近10年来城市地质学研究和城市地质工作进展述评   总被引：3，自引：0，他引：3  

金江军  潘懋 《地质通报》2007,26(3):366-370371

首先回顾了近10年来城市地质学研究的进展。国际上,城市地质学研究主要集中在城市地质与城市规划的结合、城市地质环境和灾害风险评价等方面,国内则集中在城市地质调查方法、城市地质灾害防治方法等方面。然后回顾了近10年来城市地质工作的情况。国际上,建立城市地质环境动态监测体系是一个新动向。在国内,城市地质调查仍然是今后很长一段时间的工作重点。最后针对目前存在的问题提出了若干对策:城市地质学研究要结合城市发展过程中面临的重大问题,积极运用现代信息技术,大力培养专业人才,主动为城市规划建设服务,编制城市地质工作专项规划,建立城市地质工作成果流通机制等。  相似文献   

1944-2005年黑河流域径流量变化特征及趋势(英文)     

王钧  蒙吉军 《地理学报(英文版)》2007,(3)

The Heihe River drainage basin is one of the endangered ecological regions of China. The shortage of water resources is the bottleneck,which constrains the sustainable development of the region. Many scholars in China have done researches concerning this problem. Based on previous researches,this paper analyzed characteristics,tendencies,and causes of annual runoff variations in the Yingluo Gorge (1944-2005) and the Zhengyi Gorge (1954-2005),which are the boundaries of the upper reaches,the middle reaches,and the lower reaches of the Heihe River drainage basin,by wavelet analysis,wavelet neural network model,and GIS spatial analysis. The results show that: (1) annual runoff variations of the Yingluo Gorge have principal periods of 7 years and 25 years,and its increasing rate is 1.04 m3/s·10y; (2) annual runoff variations of the Zhengyi Gorge have principal periods of 6 years and 27 years,and its decreasing rate is 2.25 m3/s·10y; (3) prediction results show that: during 2006-2015,annual runoff variations of the Yingluo and Zhengyi gorges have ascending tendencies,and the increasing rates are respectively 2.04 m3/s·10y and 1.61 m3/s·10y; (4) the increase of annual runoff in the Yingluo Gorge has causal relationship with increased temperature and precipitation in the upper reaches,and the decrease of annual runoff in the Zhengyi Gorge in the past decades was mainly caused by the increased human consumption of water resources in the middle researches. The study results will provide scientific basis for making rational use and allocation schemes of water resources in the Heihe River drainage basin.  相似文献   

超高压榴辉岩中金红石的纳米级微构造特征及成因机制探讨   总被引：3，自引：4，他引：3  

陈晶许志琴  李旭平 《岩石学报》2005,21(2):399-404

本文应用透射电子显微镜(TEM)详细研究了,中国苏鲁毛北地区金红石榴辉岩中金红石的超微构造特征。在该金红石榴辉岩中发育有两种不同类型的金红石晶体。第一种类型的金红石(Rt(A))与石榴石和绿辉石共生,其晶体内部发育有极密集的晶体缺陷,调制结构和变形双晶。变形双晶面分别为(100)和(010)。表明该类金红石晶体曾遭受过强烈的应力作用,推测它们可能是在大陆板块俯冲或折返过程中形成中发育的。而另一类金红石(Rt(B))存在于石榴石和绿辉石晶体中的包体,其晶格十分完整,没有变形痕迹。可能是由于该类金红石寄主于较大颗粒的石榴石或绿辉石晶体中,在大陆板块俯冲或折返过程中因受到寄住主晶的保护,没有发生晶格畸变。  相似文献   

中国阿尔泰造山带后造山喇嘛昭花岗岩体锆石SHRIMP年龄、成因及陆壳垂向生长意义   总被引：41，自引：29，他引：41  

王涛  洪大卫童英韩宝福  石玉若 《岩石学报》2005,21(3):640-650

喇嘛昭岩体是阿尔泰造山带典型的后构造岩体,其时代问题一直没有解决。本次锆石SHRIMP定年给出 206Pb／238U年龄276±9Ma(MSWD=1．1),代表其形成年龄。这为阿尔泰后造山花岗岩和后造山作用提供了一个可靠的年代学证据。主量、微量元素地球化学特征显示该岩体具有I-A过渡的高钾钙碱性或高分异钙碱性花岗岩的特点。依据岩体构造特征、年代学、地球化学和地质背景综合分析,该岩体应为后造山岩体。该岩体Sr初始值变化于0．704-0．71659之间。εNd(T) 值为正值( 1．3- 2．8),模式年龄TDM-2为0．93-0．81Ga,与中亚造山带典型的高(正)εNd(T)值花岗岩相同。而且,其εNd (T)值略高于该地区同造山花岗岩。这说明,在具有陆壳基底的阿尔泰造山带后造山阶段,除了可能的俯冲下埋的年轻洋壳或岛弧物质外,可能有新的幔源物质参与了花岗岩的形成。这为中亚造山带后造山阶段陆壳垂向生长提供了一个证据。  相似文献   

喜马拉雅山佩枯岗日冰川地貌的年代学、平衡线高度和气候研究   总被引：8，自引：6，他引：2  

刘耕年  Li Yingkui  陈艺鑫  张梅  李川川  孔屏  Harbor J.  Caffee M.W. 《冰川冻土》2011,33(5):959-970

喜马拉雅山珠穆朗玛峰-希夏邦马峰地区是青藏高原南部现代冰川集中发育区之一,古冰川遗迹亦十分丰富,是研究第四纪青藏高原冰川形成和演化的关键区,一直备受地貌和第四纪环境研究者的关注.应用原地宇宙核素10Be暴露年龄测试技术,对采自希夏邦马峰西北佩枯岗日拉曲谷地冰碛垄上的冰川漂砾进行年代学研究;结合冰川地貌分析方法,对古冰川...  相似文献   

Re-Os and U-Pb Geochronology of the Erlihe Pb-Zn Deposit,Qinling Orogenic Belt,Central China,and Constraints on Its Deposit Genesis   总被引：4，自引：0，他引：4  

ZHANG Fan  LIU Shuwen  LI Qiugen  SUN Yali  WANG Zongqi  YAN Quanren  YAN Zhen Key Laboratory of Orogenic Belt  Crustal Evolution  Ministry of Education  Peking University  Beijing  China Guangzhou Institute of Geochemistry  Chinese Academy of Sciences  Guangzhou  China Institute of Mineral Resources  Chinese Academy of Geological Sciences  Beijing  China Institute of Geology  China 《《地质学报》英文版》2011,(3)

The Erlihe Pb-Zn deposit is an important mine of the Pb-Zn metallogenic zone in the South Qinling Orogen.It has been considered a sedimentary exhalative deposit in previous investigations because the ore body occurs concordantly at the transitional location of an upright fold.Re and Os isotopic analyses for paragenetic pyrites with sphalerite and galena from the ore body have been used to determine the timing of mineralization and to trace the source of metallogenic materials.The Re-Os isotopic data of f...  相似文献   

Pulsating magneto-dipole radiation of a quaking neutron star powered by energy of Alfvn seismic vibrations     

Sergey Bastrukov  Irina Molodtsova 《中国天文和天体物理学报》2011,(9)

We compute the characteristic parameters of the magneto-dipole radiation of a neutron star undergoing torsional seismic vibrations under the action of Lorentz restoring force about an axis of a dipolar magnetic field experiencing decay.After a brief outline of the general theoretical background of the model of a vibration-powered neutron star,we present numerical estimates of basic vibration and radiation characteristics,such as frequency,lifetime and luminosity,and investigate their time dependence on magn...  相似文献   

Anchimetamorphism of the Neoproterozoic and the Lower Paleozoic along the Profile of Yuanguping in Western Hunan Province, China   总被引：3，自引：0，他引：3  

WANG Hejing  CHEN Tao  WANG Huan  ZHANG Zuqing"Orogene  Crust Evolution " Key Laboratory of the Ministry of Education of Chin  School of Earth  Space Sciences  Peking University  Beijing 《《地质学报》英文版》2004,78(1):170-176

The Neoproterozoic and Lower Paleozoic along the profile of Yuanguping in western Hunan Province, China underwent anchimetamorphism. The illite crystallinity (IC) of the <2 μm fractions ranges from 0.23-0.34°△2θfor the Neoproterozoic to 0.23-0.35°△A2θ for the Lower Paleozoic (calibrated with the Kisch IC set, Kisch, 1991). This indicates that the metamorphic grade of the Neoproterozoic and Lower Paleozoic is the anchizone. The peak metamorphic temperature is estimated to be 290-210℃. This result does not agree with the greenschist or subgreenschist facies of the Banxi Group, nor with the lower-greenschist facies or sedimentary cover of the Sinian to Lower Paleozoic, as most previous researchers thought. The illite (K-mica) b0 values range from 0.9074 to 0.8963 (nm) for the Neoproterozoic and the Lower Paleozoic. Based on cumulative frequency curves of the illite (K-mica) b0, the peak metamorphic pressure of the Banxi Group was derived to be of a type that is slightly higher than that of the N. Ne  相似文献   

Postcranial Anatomy of the Mesozoic Dalinghosaurus (Squamata): Evidence from a New Specimen of Western Liaoning     

JI Shu''an  JI Qiang School of Earth  Space Sciences  Peking University  Beijing Institute of Geology  Chinese Academy of Geological Sciences  Beijing 《《地质学报》英文版》2004,78(4):897-906

The postcranial skeleton of a new specimen of the long-tailed lizard Dalinghosaurus longidigitus was excavated from the Yixian Formation in Lingyuan, western Liaoning. The new specimen provides more anatomical information about this species, especially about the anterior dorsal vertebrae, shoulder girdle and forelimbs. This lizard can be included within the clade Scleroglossa by its 27 or more presacrals, moderately long pubis, and gently notched distal end of tibia. But the detailed systematic position for this taxon remains undetermined. The features of the much longer hind limbs and pes compared with forelimbs and manus, metatarsal Ⅳ longer than Ⅲ, pedal phalanges robust, and penultimate phalanx not longer than other phalanges etc. suggest that this lizard was a running and ground swelling animal.  相似文献   

Indosinian Tectonic Setting of the Southern Yidun Arc： Constraints from SHRIMP Zircon Chronology and Geochemistry of Dioritic Porphyries and Granites   总被引：2，自引：0，他引：2  

LIU Shuwen  WANG Zongqi  YAN Quanren  LI Qiugen  ZHANG Dehui  WANG Jianguo  YANG Bin  GU Libing  ZHAO Fengshan The Key Laboratory of Orogenic Belts  Crustal Evolution  Ministry of Education  School of Earth  Space Sciences  Peking University  Beijing 《《地质学报》英文版》2006,80(3):387-399

A mass of granitoid and dioritic intrusions are distributed in the southern Yidun Arc, among which the representative Indosinian intrusions include the Dongco and Maxionggou granitoid intrusions in Daocheng County and hypabyssal intrusions intruding into arc volcanic rocks near the Xiangcheng town. The Dongco and Maxionggou granitoid intrusions consist mainly of porphyraceous monzogranites, megacryst monzogranites and aplite granites. The Xiangcheng hypabyssal intrusions are composed dominantly of dioritic porphyries. SHRIMP zircon ages of 224±3 Ma and 222±3 Ma have been obtained for the Dongco granitoid intrusion and the Xiangcheng dioritic porphyries, respectively. The Xiongcheng dioritic porphyries show a cak-alkaline geochemical feature, and are characterized by higher Sr/Y ratios, depletive Nb, Ta, P and Ti, enriched LILEs, and lower εNd (t) (= -3.27), suggesting that they might be derived from mantle source magmas that were obviously contaminated by continent crustal materials. However, the Dongco and Maxionggou granitoids belong to high-potassium calc alkaline series with a per-metaluminous feature, and are characterized by higher CaO/(∑FeO+MgO) and Al2O3/(∑FeO+ MgO) ratios, lower (La/Yb)n and Sr/Y ratios, depletive Nb, Ta, Sr, P and Ti, enriched LILEs, and very low εNd (t) (= -8.10), indicating that the granitoids might be derived from partial melting of continental crust materials mainly of graywacke. Petrogenesis of Dongco and Maxionggou granitoids implies that there was an oceanic crust between the Zongza continental block (ZCB) and western margin of the Yangtze Craton (WMYZC). And the oceanic crust slab subducted westward during the Indosinian Epoch, producing an Andes-type continent marginal arc and a back arc basin at the WMSCC. Then the oceanic basin closed and a sinistrally lateral collision occurred at ca. 224 Ma-222 Ma between the ZCB and the WMYZC, causing partial melting of sediments in the back-arc basin to generate granitoid magmas of the Dongco and Maxionggou intrusions.  相似文献