Landslide at Su-Hua Highway 115.9k triggered by Typhoon Megi in Taiwan   总被引：2，自引：2，他引：0  

Chia-Ming Lo  Ching-Fang Lee  Hsien-Ter Chou  Ming-Lang Lin 《Landslides》2014,11(2):293-304

This study focused on the landslide case at Su-Hua Highway 115.9k, Taiwan. A preliminary investigation was conducted on geomorphologic features change and landslide mechanisms using digital elevation models, geographical maps, and remote sensing images at different times in conjunction with geological surveys and analysis results. Using the results of geological surveys and physical model experiments, we constructed a discrete element method to simulate the process of landslide movement. The results revealed deformation in the metamorphic rock slopes upstream of 115.9k. The slopes around the erosion gully upstream presented visible slope toes cutting and tension cracks at the crest as well as unstable rock masses. According to the results of numerical simulation for typhoon Megi event, intense rains could induce slippage in the rock debris/masses in the source area, initially at a speed of 5–20 m/s. Subsequently, steeper terrain could cause the rock debris/masses to accelerate to form a high-speed (>30 m/s) debris slide quickly moving downstream to form an alluvial fan downstream by the sea.  相似文献   

长江中游高位砾石层的磁性特征与物源分析     

张玉芬  李长安  周稠  康春国  熊德强  江华军 《吉林大学学报(地球科学版)》2014,(5):1669-1677

在长江中游分布着一些高位的砾石层,尤其是在宜昌与武汉的阳逻附近。为了探讨这些砾石层的磁性特征及物质来源,对它们进行了磁性特征研究,结果表明:1不同砾石层剖面磁性物质的含量明显不同,其中云池砾石层磁性物质的含量最高,善溪窑、红花套、白洋渡砾石层次之,阳逻砾石层含量最低。2SIRM/χ和F300值显示,长江中游砾石层磁性矿物类型主要是磁铁矿等亚铁磁性矿物,其中阳逻砾石层不完全反铁磁性矿物含量比例比其他砾石层高。3χARM/χ、χARM/SIRM、χfd值表明,白洋渡、红花套及善溪窑砾石层的磁性矿物中以较粗的磁性颗粒为主,而云池和李家院的磁性矿物颗粒都较细,武汉阳逻砾石层的磁性颗粒以单畴、超顺磁颗粒为主。4宜昌附近的善溪窑、云池、白洋渡、红花套砾石层的磁性特征与长江现代沉积物的特征接近,指示其物质主要来自于长江沉积物;而阳逻砾石层的磁性特征却与江汉平原周边河流的现代沉积物磁性特征有些类似,结合野外砾石层岩性特征,认为阳逻砾石层是长江、汉江与江汉平原周边河流共同作用的产物。  相似文献   

Optimized object-based image classification: development of landslide knowledge decision support system     

Shiuan Wan  Tsu Chiang Lei  Tein Yin Chou 《Arabian Journal of Geosciences》2014,7(5):2059-2070

Landslide spatial decision support systems (LS-DSS) are computer-based systems that combine the geographic storage, search, and retrieval capabilities of geographic information systems with the decision models and optimizing algorithms used to support decision-making for landslide problems. This study proposes an optimization process of region object-oriented classification (ROC) to analyze the landslide image information. The surface information from the Wan Da reservoir area is collected and studied. We collected different spectrum with several texture information to analyze the surrounding area of the Wan Da reservoir. ROC is used to classify the landslide area. Entropy-based classification is used as a classifier in ROC to determine the landslide/nonlandslide area. The parameters of S (similarity) and A (area) are used and then the best combinations are found. An optimize algorithm is developed to access the above variables to perform the best classification outcomes. The relations of occurrence vs. non-occurrence of landslide which are linked to the attributes of land surface are studied. An improved translation model (Expert Knowledge Translation Platform) is also presented to increase the accuracy. This could be of help to manage/monitor the landslide area near the reservoir.  相似文献   

塔里木西北缘阿克苏地区大陆拉斑玄武岩对新元古代裂解事件的制约   总被引：11，自引：4，他引：7  

王飞  王博  舒良树 《岩石学报》2010,26(2):547-558

塔里木西北缘新元古界苏盖特布拉克组不整合覆盖在前寒武纪阿克苏群蓝片岩及侵入其中的基性岩墙之上,苏盖特布拉克组底部发育两层玄武岩夹层,其形成时代和成因背景对认识塔里木板块前寒武纪构造演化及有关的超大陆循环和地球动力学过程具有重要意义。本文对这两层玄武岩进行了全岩地球化学和锆石U-Pb年代学研究。结果显示,玄武岩均属于大陆拉斑玄武岩系列,微量元素地球化学特性与典型的大陆溢流玄武岩非常相似,其岩浆来源于富集地幔,并遭受了一定程度的地壳混染作用。玄武岩中锆石的LA-ICP-MS U-Pb年龄分布在1945~755Ma,这些锆石均属于玄武岩浆上升过程中从地壳岩石捕获的继承锆石,记录了塔里木北缘元古代期间多期变质和岩浆事件。这一年龄范围表明,玄武岩形成的时代应晚于755Ma。本文的研究结果表明,阿克苏大陆拉斑玄武岩形成于板内裂谷环境,可能与新元古代Rodinia超大陆之下的地幔柱活动有关,是塔里木板块从Rodinia超大陆裂解出来的直接证据。  相似文献   

Application of wavelet‐based multi‐model Kalman filters to real‐time flood forecasting     

Chien‐Ming Chou  Ru‐Yih Wang 《水文研究》2004,18(5):987-1008

This paper presents the application of a multimodel method using a wavelet‐based Kalman filter (WKF) bank to simultaneously estimate decomposed state variables and unknown parameters for real‐time flood forecasting. Applying the Haar wavelet transform alters the state vector and input vector of the state space. In this way, an overall detail plus approximation describes each new state vector and input vector, which allows the WKF to simultaneously estimate and decompose state variables. The wavelet‐based multimodel Kalman filter (WMKF) is a multimodel Kalman filter (MKF), in which the Kalman filter has been substituted for a WKF. The WMKF then obtains M estimated state vectors. Next, the M state‐estimates, each of which is weighted by its possibility that is also determined on‐line, are combined to form an optimal estimate. Validations conducted for the Wu‐Tu watershed, a small watershed in Taiwan, have demonstrated that the method is effective because of the decomposition of wavelet transform, the adaptation of the time‐varying Kalman filter and the characteristics of the multimodel method. Validation results also reveal that the resulting method enhances the accuracy of the runoff prediction of the rainfall–runoff process in the Wu‐Tu watershed. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

Simplified formulae system for resonant inverse Compton scattering of a fast electron in an intense magnetic field     

J. H. You  W. P. Chen  S. N. Zhang  L. Chen  D. B. Liu  C. K. Chou 《Monthly notices of the Royal Astronomical Society》2003,340(2):687-693

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利用时间序列ALOS-2 PALSAR数据监测输电通道地表形变     

李宏伟  谭衢霖  谢酬 《测绘与空间地理信息》2021,44(6):46-50,53

有效监测西南地区输电线路的地表形变对我国电网的安全平稳运行具有重要意义.本文以特高压输电通道沿线为研究区域,基于时间序列卫星雷达差分干涉测量技术,利用2016年8月15日至2017年10月9日22景5 m分辨率升轨的ALOS-2 PALSAR雷达卫星数据,采用PS-InSAR处理方法,在植被覆盖茂密的西南地区对某输电通道滑坡灾害开展地表形变监测研究.结果表明,在距离输电线杆塔约4.4 km的下沟坪村附近发现明显地表变形,最大的滑坡点形变速率达到了30 mm/year.监测结果与现场核查具有很好的一致性,验证了基于时间序列ALOS-2 PALSAR数据在输电通道变形监测领域的可靠性,在复杂山区的形变监测方面具有很好的应用前景.  相似文献   

Measuring the orbital periods of low mass X-ray binaries in the X-ray band     

Yi Chou 《中国天文和天体物理学报》2014,(11)

A low mass X-ray binary(LMXB) contains either a neutron star or a black hole accreting materials from its low mass companion star. It is one of the primary astrophysical sources for studying stellar-mass compact objects and accreting phenomena. As with other binary systems, the most important parameter of an LMXB is the orbital period, which allows us to learn about the nature of the binary system and constrain the properties of the system's components, including the compact object. As a result, measuring the orbital periods of LMXBs is essential for investigating these systems even though fewer than half of them have known orbital periods. This article introduces the different methods for measuring the orbital periods in the X-ray band and reviews their application to various types of LMXBs, such as eclipsing and dipping sources, as well as pulsar LMXBs.  相似文献   

一种新型人工“流体包裹体”：融合二氧化硅毛细管技术          下载免费PDF全文

倪培  丁俊英  I-Ming Chou  Jean Dubessy 《地学前缘》2011,18(5):132-139

利用融合二氧化硅毛细管技术制作了纯H2O体系、纯CO2体系、H2O-NaCl体系和H2O-CO2体系的人工包裹体样品,并对样品进行了显微测温和激光拉曼光谱测试工作。实验结果显示毛细管样品中的流体成分具有代表性,而且常规的流体包裹体显微测温和显微激光拉曼光谱分析技术完全适于毛细管样品的测试。对样品的显微测温和拉曼光谱研究...  相似文献   

Eco-environmental impact assessment of pre-leisure beach nourishment on the benthic invertebrate community at Anping coast   总被引：1，自引：0，他引：1  

Chun-Han SHIH  Ta-Jen CHU  Wen-Chieh CHOU  Wei-Tse CHANG  Ying-Chou LEE 《中国海洋工程》2011,25(2):215-236

In recent years,owing to global warming and the rising sea levels,beach nourishment and groin building have been increasingly employed to protect coastal land from shoreline erosion.These actions may degrade beach habitats and reduce biomass and invertebrate density at sites where they were employed.We conducted an eco-environmental evaluation at the Anping artificial beach-nourishment project area.At this site,sand piles within a semi-enclosed spur groin have been enforced by use of eco-engineering concepts since 2003.Four sampling sites were monitored during the study period from July 2002 to September 2008.The environmental impact assessment and biological investigations that we conducted are presented here.The results from this study indicate that both biotic(number of species,number of individual organisms,and Shannon-Wiener diversity) and abiotic parameters(suspended solids,biological oxygen demand,chemical oxygen demand,dissolved inorganic nitrogen,dissolved inorganic phosphorus,total phosphorus,total organic carbon,median diameter,and water content) showed significant differences before and after beach engineering construction.Biological conditions became worse in the beginning stages of the engineering but improved after the restoration work completion.This study reveals that the composition of benthic invertebrates changed over the study period,and two groups of organisms,Bivalvia and Gastropoda,seemed to be particularly suitable to this habitat after the semi-enclosed artificial structures completion.  相似文献