Reading Lanyu's tourism landscape: Hybridity and identity on Orchid Island,Taiwan

This article analyses the creation and implications for cultural identity of a hybrid tourism landscape on Taiwan's Orchid Island (Lanyu). It particularly argues that Lanyu's native Tao people have begun to gain a somewhat stronger cultural identity and autonomy through this landscape. Orchid Island underwent rapid modernization within the past 60 years. The article not only shows how tourism was imposed by Taiwan's government, but also how the Tao have made greater use of tourism's landscape over time for their own purposes. Not without sociocultural problems and contradictions, Lanyu's tourism landscape has been polysemic enough to allow for gradually improving relationships between Taiwanese and Tao and for gradually increasing Tao participation in modernity on their own terms.     

输电线路倾斜铁塔原位加固纠偏关键技术研究

输电线路铁塔属高耸结构,不同于一般建筑物,输电线路电塔加固纠偏有其特殊性。结合厦门电业局所辖110 kV输电线路倾斜铁塔加固纠偏工程实例,深入探讨了输电线路倾斜铁塔加固纠偏关键技术。分析了铁塔倾斜原因,应用FEM技术研究基础倾斜对塔身的应力和变形的影响机制,分析了倾斜铁塔的健康状况,在此基础上提出经济有效的加固纠偏设计方案;对加固纠偏设计计算方法、加载控制指标分析及信息化施工控制等关键技术展开了讨论,并指出需要进一步研究的问题。     

海南岛北西部邦溪地区奥陶纪火山-碎屑沉积岩岩石学、矿物学和地球化学:源区及构造环境暗示

海南岛奥陶纪火山-碎屑沉积岩矿物、地球化学成分与源区岩性质和沉积构造环境密切相关.岩相学观察和矿物化学分析表明,所研究的岩石主要碎屑矿物由石英、绿泥石(Si:5.8～6.2 a.p.f.u.、Mg/(Mg Fe):～0.45)和自色云母(Si:6.2～6.8 a.p.f.u.、Al:4.5～5.7 a.p.f.u.)组成,含少量的长石(主要为钾长石)、黑云母(Mg/(Mg Fe)=0.43、TiO2=0.01%)和磷灰石等矿物.地球化学特征上,这些岩石普遍具有高SiO2含量(Al2O3/SiO2=0.07～0.19)、相对高的K2O/Na2O比值(1.25～14.71)和高的FeOtotal MgO含量(普遍大于5%,最高达11.5%),但微量元素(含REE)含量普遍低于PAAS(NASC),且REE分布模式显示LREE富集((La/Yb)N=6.1～12.5)、Eu负异常或弱负异常(δEu=0.57～0.86).高的前交代CIA(～84)和PIA(～85)指数、A-CN-K分布模式以及可变的Th/U(2.9～25)比值还说明源区已经历强烈的化学和机械风化作用.低的Ce/Pb比值(2.1～2.8)则反映海南岛早古生代地壳已经历过Pb的富集事件.结合矿物化学成分和区域地质对比,研究区奥陶纪火山-碎屑沉积岩源区主要由变质的岩浆弧花岗闪长岩和弧长英质火山岩组成,少量的铁镁质成分不能排除,因而暗示一个从活动大陆边缘到被动大陆边缘的过渡性沉积构造环境.同时,推测海南岛在早古生代和晚古生代-早中生代可能分别存在一次俯冲增生-碰撞造山事件;海南岛(可能包括华夏地块)应于晚奥陶世后才脱离东冈瓦纳大陆的澳大利亚边缘.     

海啸波对近岸岛礁影响的数值模拟研究

基于Okada有限断层模型和非线性浅水波方程,结合高精度嵌套网格建立了越洋（中国近海）-局部-近岸岛礁的海啸生成与传播的数值模型。以三亚凤凰岛为例,首先针对2011日本地震海啸,模拟分析了海啸波沿中国沿海大陆架的传播特征及对凤凰岛的影响规律。在取得验证结果的基础上,进一步讨论了中国近海的马尼拉海沟和琉球海沟的潜在海啸源,以及环太平洋的21个潜在特大越洋海啸对凤凰岛的影响特征。依据海啸波在抵达凤凰岛的波浪特征,结合傅里叶频谱分析方法,探索了近岸岛礁对海啸波的放大效应。结果表明,中国近海一般震级的海啸和特大越洋海啸对凤凰岛存在一定影响,最大波幅接近1 m,传播时间从3 h到27 h不等。受三亚东南半岛的影响,琉球海沟激发的海啸和越洋海啸在凤凰岛的放大效应相对于马尼拉海沟较小,其频率集中在0.8×10-4~2×10-4 Hz。马尼拉海沟产生的海啸波在凤凰岛产生了较为显著的放大效应,对于凤凰岛是值得关注的高风险海啸源。     

海南岛温泉特征与地下热水成因

通过对海南岛区域地质构造、岩浆岩与温泉分布的关系,以及温泉水化学和同位素分析,总结该区温泉的属性特征,阐明地下热水的成因。温泉在地势较低的琼西北和琼东南呈对称性条带状分布。水质类型大多为低矿化的重碳酸盐型,呈碱性,含较高的氟和硅;第四系滨海区受海水影响则表现为氯化钠型。温泉的氢、氧、氦同位素及气体组分揭示地下热水起源于大气降水,大气降水在地壳浅部循环过程中被围岩加热成地下热水。地热资源为中低温对流型地热系统,热储温度为59.5～161.2 ℃,平均128.5℃,是由偏高的区域热流在深部供热的,与岩浆作用无关。地下热水的出露受区内NE、EW向深大断裂控制。     

Seasonal variation in community structure and body length of dominant copepods around artificial reefs in Xiaoshi Island, China

This study aims to investigate the seasonal variations in copepod community structure and prosome length of dominant species from March 2009 to January 2010 around artificial reefs in Xiaoshi Island,Yellow Sea,Weihai,China.Samples were collected using two types of plankton net(Model I and Model II) for different-sized copepods.The number of taxon was calculated from the data of both the net types,while the copepod abundance was done using the samples from Model II only.Sixteen species of planktonic copepods,including 5 dominant species,were recorded.Results reveal that Oithona similis was the first dominant species from March to June,and was replaced by Paracalanus parvus in September;both dominated the copepod community in January.Acartia hongi was the second dominant species from March to September.Centropages abdominalis was the third dominant species from March to June,and was replaced by O.similis in September and Corycaeus affinis in January.C.affinis was the fourth dominant species in September.Population density of the dominant copepods was compared with that of other similar regions.We found that the dominant species were mostly small copepods(<1 mm) except for adult Centrapages abdominalis.Seasonal variation in prosome length of O.similis,C.abdominalis,and C.affinis,and their copepodites were studied for the first time in China.For P.parvus and A.hongi,seasonal trends in prosome length variation were similar with those in Jiaozhou Bay,Yellow Sea,Qingdao,China,in a similar temperate domain.The results are helpful for future calculation of copepod biomass and production,and for investigation of the relationship between copepods and fish resources.     

Magmatic relationships and ages of Caribbean Island arc tholeiites, boninites and related felsic rocks, Dominican Republic

Located in the Cordillera Oriental of the Dominican Republic, the Early Cretaceous Los Ranchos Fm (LRF) comprises a > 3-km thick sequence of volcanic and volcaniclastic rocks with variable geochemical characteristics, which is intruded by tonalite batholiths, minor gabbro/diorite plutons and mafic dykes. From top to bottom, three main stratigraphic units have been mapped: upper basaltic, intermediate rhyodacitic and lower basaltic. Combined detailed mapping, stratigraphy, geochemistry, Rb–Sr/Sm–Nd isotopic studies and U–Pb/Ar–Ar geochronology show that the mafic rocks of the LRF include boninites and LREE-depleted island arc tholeiites (IAT) in the lower unit, both which appear genetically related, whereas normal IAT occur in the upper unit. The source for these rocks is thought to reflect variably depleted mantle, overprinted by a subduction zone component. Contemporaneous Aptian U–Pb zircon ages were obtained for a rhyodacite from the intermediate unit (116.0 ± 0.8 Ma) and a tonalite of the Zambrana batholith (115.5 ± 0.3 Ma) that intrudes the LRF. The similarity of trace element signatures in both units argues for genetic link between the felsic volcanics of the LRF and the tonalite plutonism. Low-K rhyolites and tonalite batholiths are interpreted as products of secondary melting at the base of thickened early arc crust. ⁴⁰Ar/³⁹Ar plateau ages of hornblende in most tonalites are Albian (109–106 Ma) and interpreted as final cooling ages, prior to unroofing and growth of unconformable overlying reef limestones of the Hatillo Fm (112–100 Ma). The LREE-depleted IAT and boninites of lower basaltic unit are interpreted to have formed during subduction zone initiation in the Caribbean Island arc, and the normal IAT of the upper unit are thought to represent the subsequent establishment of the volcanic front.     

海南岛海岸线变迁遥感监测与分析

监测和了解海岸线的动态变化对海岸带防护、海岸资源的合理开发和利用具有重要意义。本文以Landsat TM/OLI影像为数据源,通过Canny边缘检测算子提取1990年、2000年、2010年和2015年的海南岛海岸线,获取岸线长度以及陆地面积变化等信息,分析了海南岛25 a年来的海岸线时空变化特征。结果表明:1990—2015年海南岛海岸线总长度增加33.58 km,海岸线总体向海推进,沿岸陆地面积呈增加的趋势;岸线变迁主要集中在北岸和东岸,人工岸线长度增长显著,淤泥质岸线等自然岸线长度减少;海岸线变化主要受人为因素影响,海岸开发方式呈现出多样化,以围垦养殖、城镇建设和港口码头建设为主。     

A NUMERICAL STUDY ON THE FORMATION AND DEVELOPMENT OF ISLAND-INDUCED CYCLONE AND ITS IMPACT ON TYPHOON STRUCTURE CHANGE AND MOTION

In this paper,the impact of the Taiwan Island topography on the structure change and motion ofTyphoon Dot(9017)during its crossing the Taiwan Island is studied with a modified version of aJMA operational regional model(Japan spectral model,JSM).A series of sensitivity experiments areconducted to detect the forming and developing mechanism of an island-induced cyclone.Results showthat lee side low pressure center plays a very important role in the formation of the induced-cyclonewhile a typhoon is approaching a large island with high mountains.The position and intensity of theinduced cyclone is sensitive to the height and location of island mountain,intensity of TC and under-lying surface topography distribution as well.A preliminary formation criterion of the island-inducedcyclone is obtained.     

Sinkhole subsidence due to mining

This paper reviews the modes of formation of sinkhole subsidence associated with mining activities, drawing on examples in India. Sinkhole (pot-hole) subsidence is an abrupt local depression at the surface which can be hazardous to life and property due to its tendency to occur without warning. Shallow extraction, weak overburden and geological discontinuities are the main factors which cause them. Sinkholes occur due to the failure of a mine roof which migrates through the overlying strata until the failure zone intercepts the unconsolidated overburden. Alternatively they may occur by the creation of cavities in the overburden following the inflow of sand and soil from the overlying weathered and friable strata through faults. Overburden cavities eventually cave in and sinkholes appear at the surface. Sinkholing phenomena can be controlled to some extent by proper design of mining supports and construction of walls to create a barrier around an area prone to sinkholes in bord and pillar workings. Backfilling and grouting can be used to stabilize abandoned underground workings.