广东近岸海域表层水中^90Sr和^137Cs的分布     

吴世炎  施纯坦 《台湾海峡》1992,11(4):363-367

本文提供了1989～1991年广东近岸表层水中~(90)Sr和~(137)Cs含量的分析结果。在调查海区,~(90)Sr含量为2.31～3.75mBq/L,平均值为3.21±0.45mBq/L。~(137)Cs含量为2.10～4.49mBq/L,平均值为3.47±0.89mBq/L。~(137)Cs/~(90)Sr放射性的比值为0.63～1.69,平均值为1.11±0.35。调查结果表明,近三年来未发现广东近岸海域有明显的人工放射性污染。目前广东近岸海水中的~(90)Sr和~(137)Cs主要仍是以往核试验所产生的放射性落下灰残余。  相似文献   

Beta gyres in global analysis fields     

Sun-Hee KIM  H. Joe KWON  R. L. ELSBERRY 《大气科学进展》2009,26(5):984-994

A three-component decomposition is applied to global analysis data to show the existence of a beta gyre, which causes Tropical Cyclone (TC) to drift from a large-scale environmental steering current. Analyses from the Global Data Assimilation and Prediction System (GDAPS) of the Korea Meteorological Administration (KMA), the Global Forecast System (GFS) of NCEP, and the Navy Operational Global Atmospheric Prediction System (NOGAPS) are used in this study. The structure of the beta gyre obtained in our analyses is in good agreement with the theoretical structure, with a cyclonic circulation to the southwest of the TC center, an anticyclonic circulation to the northeast, and a ventilation flow directed northwestward near the center. The circulation of the beta gyre is strongest at the 850-hPa level where the cyclonically swirling primary circulation is strongest, and decreases with height, in a pyramid shape similar to the primary circulation. The individual structure of the beta gyre is case- and model-dependent. At a certain analysis time, one model may clearly reveal a well-defined beta gyre, but the other models may not. Within one model, the beta gyre may be well defined at some analysis times, but not at other times. The structure of the beta gyre in the analysis field is determined by the nature of the vortex initialization scheme and the model behavior during the 6-h forecast in the operational data assimilation cycle.  相似文献   

PZ-90 GLONASS与ITRF之间转换参数的谱分析     

焦文海  魏子卿  刘光明  何涛 《武汉大学学报(信息科学版)》2003,28(6):740-744

根据BKG中心的转换参数结果，采用FFT方法，计算分析了PZ-90GLONASS与ITRF间转换参数及其周期变化特性，并得出了一些有益的结论。  相似文献   

Shear-wave splitting in a critical crust: III. Preliminary report of multi-variable measurements in active tectonics     

Stuart Crampin  Sebastien Chastin  Yuan Gao   《Journal of Applied Geophysics》2003,54(3-4):265

This is a preliminary report on two sets of recent observations from a region of active tectonics that provide comparatively direct evidence for the critical state of the fluid-saturated microcracked crust. The first data set from crosshole seismics in a controlled source stress-monitoring site (SMS) shows that the crust of the Earth is highly compliant and responds to low-level changes of tectonic stress at substantial distances. The second set of data from earthquake seismograms shows that the seismically active Húsavík–Flatey Fault plane is pervaded by critically high pore-fluid pressures, which cause 90° flips in the polarisations of seismic shear waves. We suggest that both sets of observations confirm previous hypotheses for a compliant crack-critical (CCC) crust. This is a new understanding of low-level pre-fracturing deformation that has fundamental implications for a range of applications in solid earth geophysics. These applications range from monitoring hydrocarbon production with time-lapse seismics to monitoring tectonic stress in in situ rock and stress-forecasting the times and magnitudes of impending large earthquakes.  相似文献   

混合编程在电法资料处理中的应用     

李凤哲  朱庆俊  任妹娟 《物探与化探》2007,31(2):178-180

在电法资料解释系统的开发中，VB和Fortran混合编程具有优势：一方面充分利用了已有的用Fortran编写的成熟的源代码。避免了资源浪费，提高了开发效率；另一方面，克服了Fortran界面不美观、图形处理功能欠缺的缺点。就VB调用Fortran动态链接库进行了详细的介绍，最后辅以实例实现了VB和Fortran的混合编程。  相似文献   

《气象与环境科学》2007年总目次          下载免费PDF全文

杜文娟  李建东 《气象与环境科学》2007,30(4):95-96

阐述了利用VB和Fortran语言混合编程开发气象预报系统的两种方法,一种是利用VB的shell函数调用可执行文件法,另一种是利用VB调用Fortran生成的动态链接库法,并具体介绍了如何通过DLL实现VB 6.0和Fortran的接口,最终实现VB的可视化界面与Fortran强大数值计算能力相结合的新思路.  相似文献   

Visual Fortran 5.0下的重磁数据处理及图像显示     

贺日政  范芸芳 《世界地质》2000,19(2):182-184

重磁数据处理在地球物理中占有很重要的地位.利用Fortran 90语言对现有的Fortran 77程序进行了改写,克服了受内存的限制,并且实现了在Visual Fortran环境下的图形图像显示.  相似文献   

探讨中国区域的WGS-84与PZ-90坐标转换参数     

李程春  姚宜斌  黄承猛  陈鹏  彭文飞 《测绘信息与工程》2011,(5):35-37,40

针对全球范围内WGS-84与PZ-90坐标系转换参数不统一问题,结合中国区域GPS全球IGS永久跟踪站坐标,探讨并研究了适合中国的转换参数,对GPS/GLONASS组合应用有重要意义。  相似文献   

A Franco-American Geographical Encounter     

《The Professional geographer》2013,65(3):367-368

ATLAS?GRAPHICS (Version 3.0).

AutoCAD (Release 9.0 with ADE+1, ADE+2 and ADE+3).

AutoSketch (Speed Enhanced Version 1.02).

NUMERICAL RECIPES FORTRAN. Numerical Recipes Software

SCIPLOT.  相似文献   

Ordovician backarc‐basin metadolerite and metabasalt of the South Kitakami Terrane,Northeast Japan          下载免费PDF全文

Takayuki Uchino  Makoto Kawamura 《Island Arc》2016,25(4):274-286

Basement rocks that occur along the northern margin of the South Kitakami Terrane in Japan consist of Ordovician ultramafic rocks (Hayachine ultramafic complex), gneissose amphibolite (Kuromoriyama amphibolite), and mafic rocks (Kagura igneous rocks, KIR). The KIR are composed of metagabbro, metadolerite, metabasalt, and minor felsic–intermediate dikes. Although the KIR contain green hornblende due to metamorphism of greenschist to epidote–amphibolite facies, they rarely retain primary brown hornblende. Approximately 30% of the metabasalt shows porphyritic textures, with phenocrysts of saussuritized plagioclase and/or altered mafic minerals. The geochemistry of the common metadolerite and metabasalt of the KIR shows a tholeiite trend, a low TiO₂ content, and high Th/Nb and Ti/V ratios. The KIR are therefore indicative of a supra‐subduction zone tectonic setting, which implies a backarc origin (as also indicated by discrimination diagrams). Trace element patterns of the KIR resemble those of the backarc‐basin basalt of the Japan and Yamato basins in the Japan Sea. We propose that the KIR formed during backarc spreading from the Ordovician to Early Silurian. This view is supported by the geochemical data, the tectonic setting of the Hayachine ultramafic rocks, and the provenance of clastics within Silurian sedimentary rocks.  相似文献