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961.
A FORTRAN Program for tabulating and naming amphibole analyses according to the International Mineralogical Association Scheme 总被引:1,自引:0,他引:1
N. M. S. Rock 《Mineralogy and Petrology》1987,37(1):79-88
Summary Amphibole analyses input to program AMPHTAB (optionally with H2O, F, Cl, minor elements and one or both of Fe2O3, FeO), are output in conventional column tables, with formula units, complete IMA names, and extensive messages indicating the quality of each analysis. AMPHTAB accepts data-files ranging from a single amphibole analysis to (in principle) unlimited batched data-e.g., multiple analyses from each of numerous probe sections. Options are provided to reallocate total Fe in probe data between Fe3 and Fe2, to allow for common analytical problems (e.g., low H2O values), and to enable the number of oxygens in the formula unit to be either preset or assigned automatically. Results for 57 probe analyses are compared with an unpublished BASIC program, which uses a different Fe-reallocation method. Three-quarters of the IMA names resulting from the two programs are essentially identical, despite somewhat different estimated formula units. The remainder are borderline cases, where incidental changes in formula units effect disproportionate differences in name.
Ein FORTRAN-Programm zum tabellieren und benennen von amphibolanalysen entsprechend dem Schema der International Mineralogical Association
Zusammenfassung In das Programm eingegebene Amphibolanalysen (wahlweise mit H2O, F, Cl, Spurenelementen und Fe2O3, und/oder FeO), werden in Form herkömmlicher Spaltentabellen mit den Formeleinheiten, vollständigen IMA-Namen und ausführlichen Bemerkungen bezüglich der Analysenqualität ausgegeben. Das AMPHTAB-Programm verarbeitet Datensätze von einer einzigen Amphibolanalyse bis zu (im Prinzip) unbegrenzten Datenblöcken; z. B. Mehrfachanalysen eines Probenabschnittes von mehreren. Es sind die Möglichkeiten vorgesehen, das Gesamteisen in einer Analyse in die Fe3 und Fe2-Anteile umzurechnen, allgemeine analytische Probleme (z. B. niedrige H2O-Gehalte) zu lösen und die Anzahl der Sauerstoffatome in der Formeleinheit entweder vorzugeben oder automatisch setzen zu lassen. Die Resultate von 57 Mikrosonden-Analysen sind mit einem unveröffentlichten BASICProgramm, das eine andere Methode zur Aufteilung des Fe-Gehaltes benutzt, verglichen worden. Drei Viertel der von den beiden Programmen vorgeschlagenen Mineralnamen sind identisch, trotz einiger unterschiedlich berechneter Formeleinheiten. Die übrigen 25% sind Grenzfälle, bei denen zufällige Veränderungen in den Formeleinheiten unverhältnismäßige Unterschiede in der Benennung bewirkten.相似文献
962.
B. H. Briz-Kishore 《Journal of Earth System Science》1982,91(3):219-234
The use of digital models has increased significantly in recent years with the accessibility of fast computing machines. A
variable dimensioned digital model was constructed for the Shadnagar granite basin using SPECTRUM-7 micro computer to integrate
various hydrogeological characteristics and for their quantitative evaluation. The basin has an areal extent of 437 sq km
and is demarcated with clear water divides in all directions. Transmissivity, recharge and discharge at each cell of the basin
area were estimated by trial and error simulation of the hydrogeological phenomenon under steady state condition. Dynamic
simulation at representative nodes facilitated the estimation of storage coefficient. The capability of the constructed model
was established by the conformance of the simulated hydrographs with the actual behaviour of the ground water system. The
entire studies ammended the earlier arrived estimates of various input/output hydrogeological parameters and evolved a methodology
for efficient processing of aquifer simulation data 相似文献
963.
The second vertical derivatives of gravity and magnetic potential are widely used in geophysical prospecting because of their
better resolution. On the same basis an attempt has been made to obtain the expressions for the second vertical derivative
of the electrical potential and to compute its nature for comparison. Derivative responses over a two-layered earth and also
over an anticlinal structure have been computed and it is shown that the second vertical derivative sounding could be employed
for greater accuracy in finding out the thickness of such beds or the inclination of the sides of the anticline and its depth
when compared with normal resistivity sounding 相似文献
964.
将方差分量估计(VCE)方法应用于ERS-2卫星的精密定轨,用SLR和PRARE资料计算了1998年前3个月的23个长度为5天的弧段(除了调整轨道的时段外,相邻弧段有两天的重叠),从观测值残差分析和重叠弧段比较两个方面,考察VCE方法对定轨计算的影响,并给出了各组观测值的平均验后均方差,对观测值残差的分析表明,使用VCE方法明显地改善了观测值的拟合程度,但从阿卑(Abbey)标准对观测值残差的检验结果来看,使用VCE方法不能消除轨道中由力学模型和几何模型误差引入的系统差,重叠弧段比较的结果表明:(1)使用VCE方法缩小了重叠弧段的平均距离差,并改善了一部分权段明显不合理的偏离,使最后得到的轨道具有更均匀的精度,(2)相比较而言,VCE方法使相邻弧段靠拢的趋势在轨道切向体现得较为明显,由各组观测值的平均验后方差可见,说单个标准点观测值而言,部分SLR台站的观测资料在定轨计算中占有比其他观测资料更重的地位,纵观全文,使用VCE后得到的观测值的平衡验后均方差来确定资料的双重将比使用均方差更为合理。 相似文献
965.
海底X射线荧光探测系统的软件研制 总被引:2,自引:2,他引:0
基于Windows98操作平台,结合软件工程的设计原则和面向对象的程序设计方法,用Visual Basic 6.0开发了海底X射线荧光探测系统软件(EDXRF^MS)。该软件能完成数据处理及运算,主要解决谱数据的采集与测量控制、成图和图形处理、X射线荧光谱分析、干扰因素的校正、仪器标定与含量计算等问题。EDXRF^MS软件与海底X射线荧光探测系统的硬件配合,能够进行海上现场多道数据的实时采集,对于海底矿产资源的开发具有一定的实用价值。 相似文献
966.
本文介绍了GPS、eMODEM、DE-211串口设备服务器等辅助设备在GDQJ-2型固态地震动强度记录仪中的应用,包括各自的功能、作用、实现方法以及和强震仪的接口。 相似文献
967.
Selection of regional historical rainfall time series as input to urban drainage simulations at ungauged locations 总被引:1,自引:0,他引:1
P.S. Mikkelsen H. Madsen K. Arnbjerg-Nielsen D. Rosbjerg P. Harremoës 《Atmospheric Research》2005,77(1-4):4
It has become established practice during the past 20 years to use high-resolution historical rainfall time series as input to hydrological model packages for detailed simulation of urban drainage systems. However, sufficiently long rain series are rarely available from the exact catchment in question and simulations are hence often based on available rain series from other locations. Extreme rainfall properties of importance to the performance of urban storm drainage systems vary significantly even in regions with only minor physiographic differences. Part of this variation can be explained by regional variations of the mean annual rainfall and the remaining statistical residue can be interpreted as statistical uncertainty.In Denmark, more than 75 high-resolution rain gauges are installed across a total area of 43,000 m. About 40 gauges had sufficiently long records to be included in a comprehensive national investigation where newly developed statistical regionalisation procedures were used to model the regional variation of extreme rainfalls. On this basis, a spreadsheet model was made available for estimation of extreme design rainfalls and the associated uncertainty at any location in the country. Statistics were furthermore computed to classify historical rainfall time series according to the developed regional model, and this makes it possible to assess the uncertainty related with using different historical rain series for simulations at ungauged locations.This research indicates that use of historical point rainfall data at ungauged locations introduces a significant uncertainty that is largely overlooked in today's practice. The engineering recommendation is to select historical rain series based on an evaluation of the local physiographic characteristics (e.g., the mean annual rainfall) and a (pre-defined) desired safety level of the simulations. 相似文献
968.
969.
970.
Traveltime measurements from noise correlation: stability and detection of instrumental time-shifts 总被引:1,自引:0,他引:1
We test the feasibility of using Green's functions extracted from records of ambient seismic noise to monitor temporal changes in the Earth crust properties by repeated measurements at regional distances. We use about 11 yr of continuous recordings to extract surface waves between three pairs of stations in California. The correlations are computed in a moving 1-month window and we analyse the temporal evolution of measured interstation traveltimes. The comparison of the arrival times in the positive and negative correlation time of Rayleigh and Love waves allows us to separate time-shifts associated with any form of physical change in the medium, those resulting from clock drift or other instrumental errors, and those due to change in the localization of the noise sources. This separation is based on the principle of time symmetry. When possible, we perform our analysis in two different period bands: 5–10 and 10–20 s. The results indicate that significant instrumental time errors (0.5 s) are present in the data. These time-shifts can be measured and tested by closure relation and finally corrected independently of any velocity model. The traveltime series show a periodic oscillation that we interpret as the signature of the seasonal variation of the region of origin of the seismic noise. Between 1999 and 2005, the final arrival time fluctuations have a variance of the order of 0.01 s. This allows us to measure interstation traveltimes with errors smaller than 0.3 per cent of the interstation traveltime and smaller than 1 per cent of the used wave period. This level of accuracy was not sufficient to detect clear physical variation of crustal velocity during the considered 11 yr between the three stations in California. Such changes may be more easily detectable when considering pairs of stations more closely located to each other and in the vicinity of tectonically active faults or volcanoes. 相似文献