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31.
BOOK REVIEWS     
Book Reviewed in this article: Marine Resources of Kuwait: Their Role in the Development of Non-oil Resources . Fatimah H. Y. al -Abdul -Razzak Recollections of a Revolution: Geography as Spatial Science . Mark Billinge , Derek Gregory and Ron Martin Entre l'Eden et l'Utopie . Luc Bureau Developments in Political Geography . M. A. Busteed The Elements of Graphing Data . William S. Cleveland Rural Resource Management . Paul J. Cloke and Chris C. Park Third World Atlas . Ben Crow and Alan Thomas Exploitation, Conservation, Preservation: A Geographic Perspective on Natural Resource Use . Susan L. Cutter , Hilary Lambert Renwick, and William H. Renwick . Wine Regions of the Southern Hemisphere . Harm Jan de Blij Regional Development: Problems and Policies in Eastern and Western Europe . George Demko The Geographer at Work . Peter R. Gould Change in the Amazon Basin . John Hemming Geography Since the Second World War . R. J. Johnston and P. Claval Urbanization in China: Town and Countryside in a Developing Economy 1949–2000 A.D. , R. J. R. Kirkby Transport and Communications for Pacific Microstates: Issues in Organisation and Management . Christopher C. Kissling Fluvial Forms and Processes . David Knighton The Urban Millennium . Josef W. Konvitz Technological Transition in Cartography . Mark Stephen Monmonier Field Guide to Soils and the Environment: Applications of Soil Surveys . Gerald W. Olson Northern Australia: The Arenas of Life and Ecosystems on Half a Continent . Don Parkes A Killing Rain: The Global Threat of Acid Rain . Thomas Pawlick From the Family Farm to Agribusiness: The Irrigation Crusade in California and the West, 1850–1931 . Donald J. Pisani Hybrid Maize Diffusion in Kenya . Franz -Michael Rundquist Warning and Response to the Mount St. Helens Eruption . Thomas F. Saarinen and James L. Sell Coastal Geomorphology in Australia . B. G. Thom Tropical Rain Forests of the Far East , 2nd ed . T. C. Whitmore The Dark Side of the Earth . Robert Muir Wood Categorical Data Analysis for Geographers and Environmental Scientists , Neil Wrigley  相似文献   
32.
The model of the Poisson point process is too vague for earthquake locations in space and time: earthquakes tend to cluster in middle distances and to repulse in large ones. The Poisson point model with variable density makes it possible to describe the tendency for clustering but does not reveal the periodicity of clusters. The author proposes the point-process model where locations of points are determined not by densities of point distribution, but by densities of interpoint differences distribution. In the model, a latent periodicity is revealed and used for prediction of a point process. In 1983, the point-process model prediction was made for the Kuril Islands for 1983–1987 and two signs of danger in time and location were determined. Then they were confirmed by strong earth-quakes. In 1989, a similar prediction was made for North Armenia. The Spitak earthquake in 1988 is clearly seen from the data of previous earthquakes.  相似文献   
33.
A number of bitumen samples have been recovered from vugs and fractures in outcropping Tertiary basalts of the Queen Charlotte Islands off the west coast of British Columbia, Canada. n-Alkanes and acyclic isoprenoids are not present and the polycyclic biomarker distribution of the four samples analyzed by GC and GC-MS has been altered. One sample contains no remaining recognizable biomarkers. Two bitumens were also obtained from Lower Jurassic potential source rocks, including one from the Sandilands Formation, which was considered previously to be the most likely source of the Tertiary bitumens. Although these two bitumens were also taken from outcrops, they are considerably less biodegraded. The Sandilands Formation bitumen contains 28, 30-bisnorhopanes and since these compounds were not detected in the Tertiary bitumens, there is no evidence from the initial results for a Sandilands Formation contribution to the hydrocarbons in the Tertiary basalts. The presence of 18α(H)-oleanane in the saturate fraction of two of the Tertiary bitumens from widely separated locations indicates that they are at least partially sourced from Tertiary organic matter.Because the distribution of biomarkers in some samples has been severely affected by biodegradation, the asphaltenes of the bitumens were hydrously-pyrolysed and the saturate fractions of the resulting pyrolysates analysed for possible additional information on the origin of the bitumens. The pyrolysates from the more degraded samples contain compounds not detected in the saturate fractions of the original bitumen and show some of the expected characteristics of the original non-degraded bitumen. However, the compounds most useful for correlation are not present in the pyrolysates apparently due to their non-incorporation into the kerogen macromolecule. Our results suggest that hydrous-pyrolysis of asphaltenes is of limited use in the correlation of biodegraded samples and in determining their origins.  相似文献   
34.
La Cueva del Llano is a volcanic tube of Pleistocene age on Fuerteventura Island, in the Canary Islands. Part of it is infilled with sediments of external origin. These deposits are exceptional in stratigraphic complexity and thickness compared with other known tube infillings, and they comprise nine stratigraphic units deposited in five phases. In Phase I, which has not been dated, sedimentation of cinder from a nearby cone occurred. Phase II began ca. 16,830 ± 900 14C yr B.P., whereas phase IV dates to 9280 ± 370 14C yr B.P. The interpretation of sedimentary features shows that phases III and V correspond to a dry climate, similar to the present one, whereas the climate was much wetter during phases II and IV. This paleoclimatic sequence agrees with those suggested by the study of deposits formed in other sedimentary environments, not only in Fuerteventura but on other islands of the Canary group and the Sud-Maroc region.  相似文献   
35.
掌握北极海水水质特征及地域分布等第一手数据对北极科考意义重大。该项研究工作是全国青少年北极科考子任务,于2017年夏季在北极斯瓦尔巴德群岛中部海域对表层海水水质特征、地域差异及相关控制因素进行了研究。选取了6个区域共40个采样点采集表层海水样本,从温度、酸碱度、电导率、溶解性总固体量、实际盐度和溶解氧饱和度等方面进行了水质特征测量分析,发现该海域6个区域在海水温度、电导率、溶解性总固体量、实际盐度及溶解氧饱和度等方面均有较大差异,而酸碱度差异不大: 北部冰区水温最低,溶解性总固体量最低,溶解氧含量较高; 西北部海湾溶解氧饱和度最高; 中部海峡溶解性总固体量最高,盐度和电导率最低; 南部海域水温最高,实际盐度和电导率最高,溶解氧饱和度最低; 东部沿海水温偏低。采样点地理位置、洋流情况、地形地貌等因素对表层海水水质均有影响。这些研究成果对补充我国在北极地区的第一手科考数据和进行深入的科考研究具有重要意义。  相似文献   
36.
崎岖列岛海域表层沉积物平均粒径在0.1~0.2 mm之间的细砂通常具有较好的分选性,平均粒径细于4Φ的沉积物通常分选性较差;平均粒径在4.5Φ~7.5Φ的沉积物通常表现为正偏态,且粒度越粗,偏度越正偏;平均粒径粗于4Φ的砂质沉积物偏度无显著的正偏或负偏倾向;崎岖列岛海域中值粒径位于4Φ~5Φ的样品数较少,因该粒级位于悬移质与跃移质之间。  相似文献   
37.
Black band disease(BBD),characterized by the Cyanobacterial dominated pathogenic consortium,is thought to play a key role in the global decline of the coral reef ecosystems.The present paper originally documents a case of BBD from Yongxing Island(Xisha Islands,South China Sea),and further probes the reasons of this abnormal phenomenon.Prior to 2007,corals at northern reef-flat of Yongxing Isand were in healthy growth.Catastrophic coral mortality occurred between 2007 and 2008.The 16S rRNA gene sequencing and PCR amplification,with universally conserved primers,were applied to detect the contagious bacterial community of the microbial mat.The results demonstrated that six bacterial divisions constituted the clone libraries derived from the BBD mat,and that Cyanobacteria are the most diversely represented group that inhabit BBD bacterial mats,despite the fact that species in five others divisions(α-Proteobacteria,γ-Proteobacteria,Bacteroidetes,Verrucomicrobia and Actinobacteria) are also consistently diverse within the BBD mats of diseased coral.Other factors such as coral bleaching,typhoons,ocean acidification and crown-of-thorns starfish outbreaks,are not primarily responsible for the coral mortality within such a short time interval.The disaster expansion of BBD associated with Cyanobacterial blooms is a more likely mechanism impacting these coral reefs.Excessive human activity enhances the eutrophication of the marine water of the reefal region and may result in occurrence of the BBD.  相似文献   
38.
INTRODUCTIONIntheseaareaofNanshaIslands,therearemanyshoalpatchandrapids.Themajorareaisclassifiedas"dangerouszone".Thereforeitisverydifficulttomakeanormalinvestigationonit.Consideringtheremotesensinginformationfeaturesreflectedbythecontrolfunctionoflocalgeographicstructureandthegrowthofcoralisletsandreefs,wefindthatthemostimportantfeatureofthegeographicsystemofNanshaIslandsisthatitsdistributionisregional.Thetrendsurfaceanalysissystembasedontheremotesensingcompositeinformationistoemulatet…  相似文献   
39.
王俊国  刁桂苓 《地震学报》2005,27(2):178-183
千岛岛弧地区属于全球地震活动最为活跃的地区之一. 本文利用哈佛大学测定的千岛岛弧地区地震的矩心矩张量(CMT)解, 分析该地区震源机制的一致性特征, 提出利用震源机制和构造应力场的一致性参数a进行地震预测的思路. 研究结果表明,MWge;7.5地震之前, 都有一致性参数a降低的现象,a的低值起始的时间在发生大震之前的10多天至110多天, a的低值截止的日期距大震在30多天至2天. 相互之间虽然并不完全一致, 但是差别不大. 这种现象的稳定性, 尚需时间的检验, 但是设想在长达数百公里的地区, 连续发生MWge;5.3的地震的震源机制都与构造应力场一致, 应当不是随机的现象, 而是一种具有预测意义的现象. 当积累的震例足够多时, 则有可能确定统一的评判标准和预测准则.   相似文献   
40.
Shallow-water limestones of presumed Late Cretaceous and Eocene age, interbedded with basaltic lavas, were described by earlier authors from São Nicolau in the northwestern part of the Cabo Verde archipelago. If confirmed, these ages would imply late Mesozoic shallow-marine and subaerial volcanic activity in the Cabo Verde archipelago, and document a geological history very different from that known so far from other Cabo Verde Islands, from which no subaerial volcanic activity before the mid-Cenozoic is known. Our re-investigation of the foraminiferal fauna indicates a Late Miocene age for the presumed Late Cretaceous and Eocene limestones. The hypothesis of a long-lived hot spot, active by the Early Cretaceous, and of a major island-building stage in the Cabo Verde Islands during this period, is therefore not supported by the present bio- or chronostratigraphic data.  相似文献   
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