福州市地表干湿分布特征及其与农业干旱的关系   总被引：5，自引：0，他引：5  

马治国  陈惠 《气象科技》2008,36(1):82-86

利用常规资料、NCEP再分析等资料,对0604号强热带风暴碧利斯造成华南持续特强暴雨的特点及成因进行了综合分析.结果表明:虽然碧利斯最强时只达强热带风暴强度,但在其登陆后与强西南季风持续地相互作用,在台风南侧形成强盛的水汽输送和辐合上升机制,且辐合上升运动、高层辐散及水汽辐合中心强度异常强盛,为近年台风少有,且大暴雨区与强水汽辐合上升中心十分吻合;华南持续5天强暴雨与台风低压与西南季风持续结合及副高断裂有密切关系;碧利斯对促使西南季风明显增幅北抬也起了重要作用.  相似文献   

五台山站历史气候资料的均一性分析   总被引：2，自引：0，他引：2  

高晓容  李庆祥  董文杰 《气象科技》2008,36(1):112-118

介绍了新一代天气雷达实时监测系统的结构模式和功能,通过TCP/IP通信协议的论述、天气雷达信息量和占用信道带宽的估算,证明基于宽带网络系统通信设计的可行性.同时详细分析了CINRAD/SA天气雷达实时监测信息的结构和存放特点,系统地描述天气雷达监测信息获取、传送和入库的方法,并重点介绍如何编制传输和入库软件,利用TCP/IP两种基本协议(TCP和UDP)以及ADO数据库编程技术,在现有的宽带网络基础上,对天气雷达运行状况实现远程实时监测.  相似文献   

Follow‐up observations of Comet 17P/Holmes after its extreme outburst in brightness end of October 2007     

M. Mugrauer  M.M. Hohle  C. Ginski  M. Vanko  F. Freistetter 《Astronomische Nachrichten》2009,330(5):425-429

We present follow‐up observations of comet 17/P Holmes after its extreme outburst in brightness, which occurred end of October 2007. We obtained 58 V‐band images of the comet between October 2007 and February 2008, using the Cassegrain‐Teleskop‐Kamera (CTK) at the University Observatory Jena. We present precise astrometry of the comet, which yields its most recent Keplerian orbital elements. Furthermore, we show that the comet's coma expands quite linearly with a velocity of about 1650 km/s between October and December 2007. The photometric monitoring of comet 17/P Holmes shows that its photometric activity level decreased by about 5.9 mag within 105 days after its outburst (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

Short-period Jupiter family comets after Stardust     

M.J. Burchell  A.T. Kearsley 《Planetary and Space Science》2009,57(10):1146-3513

The NASA Stardust mission has provided for laboratory study an extensive data set of cometary dust of known provenance (from comet 81P/Wild 2) yielding detailed insights into the composition of the comet. Combined with the results of data from other missions to short-period Jupiter family comets (JFC), this has greatly deepened the understanding of such objects. If depressions on the surface of comet 81P/Wild 2 are all taken as evidence of impact cratering, their number suggests a long occupancy in the outer region of the Solar System. The dust from comet 81P/Wild 2 has been shown to be heavily deficient in pre-Solar grains and rich in materials formed at high temperatures in the inner Solar System. Although it is too early to know if this is typical of JFC, it does argue for rapid and thorough mixing of materials in the disk on timescales related to comet formation, and may also suggest outward migration of small icy bodies after their formation. Thus, instead of providing mainly new knowledge of the pre-Solar materials expected to be rich in comets, Stardust and comet 81P/Wild 2 have instead focussed attention on large-scale transport processes during the critical period when cometary parent bodies were forming in the early Solar System.  相似文献   

浅谈测绘的社会作用   总被引：4，自引：2，他引：2  

石如文 《测绘与空间地理信息》2005,28(2):40-41

人类社会已进入了崭新的信息化时代,测绘在经济建设和社会发展中起着非常重要的作用,测绘行业要努力为社会主义现代化建设提供测绘保障。  相似文献   

城市测绘院办公自动化系统的设计     

杨文森  罗年学  秦政国  任献军 《地理空间信息》2005,3(3):25-26,38

介绍了基于NET Framework的城市测绘院办公自动化系统的设计及开发方案。  相似文献   

四川省九龙县黑牛洞富铜矿矿床黑云母40Ar-39Ar测年及其地质意义   总被引：6，自引：1，他引：5  

马国桃 《地质学报》2009,83(5):671-679

四川省九龙县黑牛洞铜矿床为近期新发现的一个规模在中型以上,产于江浪变质核杂岩中的富铜矿床。本文测试了黑牛洞铜矿床中与成矿密切相关的黑云母的40Ar/39Ar年龄为136.43±0.77 Ma,说明黑牛洞矿床形成于燕山中期。结合矿区附近李伍富铜床矿床地质特征及成矿年龄,表明黑牛洞铜矿床与李伍铜矿床为同一时期形成的矿床,两者成矿与松潘－甘孜造山带大规模岩浆热事件有关,这对于重新认识李伍铜矿床外围找矿潜力和进一步指导找矿工作具有重要意义。  相似文献   

川西北花岗岩的冷却过程及其对区域成矿的制约   总被引：4，自引：1，他引：3  

李建康 《地质学报》2009,83(8):1141-1149

川西北地区位于松潘-甘孜造山带北部,产出众多的中生代花岗岩和卡林型金矿,金成矿作用与区域构造运动和岩浆活动有密切的内在联系。本文拟从花岗岩的角度分析这种内在联系,故测定了川西北的羊拱海黑云母二长花岗岩、达盖寨黑云母二长花岗岩和可尔因二云母二长花岗岩的黑云母或白云母Ar-Ar年龄,分别得到坪年龄158.7±1.4Ma、185.2±1.4Ma、和157.6±1.2Ma,并参考积累的川西北花岗岩体的年代学数据,绘制了造山带北部、中部、东缘中部几个主要花岗岩体的冷却轨迹。不同构造位置花岗岩体的冷却轨迹表明,从造山带北部到造山带东缘中部,各花岗岩体的侵位年龄依次变新,冷却速率依次变缓,在区域构造运动相对较弱期间,各花岗岩的冷却速率明显降低。由以上特征,本文推断在中生代陆内造山过程中,构造应力自松潘-甘孜造山带北部向造山带东缘中部传递,各区域先后由造山相对活跃期进入造山相对宁静期。在造山宁静期,构造运动较弱,花岗岩体缓慢冷却,地壳较长时间保持低温状态,利于金的成矿作用。因而,川西北的金矿主要形成于区域花岗岩的缓慢冷却阶段,这可能是金矿与花岗岩时空耦合的原因之一。  相似文献   

Metamorphic garnet pyroxenite from the 540-600 m main borehole of the Chinese Continental Scientific Drilling (CCSD) project   总被引：1，自引：0，他引：1  

Lingsen Zeng  Fenghua Liang  Fulai Liu 《Tectonophysics》2009,475(2):396-412

Compared to other mafic and ultramafic rocks from the CCSD main borehole as well as from the outcrops, rocks from the 540-600 m section is extraordinary in terms of its geophysical as well as geochemical properties. It consists of > 70% hematite-ilmenite garnet pyroxenite (HI-GPX) and < 30% intercalated rutile garnet pyroxenite (R-GPX). Whole-rock geochemical data show that HI-GPXs have: (1) relatively high V with an average of 606 ppm, but lower Nb and Ta; (2) highest TFeO, Fe₂O₃/FeO ratio, and highly variable but strong positive Eu anomalies with Eu/Eu? up to 2.9; (3) anomalously high V/Sc ratios ranging from 8.39 to 43.23, average 15.03; and (4) high amounts of hematite-ilmenite solid solutions with a very fine intergrowth structure down to nanometer scale. V/Sc ratios in the CCSD garnet pyroxenites are correlated negatively with MgO, but positively with Fe₂O₃/FeO ratios. Both suites of pyroxenites have similar rare earth elements and high field strength elements geochemistry. These features demonstrate that these pyroxenites were formed from metamorphism of high-Fe and/or -Ti gabbroic cumulates. This can account not only for low high field strength elements (HFSE) and rare earth elements (REE) but also low Nb/Ta and Zr/Hf ratios in these rocks. Seemingly negative correlation between Nb/Ta and Zr/Hf in the CCSD metabasites, not significantly affected by UHP metamorphism, is also consistent with the silicate differentiation trend in a basaltic magma chamber.  相似文献   

Origin of fault domains and fault-domain boundaries (transfer zones and accommodation zones) in extensional provinces: Result of random nucleation and self-organized fault growth     

Roy W. Schlische  Martha Oliver Withjack   《Journal of Structural Geology》2009,31(9):910

In many extensional provinces, large normal faults dip in the same direction forming fault domains. Features variously named transfer faults, transfer zones, and accommodation zones (hereafter non-genetically referred to as fault-domain boundaries) separate adjacent fault domains. Experimental modeling of distributed extension provides insights on the origin, geometry, and evolution of these fault domains and fault-domain boundaries. In our scaled models, a homogeneous layer of wet clay or dry sand overlies a latex sheet that is stretched orthogonally or obliquely between two rigid sheets. Fault domains and fault-domain boundaries develop in all models in both map view and cross-section. The number, size, and arrangement of fault domains as well as the number and orientation of fault-domain boundaries are variable, even for models with identical boundary conditions. The fault-domain boundaries in our models differ profoundly from those in many published conceptual models of transfer/accommodation zones. In our models, fault-domain boundaries are broad zones of deformation (not discrete strike-slip or oblique-slip faults), their orientations are not systematically related to the extension direction, and they can form spontaneously without any prescribed pre-existing zones of weakness. We propose that fault domains develop because early-formed faults perturb the stress field, causing new nearby faults to dip in the same direction (self-organized growth). As extension continues, faults from adjacent fault domains propagate toward each another. Because opposite-dipping faults interfere with one another in the zone of overlap, the faults stop propagating. In this case, the geometry of the domain boundaries depends on the spatial arrangement of the earliest formed faults, a result of the random distribution of the largest flaws at which the faults nucleate.  相似文献