The devastating MS8.0 Wenchuan earthquake ruptured two large parallel thrust faults along the middle segment of the Longmenshan thrust belt. Preseismic and postseismic leveling data indicated the hanging wall of the YingxiuBeichuan-Nanba thrust fault mainly presented coseismic uplift with respect to the reference point at Pingwu county town, and the observed maximum uplift of 4.7 m is located at Beichuan county (Qushan town) which is about 100 m west of the fault scarp. The foot wall of the Yingxiu-Beichuan-Nanba thrust fault mainly showed subsidence with maximum subsidence of 0.6 m near the rupture. By employing a listric dislocation model, we found that the fault geometry model of exponential dip angle δ= 88°?×1-exp(-9/h) with depth of 18 km and uniform thrust-slip of 5.6 m could fit the observed coseismic vertical deformation very well, which verifies the listric thrust model of the Longmenshan orogenic zone.
The study on the coupling relationship and hydrology mechanism between ecosystem and hydrological process in a basin has recently become the international research frontier in hydrology.Runoff separation is still an important subject and possibly cutting edge process in hydrology.This paper summarizes the progress of national and international research,and comments on the advantages and disadvantages of recent,diverse base flow separation methods.This paper also presents research on hydrological process and eco-hydrological function in different landscape zones,combining isotopic technology with hydrochemical methods.Based on the runoff separation of different water bodies,this paper probes into the coupling relationship and hydrology mechanism between ecosystem pattern and eco-hydrological process,and makes analysis on water conservation,regulation and storage mechanism,and eco-hydrological function in different landscape zones.This report also examines future trends in research on hydrological process and eco-hydrological function in mountainous areas. 相似文献
In this paper, the mobile strong ground motion observation for the destructive earthquake is introduced.Considering the characteristics and its spatial distributions of aftershock, 59 strong ground motion instruments were installed along the Longmenshan fault area, and more than 2 000 records have been accumulated.It shows that it is necessary to per-form the mobile strong ground motion observation after the destructive earthquake, and the precious collected data could be applied for further research. 相似文献
Explicit algebraic equations are derived to determine approximate maximum pumping rates or minimum injection rates to limit sea water intrusion to a prespecified distance from the coastline. The equations are based on Strack's (1976) single-potential solution. The maximum pumping rates and minimum injection rates applied at wells with uniform spacing to control the inland movement of the fresh water-salt water interface in a coastal aquifer could be calculated from Strack's (1976) solution without the need of a numerical optimization algorithm. When wells are distributed in a simple fashion, the maximum intrusion location can be identified precisely for pumping cases and approximately for injection cases. For pumping cases, critical points are the limit of allowable salt water intrusion, whereas no such limit exists for injection cases. Once an application site is identified, a series of design curves for pumping and injection rates can be developed for arbitrary intrusion limits. When a user is interested only in the largest pumping rates associated with critical points, one design curve can yield complete information. 相似文献