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331.
本文详细介绍了位场局部异常人机交互解释系统软件设计的细节和技巧。本系统的软件设计采用了受到广泛欢迎的菜单驱动的用户界面程序设计风格,力图模仿Turbo系列软件的菜单样式和功能,为使用本软件系统尽可能提供方便。 相似文献
332.
利用空间均匀网格对中国夏季降水异常区域特性的初步分析 总被引:24,自引:1,他引:24
用方差极大正交转动EOF(Varimax EOF)及点相关图法分析了夏季总降水(6、7、8月降水之和)及逐月降水的区域特性。使用的资料为全国范围47个5°×5°经纬度网格上的降水资料,分析时段为1959—1994年。分析结果表明,由于采用了空间均匀的格同资料,本分析除进一步证实了中国东部地区降水异常的区域特性外,也揭示了西部地区降水异常的区域特性及沿长江流域东西方向上降水异常的相互关系。夏季总降水异常最显著的区域特性是江淮流域与河套及华南反相关。另外沿长江流域,四川盆地的降水异常与青藏高原东部及江淮流域的降水异常也存在着反相关联系。西部地区的区域特性为青藏高原中东部南北两侧为负相关,并且青藏高原中东部南侧的降水异常与华北东部及东北南部为正相关。上述的空间模都有准2—3a及10a左右的周期。逐月降水的分析表明,6月份,江淮流域、华北东部及东北大部分地区为正相关。7月,河套地区与江淮流域的降水异常呈现一定的负相关联系,8月份降水异常的区域特性与夏季总降水异常的区域特性极其一致。 相似文献
333.
A STUDY OF CLIMATOLOGICAL ASPECTS OF FLOW FIELD AND HEAT EXCHANGE ON TROPICAL PACIFIC SURFACE IN THE EL NINO AND LA NINA EVENTS
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In this paper, based on the 2°× 2° grid data COADS from 1950—1987 the flow field and heatexchange anomalies on the tropical (11°S—11°N, 120°E—80°W) Pacific surface (TPS) are studiedin El Nino and La Nina events. During E1 Nino, the zonal pressure gradient and the trade windsdecrease on the TPS, the tropical convergence strengthens on the TPS, especially on the centralTPS, the sensible and latent heat exchanges increase, the net longwave radiation and incident solarradiation decrease and the net gain (loss) of heat reduces (increases) on the central and easternTPS. During La Nina the results turn out the contrary. Finally, two feedback mechanisms whichinclude the dynamic, thermal and hydrological processes during E1 Nino and La Nina are summa-rized and a conceptive model for El Nino-La Nina cycle is given. 相似文献
334.
335.
Procedures to calculate mean sea surface heights and gravity anomalies from altimeter-derived sea surface heights and along-track
sea surface slopes using the least-squares collocation procedure are derived. The slope data is used when repeat track averaging
is not possible to reduce ocean variability effects. Tests were carried out using Topex, Geosat, ERS-1 [35-day and 168-day
(2 cycle)] data. Calculations of gravity anomalies in the Gulf Stream region were made using the sea surface height and slope
data. Tests were also made correcting the sea surface heights for dynamic ocean topography calculated from a degree 360 expansion
of data from the POCM-4B global ocean circulation model. Comparisons of the anomaly predictions were carried out with ship
data using anomalies calculated for this paper as well as others.
Received: 19 August 1996 / Accepted: 14 April 1997 相似文献
336.
本文提出了三度体重磁异常的人机联作校正-迭代反演方法。该方法用二度半组合多边形棱柱体来逼近三度体,从而把三度体重磁异常反演问题转化为二度半体的反演问题;为了消除组合体迭加场的影响,该方法采用了一种校正-迭代技术。理论模型反演计算表明,该方法实际可行。 相似文献
337.
关于铀、金矿源层(岩)与地球化学负异常的讨论 总被引:1,自引:0,他引:1
借鉴成矿物质取源于矿源层(岩)的思想,作者提出了地球化学场成矿元素的正、负异常相匹配的地区是最有利于成矿的远景区。 相似文献
338.
M. H. Shapiro A. Rice M. H. Mendenhall J. D. Melvin T. A. Tombrello 《Pure and Applied Geophysics》1984,122(2-4):309-326
Four techniques (pattern recognition, Fourier transformation, cross-correlation, and multiple linear regression) have been used to recognize nontectonic environmental factors affecting groundwater radon data collected by the Caltech automated geochemical network. Several factors, including air temperature, rainfall, water level, carbon dioxide concentration in the water, and barometric pressure, were found to correlate with radon level at some stations in the network. For example, approximately 60% of the variance in radon signal at one site studied (Pacoima) could be accounted for by nontectonic influences. However, it was not possible to correlate all the observed changes in radon concentration with nontectonic environmental variables. Some of the observed radon anomalies did appear to be related to either regional changes in tectonic strain or some individual earthquakes. A model is developed to account for spike-like increases in radon caused by carbon dioxide emission. 相似文献
339.
The Narmada-Son lineament (NSL) forms a major tectonic feature on the Indian subcontinent. The importance of this lineament lies in its evolution as well as its tectonic history. The lineament seems to have been active since Precambrian times. In order to understand the history of its evolution, it is necessary to know what igenous activity has been taking place along this lineament, and how the Deccan trap volcanics, which cover large areas along this lineament, have erupted.For the study of this problem an analysis of the aeromagnetic anomaly map lying between 76°15 to 77°30E and 21°45 to 22°50N has been carried out. Four different profiles (B
1
B
1,B
2
B
2,B
3
B
3 andB
4
B
4) have been drawn in N-S direction over this area and interpreted in terms of the intrusive bodies present within or below the surface of Deccan trap exposures. Inversion and forward modelling techniques have been adopted for interpretation purposes. An analysis of frequency spectra along the profiles has also been carried out to estimate the average depth of the different magnetic bodies. These results have been correlated with the available geological information. It has been found that most of the small wavelength anomalies are caused by dyke-like bodies within or below the Deccan trap at a depth of less than 0.5 km. 相似文献
340.