Reviews     

Peter R. Odell  Seiya Uyeda  V. P. Zenkovich  C. Koeman  Johannes Ulrich  Maurice K.-Seguin  K. Gerke  U. Vetter  G. T. W. Wittmann  H. J. Habing  J. Gentilli 《GeoJournal》1977,1(1):95-100

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Book reviews     

W. M. Adams  R. Meissner  U. Vetter  G. Kunkel  W. Ritchie  E. Seibold  John E. Bardach  M. J. Orren  M. K. Seguin  G. Müller  Matti Karras 《GeoJournal》1979,3(3):321-328

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High CO2 content of fluid inclusions in gold mineralisations in the Ashanti Belt, Ghana: a new category of ore forming fluids? – a reply     

A. Schmidt Mumm  T. Oberthür  U. Vetter  T. G. Blenkinsop 《Mineralium Deposita》1998,33(3):320-322

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El Niño may affect growth behaviour of Amazonian tress     

Roland E. Vetter  Paulo C. Botosso 《GeoJournal》1989,19(4):419-421

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Rheologic properties of the lithosphere and applications to passive continental margins     

U.R. Vetter  R.O. Meissner 《Tectonophysics》1979,59(1-4)

Thermal and petrologic models of the crust and upper mantle are used for calculating effective viscosities on the basis of constant creep rates. Viscosity—depth models together with pressure—depth models are calculated for continental and oceanic blocks facing each other at continental margins. It is found from these “static models” that the overburden pressure in the lower crust and uppermost mantle causes a stress which is directed from the ocean to the continent. The generally low viscosity of 10²⁰–10²³ poise in this region should permit a creep process which could finally lead to a “silent” subduction. In the upper crust static stresses act in the opposite direction, i.e. from the continent to the ocean, favouring tension which could produce normal faulting in the continent. Differences between observations and the results obtained from the static models are attributed to dynamical forces.  相似文献   

南极大型动物粪土层和蛋卵中有机氯污染物分布特征及生态学意义   总被引：3，自引：0，他引：3  

张海生  王自磐  卢冰  朱纯  武光海  Walter Vetter 《中国科学D辑》2006,36(12):1111-1121

新近从南极菲尔徳斯半岛和阿德雷岛的海鸟和海豹栖息地粪土层中检出持久性有机氯污染物(POPs)总含量范围: 多氯联苯(PCBs)为0.21~3.85 ng/g; 有机氯农药滴滴涕(ΣDDT)为0.09~2.01ng/g; 六六六(ΣHCH)为0.06~0.76 ng/g, 并以七氯、六氯联苯、P, P-DDE和α-HCH化合物为主体; 在贼鸥和巨海燕、企鹅蛋卵中检出POPs含量各为12.5~294.2和2.0~10.2 ng/g (湿重); 积蓄形式以PCB180, PCB153, P, P’-DDE和HCB和P, P’-DDE为主. 研究表明, 栖息地粪土层POPs含量变化与海鸟不同种群食性以及营巢占域的不同而相异; 对不同种类海鸟卵样的POPs数据进行统计分析, 结果显示不同鸟种POPs积累水平的差异取决于不同鸟种的生态习性, 如活动范围、迁徒距离、觅食习性以及巢址选择等, 最重要是海鸟生态食物链中的位置, 其食谱的宽窄, 同样表明海鸟体内POPs积累通过食物链逐渐加强的结果. 其次还对阿德雷岛地区AD1, AD2短柱粪土地层进行²¹⁰Pb测年, 并进行POPs积累率及分子地层学记录的初步研究.  相似文献   

Estimating atmospheric pressure loading regression coefficients from GPS observations     

Klaus Kaniuth  Sandra Vetter 《GPS Solutions》2006,10(2):135-134

The loading exerted by atmospheric pressure on the surface of the Earth causes deformations, mainly in vertical direction. Consequently, these deformations are also subject to pressure variations. At present this effect is only modeled by a few research groups in the post-processing of very long baseline interferometry (VLBI) and global positioning system (GPS) observations. As the displacements may clearly exceed the accuracy goals, we implement vertical pressure loading regression coefficients as a new estimable parameter type in the Bernese GPS software. This development is applied to a network of 60 European permanent GPS stations extending from 35 to 79° northern latitude. The analysis comprises 1,055 days of observations between January 2001 and February 2004. During that period pressure variations as large as 80 hPa occurred at high latitude sites. A least squares solution including all observations and all relevant parameters yields significant regression coefficients for all stations but reveals also some critical issues with regard to the capability of this geodetic approach to verify results based on the geophysical convolution method.An erratum to this article can be found at  相似文献   

Response of the upper ocean to tropical cyclone in the Northwest Pacific observed by gliders during fall 2018     

Zekai Ni  Jiancheng Yu  Xuekun Shang  Wenming Jin  Yeteng Luo  Philip A Vetter  Huichang Jiang  Liu Yu  Sumin Liu  Hongzhou Xu 《海洋学报(英文版)》2021,40(1):103-112

The evolution of thermohaline structure at the upper ocean during three tropical cyclones(TCs) in the Northwest Pacific was studied in this study based on successive observation by two new-style underwater gliders during fall 2018. These remote-controllable gliders with CTD sensor enabled us to explore high frequency responses of temperature, salinity, mixed and barrier layers in the upper ocean to severe TCs in this area. Results showed that three significant cooling-to-warming and stratification destructing-to-reconstructing processes at the mixed layer occurred during the lives of three TCs. The maximal cooling of SST all reached ≥0.5℃ although TCs with different intensities had different minimal distances to the observed area. Under potential impacts of solar radiation, tide and inertial motions, the mixed layer depth possessed significant high-frequency fluctuations during TC periods.In addition, barrier layers appeared and vanished quickly during TCs, accompanied with varied temperature inversion processes.  相似文献   

Modeling the impacts of climate change on nitrogen retention in a 4th order stream     

H. Boyacioglu  T. Vetter  V. Krysanova  M. Rode 《Climatic change》2012,113(3-4):981-999

Climate induced changes of temperature, discharge and nitrogen concentration may change natural denitrification processes in river systems. Until now seasonal variation of N-retention by denitrification under different climate scenarios and the impact of river morphology on denitrification have not been thoroughly investigated. In this study climate scenarios (dry, medium and wet) have been used to characterize changing climatic and flow conditions for the period 2050–2054 in the 4th order stream Weiße Elster, Germany. Present and future periods of nitrogen turnover were simulated with the WASP5 river water quality model. Results revealed that, for a dry climate scenario, the mean denitrification rate was 71% higher in summer (low flow period between 2050 and 2054) and 51% higher in winter (high flow period) compared to the reference period. For the medium and wet climate scenarios, denitrification was slightly higher in summer (3% and 4%) and lower in winter (9% and 3% for medium and wet scenarios, respectively). Additionally, the variability of denitrification rates was higher in summer compared to winter conditions. For a natural river section, denitrification was a factor of 1.22 higher than for a canalized river reach. Besides, weirs along the river decrease the denitrification rate by 16% in July for dry scenario conditions. In the 42 km study reach, N-retention through denitrification amounted to 5.1% of the upper boundary N load during summer low flow conditions in the reference period. For the future dry climate scenario this value increased up to 10.2% and for the medium climate scenario up to 5.4%. In our case study the investigated climate scenarios showed that future discharge changes may have a larger impact on denitrification rates than future temperature changes. Overall results of the study revealed the significance of climate change in regulating the magnitude, seasonal pattern and variability of nitrogen retention. The results provide guidance for managing nitrogen related environmental problems for present and future climate conditions.  相似文献   

Seismic hazard evaluation for dams in northern Colorado, U.S.A.     

Ute R. Vetter  Jon P. Ake  Roland C. Laforge 《Natural Hazards》1996,14(2-3):227-240

A seismic hazard evaluation for three dams in the Rocky Mountains of northern Colorado is based on a study of the historical seismicity. To model earthquake occurrence as a random process utilizing a maximum likelihood method, the catalog must exhibit random space-time characteristics. This was achieved using a declustering procedure and correction for completeness of recording. On the basis of the resulting a- and b-values, probabilistic epicentral distances for a 2 × 10^–5 annual probability were calculated. For a random earthquake of magnitude M _L 6.0–6.5, this distance is 15 km. Suggested ground motion parameters were estimated using a probabilistic seismic hazard analysis. Critical peak horizontal accelerations at the dams are 0.22g if median values are assumed and 0.39g if variable attenuation and seismicity rates are taken into account. For structural analysis of the dams, synthetic acceleration time series were calculated to match the empirical response spectra. In addition, existing horizontal strong motion records from two Mammoth Lakes, California earthquakes were selected and scaled to fit the target horizontal acceleration response spectra.  相似文献