Coseismic deposits are easily transported outside of valleys, thereby inflicting damage through debris flows or aggregating and elevating riverbeds in the fluvial network. The evolution of coseismic deposits is crucial for predicting the sediment transport capacity and export time for managing postseismic geohazards; however, this evolution remains unclear. In this study, the spatiotemporal evolution of coseismic deposits due to rainfall is quantified at the valley scale to further obtain the sediment transport capacity. The results show that the relative average thickness predominantly controls the evolution pattern of the coseismic deposits. The sediment transport capacity, which is primarily influenced by rainfall conditions and topography, can be drastically increased by dam breaching and channel narrowing. Moreover, the computed export time, which significantly varies with the spatiotemporal distribution of deposits and the local climate, ranges from 2 to 80 years in the areas affected by the Wenchuan earthquake. This study contributes to providing scientific guidelines for efficiently managing postseismic geohazards and planning for disaster mitigation.
Natural Hazards - Tsunamis occur not only in marine settings but also in lacustrine environments. Most of the lacustrine tsunamis are caused by seismically- or aseismically-triggered mass... 相似文献
<正>This study used trace elements in olivine as a new petrogenetic indicator to further constrain the petrogenesis of potassic basalts from the Erkeshan-Wudalianchi-KeluoXiaogulihe potassic volcanic field(EWKX for short)in the Songliao Basin of NE China,with a combination of the previous olivine and whole-rock geochemical data.We 相似文献
Steel piles at the tidal zone can be seriously corroded. Common protective methods such as painting or coating with rubber
or other protective materials, etc. cannot provide full protection when used as supplementary protection because these traditional
methods require strict pretreatment and sealing of the metallic surface from the corrosive mediums, and time for the protective
coatings to solidify. This is very difficult under the severe action of waves and surges on the sea.
With our oil-soluble DZ-2 tape, protection efficiency for hanging steel plates at the tidal and splash zones reaches to 82–99%.
The protection efficiency of water soluble DZ tape at the tidal zone reaches to 92.9%. The DZ and DZ-2 tapes can rapidly reduce
the original corrosion velocity to ten percent and one percent respectively as fully proved by the 500 hour rapid corrosion
testing with indoor salt fog and by the relevant electrochemical parameters of instantaneous corrosion velocity, etc.
DZ tape absorbs much OH− to cause a pH rise. A synergistic protective effect is gained when DZ tape is used together with cathodic protection of steel
piles at the tidal zone. The working principle of DZ tape is different from that of DZ-2 tape even though they are composed
of the same chemical materials. The latter provides protection because of the close affinity between metal and its carboxyl
group shields the active centre at the metal surface to reduce the activation energy of metal. The carbon chain forms a covering
oil film of netted structure.
Dai Tao, Dai Wei and Xia Caiyuan et al. participated in the research and made useful contribution. Contribution No. 1656 from
the Institute of Oceanology, Academia Sinica. 相似文献