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Deep-crustal earthquakes in the southern Baltic Shield 总被引:1,自引:0,他引:1
Ronald Arvidsson Rutger Wahlström Ota Kulhánek 《Geophysical Journal International》1992,108(3):767-777
364.
Yuri V. Lyubitsky 《Natural Hazards》1995,11(2):99-110
All the available historic records of sea level and appropriate weather charts have been used to study storm surges in the northern part of the Sea of Japan. The generation of surges in this area was investigated by means of a two-dimensional numerical model. Computed sea levels were compared with hourly observed residual sea levels in De-Kastri. The agreement between computed and observed storm surges is quite satisfactory. The relative importance of various meteorological parameters and bottom topography in formation of the strong storm surge on 20–21 September 1975 was studied numerically. 相似文献
365.
本文将银山成矿体系为富含H2S,CO2的NaCl体系,对Cu,Pb,Zn,Ag和Au等金属元素在该体系降温过程中的地球化学行为和银山矿床的成矿过程进行计算机数字模拟,并与沸腾降温体系进行对比,证明了成矿体系地球化学演化对金属元素的迁移与沉淀具有得要影响。成矿硫体地球化学模拟在矿床成因,深部成矿预测和区域成矿规律研究中具有重要意义。 相似文献
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367.
Parabolic density function in sedimentary basin modelling 总被引:1,自引:0,他引:1
For modelling sedimentary basins of large thickness from their gravity anomalies, the concept of parabolic density function which explains the variation of true density contrast of the sediments with depth in such basins is introduced inBott's (1960) procedure. The analytical expression the gravity anomaly of a two-dimensional vertical prism with parabolic density contrast needed to estimate the gravity effect of the basin in modelling procedure is derived in a closed form. Two profiles of gravity anomalies, one across San Jacinto Graben, California and the other across Tucson basin, Arizona where the density of sediments is found to vary with depth are interpreted. 相似文献
368.
ABSTRACTFlood risk management strongly relies on inundation models for river basin zoning in flood-prone and risk-free areas. Floodplain zoning is significantly affected by the diverse and concurrent uncertainties that characterize the modelling chain used for producing inundation maps. In order to quantify the relative impact of the uncertainties linked to a lumped hydrological (rainfall–runoff) model and a FLO-2D hydraulic model, a Monte Carlo procedure is proposed in this work. The hydrological uncertainty is associated with the design rainfall estimation method, while the hydraulic model uncertainty is associated with roughness parameterization. This uncertainty analysis is tested on the case study of the Marta coastal catchment in Italy, by comparing the different frequency, extent and depth of inundation simulations associated with varying rainfall forcing and/or hydraulic model roughness realizations. The results suggest a significant predominance of the hydrological uncertainty with respect to the hydraulic one on the overall uncertainty associated with the simulated inundation maps. 相似文献
369.
ABSTRACT In this study, the distributed catchment-scale model, DiCaSM, was applied on five catchments across the UK. Given its importance, river flow was selected to study the uncertainty in streamflow prediction using the Generalized Likelihood Uncertainty Estimation (GLUE) methodology at different timescales (daily, monthly, seasonal and annual). The uncertainty analysis showed that the observed river flows were within the predicted bounds/envelope of 5% and 95% percentiles. These predicted river flow bounds contained most of the observed river flows, as expressed by the high containment ratio, CR. In addition to CR, other uncertainty indices – bandwidth B, relative bandwidth RB, degrees of asymmetry S and T, deviation amplitude D, relative deviation amplitude RD and the R factor – also indicated that the predicted river flows have acceptable uncertainty levels. The results show lower uncertainty in predicted river flows when increasing the timescale from daily to monthly to seasonal, with the lowest uncertainty associated with annual flows. 相似文献
370.
Isaac Larbi Emmanuel Obuobie Anne Verhoef Stefan Julich Karl-Henz Feger Aymar Yaovi Bossa 《水文科学杂志》2020,65(13):2196-2209
ABSTRACT The need for a detailed investigation of the Vea catchment water balance components cannot be overemphasized due to its accelerated land-cover dynamics and the associated impacts on the hydrological processes. This study assessed the possible consequences of land-use change scenarios (i.e. business as usual, BAU, and afforestation for the year 2025) compared to the 2016 baseline on the Vea catchment’s water balance components using the Soil and Water Assessment Tool (SWAT) model. The data used include daily climate and discharge, soil and land use/land cover maps. The results indicate that the mean annual water yield may increase by 9.1% under the BAU scenario but decrease by 2.7% under the afforestation scenario; actual evapotranspiration would decrease under BAU but increase under afforestation; and groundwater recharge may increase under both scenarios but would be more pronounced under the afforestation scenario. These outcomes highlight the significance of land-cover dynamics in water resource management and planning at the catchment. 相似文献