impacts of foreign direct investment (FDI) activities in China. This paper will focus on the Pearl River Delta region to examine the spatial diffusion and the determinants of foreign investment. The diffusion of foreign investment from the provincial capital, Guangzhou and two special economic zones near Hong Kong to surrounding areas is clearly identified. The diffusion is the result of the widespread implementation of open-door policy in the region and significant improvement in infrastructure. Four models of foreign investment are developed to explain the spatial incidence of foreign investment in the region. The findings of this paper can shed light on the regional development process in China and other developing countries under the influence of foreign capital.     

改革开放以来广东省空间极化研究

改革开放２０年来广东省的空间结构演化表明：传统的核心－边缘模式已发生了很大的变化,区域出现多极化且次级核心区形成。广州华南中心城市的地位已经被香港所取代,韶关、湛江、汕头、潮阳等老中心城市地位不断下降,深圳、珠海、东莞、中山、顺德、南海和番禺等新兴城市正发展成为新区域增长中心。珠江三角洲经济发展开始向外围地区扩展,出现了反极化的趋势。全省空间差异扩大,形成了多层次的空间极化格局。     

GPS天线相位中心偏差的数学模型

叙述了天线相位中心的检测方法．改进了GPS天线相位中心偏差的数学模型．在不考虑天线相位中心随卫星高度、方位角变化时该模型可以准确地计算出天线相位中心水平偏差大小与方向和垂直偏差的大小,从而提高了天线相位中心偏差的确定精度。实例表明,本文所提出的方法可以较准确地判断出天线相位中心水平偏差的大小与方向。     

华北北部大型-超大型矿床的特征及其形成的宏观地质背景

华北北部经历了太古宙－元三宙克拉通基底形成演化、中新元古宙裂谷作用、古生代“软”造山中生代伸展构造体制以及新生代盆－岭构造演化。中元古宙和中生代是华北北缘的两个大规模成矿时期华北中段从南往北依次公布关：华北克拉通北缘Ａｕ－Ｃｕ矿化集中区;大兴安岭Ｃｕ－Ｓｎ多金属矿化集中区;北邻蒙古和俄罗期境风Ｆｅ－Ａｕ－Ｕ－ＷＳｎ（Ｍｏ,Ｂｅ）集中分布。Ｍｏ矿化主要出现在克拉通内部,Ｓｎ矿化主要出现在大兴安岭地区     

安徽铜陵地区铜金矿化关系及其成因初探

铜陵地区是长江中下游成矿带中重要的铜金成矿区之一,区内已发现数十处铜、金矿床,二者间的关系主要表现为:矿床类型有铜矿床、金矿床和铜金(或金铜)矿床,空间上有内铜外金、下铜上金、西铜东金(左铜右金)分布规律,时间上金矿化一般晚于铜矿化.本文从金、铜地球化学性质及成矿过程中物理化学条件的变化对成矿作用的影响等方面初步探讨了二者间存在上述关系的成因,以期对该区及相似地区找矿有所启迪.     

桶基平台负压沉贯施工机具的研究与应用

桶形基础采用负压沉贯方法施工, 初始入泥和倾斜控制成为制约桶形基础平台应用于浅水区的重要环节.通过分析沉贯、倾斜调整机理,设计了1种负压沉贯施工机具,并成功应用于CB20B桶形基础平台的海上安装,对浅水区桶形基础平台施工机具研究开发具有指导意义.