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151.
152.
SERPENTINIZATION OF THE MANTLE WEDGE BY FLUIDS DERIVED FROM CONTINENTAL CRUSTAL MATERIAL: EVIDENCE FROM Nd ISOTOPIC SIGNATURES OF SERPENTINITES (TSO MORARI DOME,ELADAKH)1 deSigoyerJ ,GuillotS .Glaucophane bearingeclogitesintheTsoMoraridome (easternLadakh ,NWHimalaya) [J] .Euro peanJournalofMineralogy ,1997,9:10 73~ 10 83.
2 deSigoyerJ,ChavagnacV ,VillaIM ,etal.DatingtheIndiancontinentalsubductionandcollisionalthicke… 相似文献
153.
Kewal K.Sharma 《地学前缘》2000,(Z1)
LATE PLEISTOCENE—HOLOCENE RAPID UPLIFT AND EROSION IN TIBET: CONSTRAINTS FROM COSMOGENIC EXPOSURE AGE DATA1 CopelandP ,HarrisonTM ,KiddWSF ,etal.RapidearlyMioceneaccelerationofupliftintheGangdeseBelt,Xizang(southernTibet) ,anditsbearingonaccommodationmechanismsoftheIndian Asiacollision[J].EarthPlanetSciLett,1987,86 :2 40~ 2 5 2 .
2 FieldingEJ .Tibetupliftanderosion[J].Tectonophysics,1994,2 6 0 :5 5~ 84.
3 HarrisonTM ,CopelandP ,Ki… 相似文献
154.
A large-scale, manipulative experiment was conducted to examine the extent and rate of recovery of meadows of the temperate Australian seagrass, Amphibolis griffithii to different light-reduction scenarios typical of dredging operations, and to identify potential indicators of recovery from light reduction stress. Shade cloth was used to mimic different intensities, durations and start times of light reduction, and then was removed to assess the recovery. The meadow could recover from 3 months of light stress (5-18% ambient) following 10 months re-exposure to ambient light, even when up to 72% of leaf biomass was lost, much faster recovery rates than has previously been observed for large seagrasses. However, when the meadow had been shaded for 6-9 months and more than 82% of leaf biomass was lost, no recovery was detected up to 23 months after the light stress had ceased, consistent with other studies. Five potential indicators of recovery were recommended. 相似文献
155.
多次波一直是影响地震处理与解释的主要因素之一.本文基于表层相关多次波衰减(Surface Related Multiple Elimination,SRME)理论,对其进行一定的改造,使其可以预测出海底电缆(Ocean Bottom Cable,OBC)数据中所有与表层相关的多次波,而后将预测出的多次波自适应减去.本文对OBC波场,OBC多次波的压制方法给出了介绍,对SRME方法压制OBC多次波理论给出了详尽的阐述.利用SRME理论预测OBC多次波完全数据驱动,不需要地下介质的任何信息,理论数据验证了方法的有效性. 相似文献
156.
M.O.Andreae D.Rosenfeld P.Artaxo A.A.Costa G.P.Frank K.M.Longo M.A.F.Silva-Dias 康凤琴 《干旱气象》2004,22(2):82-88
人们观测到亚马逊森林大火的浓烟减小了云滴的大小,使降水产生延迟。因为清洁云在云底以上1.5km处就可以产生降水,而被污染的云中这个高度要抬升到5km以上.在火成云中就要到7km以上了。云中低层被抑止的降雨和气溶胶沉降使得水份和烟尘向高层输送,高层的云就像能卸下很多污染物的‘烟’。在抬高了的降雨启动高度上,由于相变触发的上升气流导致强的雷雨、大雹以及其他类似的云体突破云顶进入平流层,在平流层沉降的污染物和水汽的辐射效应对气候系统有深刻的影响。大气中激发的风暴在更高层释放出潜热,这就从本质上影响了区域和全球的环流系统。这些过程共同影响了水份循环、大气中污染物的分布以及大气环流的动力学特征。 相似文献
157.
The long-term variability of the Indian summer monsoon rain-fall and related regional and global param-eters are studied. The cubic spline is used as a digital filter to smooth the high frequency signals in the time series of the various parameters. The length of the data series varies from 95 to 115 years during the period 1871-1985. The parameters studied within the monsoon system are: (a) monsoon rainfall of the country as a whole; (b) number of break-monsoon days during July and August; (c) number of storms/ depressions in Bay of Bengal and Arabian Sea during summer monsoon season; and (d) dates of onset of summer monsoon over South Kerala Coast. The parameters studied outside the monsoon system are: (a) the Wright’s Southern Oscillation Index (June-July-August); (b) the January mean Northern Hemi-spheric surface air temperature anomaly; and (c) the East-equatorial Pacific sea surface temperature anomaly.In order to examine the variability under various degrees of the smoothing, the series are filtered with splines of 50% variance reduction frequency of one cycle per 10, 20 and 30 years. It is observed that the smoothed time series of the parameters within the monsoon system comprise a common slowly varying com-ponent in an episodic manner distinctly showing the excess and deficient rainfall epochs. The change of intercorrelations between the time series with increasing degree of smoothing throws some light on the time scales of the dominant interactions. The relation between Southern Oscillation and East equatorial Pacific sea surface temperature and the Indian summer monsoon seems to be dominant on the interannual scale. The low frequency variations are found to have significantly contributed to the instability of the correlations of monsoon rainfall with parameters outside the monsoon system. 相似文献
158.
NO<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript> change over China and its influences 总被引:2,自引:0,他引:2
A 3-D chemical transport model (OSLO CTM2) is used to investigate the impact of the increase of NOx emission over China. The model is capable to reproduce basically the seasonal variation of surface NOx and ozone over eastern China. NOx emission data and observations reveal that NOx over eastern China increases quite quickly with the economic development of China. Model results indicate that NOx concentration over eastern China increasingly rises with the increase of NOx emission over China, and accelerates to increase in winter. When the NOx emission increases from 1995 to its double, the ratio of NO2/NOx abruptly drops in winter over northern China. Ozone at the surface decreases in winter with the continual enhancement of the NOx level over eastern China, but increases over southern China in summertime. It is noticeable that peak ozone over northern China increases in summer although mean ozone changes little. In summer, ozone increases in the free troposphere dominantly below 500 hPa.Moreover, the increases of total ozone over eastern China are proportional to the increases of NOx emission.In a word, the model results suggest that the relationship between NOx and ozone at the surface would change with NOx increase. 相似文献
159.
L. A. A. N. Wickramasinghe 王卫强 刘雨 M. K. Abeyratne W. C. Hemamali K. B. S. S. J. Ekanayake 《南京气象学院学报》2020,12(4):472-482
利用20年(1992-2012年)的ECCO2模式模拟数据,主要研究了东印度洋(EIO)水体输运的季节变化.在EIO选取3个断面,分别为赤道、80°E和6°N.研究结果表明,跨赤道和80°E的季节输运主体部分大致相补偿.跨赤道的大部分水体输运局限在上层100 m,80°E的水体输运具有复杂结构,与显著的季风流、Wyrtki Jets(WJs)、赤道潜流(EUC)等有关.6°N上层水体净输运较小,但存在较强的边界流和相对较弱的内区流.纬向流的显著变化发生在80°E.在季风盛行季节,由于WJs减弱,赤道附近的水体输运以西向的梯度流为主,上层100 m的其余区域则主要受季风流控制.同样,由于EUC减弱,西向的梯度流与次表层东向的EUC之间也存在转换.在季风转换季节,季风流减弱,WJs与EUC分别在上层100 m和次表层占主导地位.此外,本研究还讨论了与季风流、WJs和EUC相关的盐水和暖水交换,有助于了解研究区域内温度和盐度的水平和垂直结构. 相似文献
160.
E.K.KRISHNA KUMAR S.ABHILASH SANKAR SYAM P.VIJAYKUMAR K.R.SANTOSH A.V.SREENATH 《大气科学进展》2023,40(4):697-710
The inverse relationship between the warm phase of the El Ni?o Southern Oscillation(ENSO) and the Indian Summer Monsoon Rainfall(ISMR) is well established. Yet, some El Ni?o events that occur in the early months of the year(boreal spring) transform into a neutral phase before the start of summer, whereas others begin in the boreal summer and persist in a positive phase throughout the summer monsoon season. This study investigates the distinct influences of an exhausted spring El Ni?o(springtime)... 相似文献