季节性冻土区水文特性及模型研究进展   总被引：6，自引：1，他引：5  

王晓巍  付强  丁辉  李天宵 《冰川冻土》2009,31(5)

简要评述了寒区冻土水文的研究进展情况,在分析季节性冻土的冻融水文过程和特点的基础上,系统归纳与总结了季节性冻融土壤条件下的融雪径流的产流模型、入渗规律及预报模型、对非寒区水文模型改进后应用到寒区的探讨及定量研究冻土水分迁移运动的数值模拟方法,并提出未来研究方向:开发更加逼近真实情况的水文水利模型;野外大田实验数据的监测采集并确定水文模型的参数;将水文模型与冻土水分迁移模型的完善结合.  相似文献   

巴基斯坦达尔巴丁(Dalbandin）地震前观测到的电离层foF2异常变化     

穆罕默德?伊尔凡  阿夫塔?阿拉姆  默罕默德?朱奈德  默罕默德?埃亚茨?阿明  达拉?伊克巴尔  黄辅琼 《中国地震研究》2015,29(4):567-575

电离层foF2变化对地震反应非常敏感,与地震有关的电离层扰动变化结果似乎非常有望用于地震短期预测。格林威治时间2011年1月18日20:23分,一次7.2级的大地震发生在巴基斯坦的达尔巴丁(28.73oＮ, 63.92oＥ）。本文研究中,我们必须利用架设在巴基斯坦的伊斯兰堡（33.78oN, 73.06oE）、玛尔坦（32.26oN,71.51oE）和卡拉奇（24.89oN,67.02oE）三个垂直探测台站获得的白天（08:00 a.m. - 05:00 p.m.）小时值数据找出地震前的foF2异常变化特征。结果显示,在达尔巴丁地震前几天,foF2出现了显著变化;并且距离震中最近的台站观测到的频率与幅度异常变化大于较远的位于孕震区边缘的台站。尽管地震异常特征显著,但增加其它电离层参数可以提高foF2异常的高置信度水平。  相似文献   

西藏首例云英岩型钨矿——甲岗雪山W-Mo多金属矿床地质特征研究     

徐培言  郑远川  付强  杨竹森  沈阳  马睿  王梓轩  吴昌 《岩石矿物学杂志》2017,36(2):227-240

甲岗雪山W-Mo多金属矿床位于西藏自治区申扎县境内,地处冈底斯北部,成矿时代为中新世。矿床与矿区内的二长花岗岩体时空关系紧密,矿区内的围岩蚀变普遍见云英岩化,并且云英岩化强烈的地方多伴随强烈的钨钼矿化;矿体的类型以云英岩型为主,还有少量石英脉型,矿石又多呈细脉状或浸染状赋存于云英岩或云英岩化二长花岗岩体内部,证实了矿床的成因类型为云英岩型。依据野外见到的矿物共生组合、脉体穿切关系等,可将成矿期划分为硅酸盐-氧化物阶段和硫化物阶段。流体包裹体研究表明,甲岗雪山W-Mo多金属矿床主成矿期的成矿流体为中-高温、中-低盐度的流体,从主成矿期的硅酸盐-氧化物阶段演化到硫化物阶段,成矿流体的温度下降明显,盐度也有所下降。  相似文献   

Organic-walled Microfossils from the Early Middle Cambrian sediments of the Holy Cross Mountains, Poland: Possible Implications for Sedimentary Environment in the SE Margin of the Baltica     

Marta B?K  Lucyna NATKANIEC-NOWAK  Beata NAGLIK  Krzysztof B?K  Pawe? DULEMBA 《《地质学报》英文版》2017,91(1):39-50

An association of organic-walled microfossils consisting of filamentous cyanobacteria, algal coenobia and acanthomorphic acritarch have been documented from non-calcareous claystones and mudstones of the Pepper Mountains Shale Formation(PMSF), located in its stratotype area in the Pepper Mountains, which are part of the Holy Cross Mountains in Poland. These sediments represent the oldest strata of the ?ysogóry Unit, deposited on the edge of the East European Craton(Baltica). Non-branched, ribbon-like and thread-like cyanobacteria trichomes exhibit morphological similarities to families Nostocaceae and Oscillatoriaceae. Cells assembled in rounded to irregular clusters of monospecific agglomerations represent multicellular algal coenobia, attributed to the family Scenedesmaceae. The co-occurrence of acritarchs belonging to species as Eliasum llaniscum, Cristallinium ovillense and Estiastra minima indicates that the studied material corresponds to the lower Middle Cambrian. Deposition of the PMSF took place in shallow marine environment, influenced by periodical freshwater inputs. The varying degree of coloration of organic-walled microfossils is interpreted in this study as factor indication of possible different source of their derivation. Dark brown walls of cells assembled in algal coenobia might have sustained previous humification in humid, terrestrial environments, which preceded their river transport into the sea together with nutrients, causing occasional blooms of cyanobacteria in the coastal environment and the final deposition of both groups of organisms in marine deposits.  相似文献   

Permo–Triassic and Liassic Tethyan Oceanic Tracts within the Pontide Belt Along the Southern Margin of Eurasia, Northern Anatolia     

E. SARIFAKIOGLU  Y. DILEK  M. SEVIN  ?. PEHLIVAN  ?. KANDEMIR  A. M?LLER  T. BAYANOVA  I. UYSAL  M. KELES 《《地质学报》英文版》2017,91(Z1):33-34

  相似文献   

风切变对飞行的影响及其预报时效分析     

李秀连  付强  王科  丁叶风 《四川地震》2010,(1)

利用NCEP再分析资料和AMDAR资料,对2008年11月1日首都机场冷锋过境前后风切变现象及其可预报时效进行分析。分析认为:在冷锋过境前后,首都机场存在多种形式的风切变,有高空槽前后的水平风切变、高层和中层急流轴引起的水平风切变、冷锋前逆温层顶上下的水平风切变和地面锋面过境时跑道面上的水平和侧风切变。对各种风切变的可预报时效进行了分析。  相似文献   

北吕宋岛菲律宾活动带蛇绿岩及其上覆浊积岩的放射虫研究新进展     

Keisuke ISHIDA  Shigeyuki SUZUKI  Carla DIMALANTA  Graciano YUMUL JR.  Karlo QUEA?O  Decibel FAUSTINO-ESLAVA  Edanjarlo MARQUEZ  Noelynna RAMOS  Rolando PE?A 《地球学报》2012,33(S1):29-31

The basement of the Philippine Mobile Belt (PMB) is mainly composed of ophiolites that are mostly overlain by Paleogene to Miocene turbidites in central Luzon. To clarify the geological development of the PMB with respect to the initial stage of the arc volcanism (eg. Yumul et al., 2003, 2008; Dimalanta and Yumul, 2003; Suzuki et al., 2011), radiolarian dating was examined in siliceous sediments associated with the ophiolites and turbidites. The samples were collected from sites identified with the Zambales and Montalban ophiolites, basic tuff phyllites in NW Din-galan, and their overlying formations.  相似文献   

西藏努日矽卡岩型铜钨钼矿辉钼矿 Re-Os定年及其地质意义   总被引：5，自引：2，他引：3  

张松  郑远川  黄克贤  李为  孙清钟  李秋耘  付强  梁维 《矿床地质》2012,31(2):337-346

西藏努日层状矽卡岩型铜钨钼矿床是冈底斯东段南缘斑岩-矽卡岩铜多金属成矿带上规模最大的矿床。笔者对采自该矿床的9件不同产状、不同形态含钼矿石中的辉钼矿进行了Re-Os同位素组成分析,获得其模式年龄为23.46~24.77 Ma,等时线年龄为(23.36±0.49) Ma(MSWD=0.60),模式年龄与等时线年龄结果基本一致。由于辉钼矿与黄铜矿、白钨矿呈共生关系,并考虑到该矿区内黄铜矿的年龄〔(23.75±0.18) Ma〕(作者未发表数据),表明努日矽卡岩型铜钨钼矿床的成矿时代为23~24 Ma。结合前人研究资料可见,冈底斯南缘克鲁-冲木达斑岩-矽卡岩铜多金属成矿带从32 Ma至23 Ma发生了强烈的成矿作用。该成矿带的成矿时代明显有别于后碰撞期地壳伸展环境下形成的冈底斯斑岩铜矿带,显示出其为一套独立的成矿事件。该成矿事件可能主要受冈底斯南缘的晚碰撞走滑环境的控制。努日矿床成矿时代的确定及晚碰撞成矿事件的厘定,为今后研究和勘查该成矿带内同类型矿床提供了重要依据。  相似文献   

Petrology and Geochemistry of Post-Collisional Early Miocene Volcanism in the Karacada? Area (Central Anatolia, Turkey)     

Kür?ad ASAN  Hüseyin KURT 《《地质学报》英文版》2011,85(5):1100-1117

Early Miocene (ca.?21–18 Ma) volcanism in the Karacada? area comprises three groups of volcanic rocks: (1) calcalkaline suite (andesitic to rhyolitic lavas and their pyroclastics), (2) mildly-alkaline suite (alkali basalt, hawaiite, mugearite, benmoreite and trachydacite), and (3) a single trachyandesitic flow unit. Field observations, 40Ar/39Ar ages and geochemical data show that there was a progressive temporal transition from group 1 to 3 in a post-collisional tectonic setting. The calcalkaline suite rocks with medium-K in composition resemble those of subduction-related lavas, whereas the mildly-alkaline suite rocks having a sodic tendency (Na2O/K2O=1.5–3.2) resemble those of within-plate lavas. Incompatible element and Sr-Nd isotopic characteristics of the suites suggest that the lithospheric mantle beneath the Karacada? area was heterogeneously enriched by two processes before collision: (1) enrichment by subduction-related processes, which is important in the genesis of the calcalkaline volcanism, (2) enrichment by small degree melts from the astenosphere, which dominates the mildly alkaline volcanism. Perturbation of the enriched lithosphere by either delamination following collision and uplift or removal of the subducted slab following subduction and collision (i.e., slab breakoff) is the likely mechanism for the initiation of the post-collision volcanism.  相似文献   

A New Genus and Species of Damsel-Dragonfly (Odonata: Isophlebioidea: Campterophlebiidae) in the Middle Jurassic of Inner Mongolia, China   总被引：1，自引：0，他引：1  

Julian Fernando PETRULEVI?IUS  HUANG Diying  André NEL 《《地质学报》英文版》2011,85(4):733-738

The campterophlebiid new genus and species Ctenogampsophlebia reni is described from the Middle Jurassic of Inner Mongolia, China. It shows close similarities with the Lower to Middle Jurassic genera Gampsophlebia, and Petrophlebia, with closed and short subdiscoidal cells, confirming the attribution of these two other genera to the Campterophlebiidae.  相似文献