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121.
Catastrophic flooding associated with sea-level rise and change of hurricane patterns has put the northeastern coastal regions of the United States at a greater risk. In this paper, we predict coastal flooding at the east bank of Delaware Bay and analyze the resulting impact on residents and transportation infrastructure. The three-dimensional coastal ocean model FVCOM coupled with a two-dimensional shallow water model is used to simulate hydrodynamic flooding from coastal ocean water with fine-resolution meshes, and a topography-based hydrologic method is applied to estimate inland flooding due to precipitation. The entire flooded areas with a range of storm intensity (i.e., no storm, 10-, and 50-year storm) and sea-level rise (i.e., current, 10-, and 50-year sea level) are thus determined. The populations in the study region in 10 and 50 years are predicted using an economic-demographic model. With the aid of ArcGIS, detailed analysis of affected population and transportation systems including highway networks, railroads, and bridges is presented for all of the flood scenarios. It is concluded that sea-level rise will lead to a substantial increase in vulnerability of residents and transportation infrastructure to storm floods, and such a flood tends to affect more population in Cape May County but more transportation facilities in Cumberland County, New Jersey.  相似文献   
122.
阿尔泰超高温变泥质麻粒岩的锆石U-Pb年龄及其地质意义   总被引:1,自引:1,他引:1  
仝来喜  陈义兵  徐义刚  周信  刘兆 《岩石学报》2013,29(10):3435-3445
最近我们通过岩相学观察和矿物温压计算,首次确定了在阿勒泰喀拉苏附近存在超高温变泥质麻粒岩,其矿物组合为石榴石+斜方辉石+夕线石+堇青石+尖晶石+黑云母+斜长石+石英等。斜方辉石成分具有高铝特点,其Al2O3含量高于8.0%,指示了其峰期变质作用达到了超高温(>900℃)的条件。P-T计算结果显示其峰期变质条件为:P=~8.0kb, T=~960℃。初步P-T估算结果表明了一个峰期后近等压冷却的逆时针P-T轨迹。我们对其中锆石进行了LA-ICP-MS U-Pb年龄测定,年龄结果主要分布于260~280Ma之间,具有峰值年龄271±5Ma,个别年龄为380~390Ma,继承锆石主要分布于450~500Ma之间。该年龄结果表明阿尔泰超高温变质事件发生于二叠纪,在时间上与二叠纪塔里木地幔柱活动的时间(~275Ma)高度一致,且也和该区广泛的二叠纪(260~280Ma) 后造山或非造山的基性岩和花岗岩侵入是同时的。因此,阿尔泰二叠纪超高温变泥质麻粒岩的形成,可能与由二叠纪塔里木地幔柱活动引起的岩浆底侵和下地壳伸展加热密切相关,这也与该超高温变泥质麻粒岩的逆时针P-T轨迹所反映的构造背景一致。  相似文献   
123.
化学和稳定同位素指纹是目前国际上用于示踪石油类污染来源及其环境命运的有效技术。通过气相色谱-质谱(GC—MS)分析可疑重油与被污染水体及植物表面污染物的饱和烃和芳烃分布以及生物标志化合物姥姣烷、植烷、“不可分辨的混合物”(UCM)等化学指纹特征,对比可疑重油与被污染水体表面漂浮重油的沥青质同位素组成,追踪了发生在广东省南海市的两次小型重油泄漏事件。结果揭示,2002年10月16日晚发生的污染事件源于某饲料公司锅炉房的重油泄漏;而2002年10月25日的泄漏事故则是某加油站重油渗漏所致。  相似文献   
124.
开敞水域中航槽流场的数值模拟   总被引:2,自引:0,他引:2       下载免费PDF全文
建立了一个模拟开敞水域中航槽流场的平面二维数学模型.利用该模型计算得到的流速分布与袁美琦、李安中等人试验值相吻合,并计算了相当于天然情况下(各种水深、挖深比及航槽与水流的不同交角)的流场,得到了各种航槽与水流交角、不同挖深比的航槽流速折减系数变化规律图,及各种航槽与水流交角、不同挖深比的航槽中流向与航槽轴线交角的变化规律图,为开敞水域中航槽选线设计提供了依据.  相似文献   
125.
The zircon SHRIMP dating of the Zhangtiantang granite gave an age of 159±7 Ma., which shows that the granite was produced at the early Late Jurassic. The Ar-Ar plateau ages of biotite and K-feldspar from the Zhangtiantang pluton are 153.2±1.1 Ma and 135.8±1.2 Ma, respectively. The Ar-Ar anti-isochrone ages of biotite and K-feldspar are 152.5±1.7Ma and 135.4±2.7Ma, respectively. The ages represent the isotopic closure ages of minerals in the pluton. The Zhangtiantang granites are regarded as peraluminous crust-derived type granites to possess the typical geochemical characteristics of calc-alkaline rocks on continental margin, with enriched Si, K, Al (average value of A/CNK as 1.18), HREE, Rb, U, and Th, heavily depleted V, Cr, Co, Ni, Ti, Nb-Ta, Zr, Sr, P, and Ba, strongly negative Eu and common corundum normative (average value of C as 1.84). The εNd(t) values of the Zhangtiantang granite are −5.84 to −7.79, and t 2DM values are 1.69 to 1.83 Ga, which indicates partial melting of continental-crust metamorphic sedimentary rocks during the Middle Proterozoic. The cooling history of the Zhangtiantang granitic pluton indicates that the cooling velocity of pluton was faster (about 67°C/Ma) from zircon (158 Ma) to biotite (152 Ma), and was slower (about12°C/Ma) from biotite (152.5 Ma) to K-feldspar (135.8 Ma). It can be deduced that the temporal gap (about 10 Ma) between the granite formmation and W-Sn mineralization in South China may be related to ordinary magma-hydrothermal processes by the variational cooling curve of the pluton. The Zhangtiantang pluton was formed in a compressive setting, with differentiation evolution and mineralization occurring in a relative relaxation setting.  相似文献   
126.
This study uses an incompressible smoothed‐particle hydrodynamics model to investigate the interaction between dry granular material flows and rigid barriers. The primary aim is to summarise some practical guidelines for the design of debris‐resisting barriers. The granular materials are modelled as a rigid‐perfectly plastic material where the plastic flow corresponds to the critical state. The coupled continuity equation and momentum equation are solved by a semi‐implicit algorithm. Compared with flows in controlled flume experiments, the model adequately reproduces both the kinetic of the flows and the impact force under various conditions. Then the numerical simulations are used to study the detailed interaction process. It is illustrated quantitatively that the interaction force consists of two parts, ie, the earth pressure force caused by the weight of the soil and a dynamic force caused by the internal deformation (flowing mass on top of a dead zone). For the estimation of impact load, this study suggests that an increased earth pressure coefficient depending on the Froude number should be incorporated into the hydrostatic model.  相似文献   
127.
The Lehong zinc-lead deposit is one of the new-found large Zn-Pb deposits in the Sichuan- Yunnan-Guizhou Zn-Pb poly-metallic mineralization area. The ore-bodies of the Lehong deposit are strictly controlled by structures, and the fault tectonites can be divided into four groups which include morbruk rock, cataclastic rock and tectonic breccia. The mechanical properties of the faults suggest that there are five tectonic systems formed in the Caledonian-early Hercynian, Indosinian-early Yanshanian, mid-Yanshanian, late Yanshanian and Himalayan periods, respectively. The Lehong fault and the Qiaojia-Lianfeng fault are two important ore-controlling structures which might have acted as channel ways of the ore fluids. The ores are hosted in the subordinary fracture zone, joint fracture zone and interlayer fault zones in trailing folds of the Lehong fault and the Baobaoshang syncline and Jinjiagou anticline. Hence, the Lehong deposit is a tectonic -controlled ore deposit. These research do not only lay a foundation for studying deposit genesis and ore-finding direction in the Lehong deposit, but also provides important enlightenments for the ore-finding prognosis of lead-zinc deposits in northwestern Guizhou ore concentration district. © 2018, Science Press. All right reserved.  相似文献   
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He  Longfei  Hu  Chenglin  Zhao  Daozhi  Lu  Haili  Fu  Xiaoxi  Li  Yiyu 《Natural Hazards》2016,84(1):179-207
Along with carbon emission regulations launched by governments and consumers’ rising concerns about climate changes and global carbon footprint, interests of academia and industry have risen in carbon-efficient supply chain management. This research focuses on some product supply chain to make a literature review-based investigation on proposing a theoretical framework. We also solve potential research issues of how diverse carbon emission regulations can work on supply chain performance as well as emission; in what way we can find coordination mechanisms and optimal policies for supply chain operations to abate emission and enhance system profitability within different scenarios; and also to evaluate the effect on emission reduction for each emission regulation aforementioned through comparing their associated supply chain performances and system emission. Both practitioners in industry and academia might find this study useful, as it generates concepts with a formal framework of potential and values theoretical issues in the emerging field of carbon-efficient supply chain management which combines carbon emission regulations with mature operation management to enrich the theory of supply chain management. This study is perhaps to be valuable and constructive both for operational decisions in firms and for the enactment as well as implementation of emission-reduction regulations. This study should activate further potential researches.  相似文献   
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