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101.
INTRODUCTIONTheSubeiShoalandtheChangjiangRiverestuarineareainthewestoftheHuanghaiandEastChinaSeasisoneofthemarginalseasintheworld ,wheresuspendedmatterisextremelyhigh .Here ,notonlyistheretheTaiwanWarmCurrentoneoftheKuroshio’sbranchesintheEastChinaSea,butalsotheHuanghaiCoastalCurrent,andChangjiangDilutedWater.Sothestrongmixingbetweenthecoastalandoffshorewaterscomplicatessuspendedmatterdistributioninthisarea.HowthesuspendedmatterdischargedfromtheChangjiangRiverandtheabandonedHuan…  相似文献   
102.
The Changjiang River (Yangtze) is one of the fastest growth areas of container transportation in Chi-na. Rail, road and water transportation have competed against each other for container transportation in the Chang-jiang River main line and its delta area. It is of significance to assess these different transportation modes scientifi-cally in order to organize container transportation efficiently in this area and make decision for integral plan and construction of transportation system in this area. This paper outlines application of fuzzy comprehensive evaluation to appraise different modes of typical direction of containers. Twelve assessment indexes were decided. Membership functions were formulated. Evaluation results indicated that road transportation was optimal mode in the Changjiang River delta area, however water transportation was the primary way in the Changjiang River main line.  相似文献   
103.
Armoured jawless fish, or 'ostracoderms', lived 450–360 million years ago, and display unusual morphologies, unlike any modern fish group. Since they left no living descendants, their mode of swimming has, until recently, remained speculative, although this is a crucial question as the first true pectoral fins evolved within the 'ostracoderms'. The discovery of the oldest-known fish trails, from the Early Devonian (400 million year old) 'Lower Old Red Sandstone' of south-east Wales offers new insights into the swimming behaviour of these early fish, notably the osteostracan 'ostracoderms' (or cephalaspids), whose horseshoe-shaped head and paddle-shaped pectoral fins have remained a functional riddle.  相似文献   
104.
Urban heat environmental quality(UHEQ) is affected by the interacting of weather condition and underlying surface framework of urban area .In the last two decades,many researchers from domestic and overseas have studied many problems at the aspect of urban heat environment such as urban heat islands ,urban air temperature and their rela-tion with urban land cover,city population,air pollution etc,In the recent years,Hangzhou,acting as a center city of Zhejiang Province in China,its urbanization quantum and quantity have both changed greatly,in particular ,representing as business affairs building,resident real property and all kins of specialty market having arisen in built-up zone,Based on Landsat TM images data in 1991 and 1999,urban underlying surface temperature value and Normalized Difference Vegetation Index (NDVI) were calculated using image interpreting and supervised classification technique by remote sensing software ERDAS image 8.4,The relation model between urban underlying surface temperature (UUST )and urban air temperature was setup according to the certain correlation patten .Reference to the relational standard of assessing human comfort and other meteorology data of Hangzhou City in summer,the spatial distribution characteristic and the spatial varia-tion degree of human comfort of heat environmental quality are estimated and mapped on a middle scale,that is ,in six districts of Hangzhou City .Then the paper reveals the main characteristic of spatial variation from 1991 to 1999.Lastly,the change mechanism is analyzed and discussed from the viewpoint of city planning,construction and environmental protec-tion.  相似文献   
105.
Abstract— The size, shape, composition, and vesicle content of 6 kg of layered tektite fragments, excavated near the town of Huai Sai, Thailand, place some constraints on the formation of layered tektites. The mass, shape, and distribution of the fragments are not consistent with an origin as a “puddle” of impact melt but suggest that they were derived from a single equant block. The presence of vesicles up to 7 mm in mean diameter within the tektite fragments suggests that the material was too viscous to allow for significant gravity-driven flow. These results suggest that layered tektites may be analogous to lava bombs, which may have been stretched and deformed in flight but underwent little flow after landing. Rather than being a product of “unusual circumstances,” such as multiple impacts, layered tektites may differ from splash-form tektites only in initial temperature of formation, speed of ejection, and small differences in initial composition.  相似文献   
106.
Using a set of compilations of measurements for extragalactic radio sources, we construct all-sky maps of the Faraday rotation produced by the Galactic magnetic field. In order to generate the maps, we treat the radio source positions as a kind of 'mask' and construct combinations of spherical harmonic modes that are orthogonal on the masked sky. As long as relatively small multipoles are used, the resulting maps are quite stable to changes in the selection criteria for the sources, and show clearly the structure of the local Galactic magnetic field. We also suggest the use of these maps as templates for cosmic microwave background (CMB) foreground analysis, illustrating the idea with a cross-correlation analysis between the Wilkinson Microwave Anisotropy Probe ( WMAP ) data and our maps. We find a significant cross-correlation, indicating the presence of a significant residual contamination.  相似文献   
107.
Attractabilities of different diets and dietary selectivity of Chinese shrimp, Fenneropenaeus chinensis were studied through behavior observation and feeding experiment, respectively. The five diets used in the experiment are: Fish Flesh (FF), Shrimp Flesh (SF), Clam Foot (CF), Polychaete Worm (PW), and Formulated Diet (FD). No significant differences of attractability exist between any two different diets when every two natural diets or all five diets are provided simultaneously. On the other hand, significant differences of attractability exist between FD and every single natural diet when they are provided simultaneously. Results of behavioral observation indicate that natural diets are more attractive than FD. In feeding experiment, Chinese shrimp has distinct selectivity on different diets. It positively selects CF and PW, negatively selects FF and SF, and excludes FD absolutely. The results of the present studies indicate that the dietary selectivity of shrimp was based not only on the attractabilities of the diets, but also on the responses such as growth and food conversion.  相似文献   
108.
Reviews     
OFFICE DEVELOPMENT: A Geographical Analysis by M. Bateman. 14 × 22 cm, xvi and 175 pages. Croom Helm: London 1985 (ISBN 0 7099 0697 8) $A35.95 (cloth).

ATLAS OF YOUTH UNEMPLOYMENT, 1981: The Geographic Distribution of Youth Unemployment in Australian Cities from the 1981 Census According to Birthplace and Gender by P. Matwijiw with E. Bamford and C. Maher. 21 × 29 cm, 127 pages. Australian Institute of Multicultural Affairs: Melbourne 1985 (ISBN 949890 33 2) $A12.00 (limp).

ENVIRONMENT AND HEALTH by A. J. Rowland and P. Cooper. 23 × 16 cm, vi and 205 pages. Edward Arnold: London 1983 (ISBN 0 7131 2855 0) $A27.95 (limp).

FAMINE AS A GEOGRAPHICAL PHENOMENON edited by B. Currey and G. Hugo. 17 × 24 cm, vi and 202 pages. Reidel: Dordrecht 1984 (ISBN 90 277 1762 1) Dfl 95.00, $US37.00 (cloth).

SOUTH AUSTRALIA'S CHANGING POPULATION (South Australian Geographical Papers No. 1) by G. J. Hugo. 25 × 18 cm, 71 pages. Royal Geographical Society of Australasia (SA Branch): Adelaide 1983 (ISBN 0 909112 05 03) $A4.00 (limp).

DEVELOPMENTS IN POLITICAL GEOGRAPHY edited by M. A. Busteed. 23 × 15 cm, 340 pages. Academic Press: London 1983 (ISBN 0 12 148420 3) $US42.00 (cloth).

NEITHER JUSTICE NOR REASON: A Legal and Anthropological Analysis of Aboriginal Land Rights by M. Gumbert. 22 × 14 cm, xv and 215 pages. University of Queensland Press: St Lucia 1984 (ISBN 0 7022 1746 8) $A20.00 (cloth).

RURAL RESOURCE MANAGEMENT by P. J. Cloke and C. C. Park. 14 × 22 cm, xiii and 473 pages. Croom Helm: London 1985 (ISBN 0 7099 2037 7) $A44.95 (cloth).

FARM POLICY IN AUSTRALIA by R. K. Hefford. 14 × 22 cm, xviii and 415 pages. University of Queensland Press: St Lucia 1985 (ISBN 0 7022 1698 4) $A40.00 (cloth).

TRANSPORT AND COMMUNICATIONS FOR PACIFIC MICROSTATES: Issues in Organisation and Management edited by C. C. Kissling. 14 × 21 cm, 192 pages. Institute of Pacific Studies, University of the South Pacific: Suva 1984. $A10.00 (cloth), $A8.00 (limp).

TIMES OF CRISIS: Epidemics in Sydney 1788–1900 by P. H. Curson. 15 × 25 cm, xii and 195 pages. Sydney University Press: Sydney 1985 (ISBN 0 424 00112 8). $A35.00 (cloth).

PEASANTS, SUBSISTENCE, ECOLOGY AND DEVELOPMENT IN THE HIGHLANDS OF PAPUA NEW GUINEA by L. S. Grossman. 24 × 16 cm, xxi and 302 pages. Princeton University Press: Princeton, NJ 1984 (ISBN 0 691 09406 3) $US45.50.

THE WORLD FOOD PROBLEM 1950–1980 by D. Grigg. 15 × 24 cm, 276 pages. Basil Blackwell: Oxford 1985 (ISBN 0 631 13481 6) $A58.50 (cloth).

POPULATION REDISTRIBUTION AND DEVELOPMENT IN SOUTH ASIA edited by L. A. Kosinski and K. M. Elahi. 17 × 24 cm, 243 pages. Reichel: Dordrecht 1985 (ISBN 90 277 1938 1) Dfl 120.00, $US44.00, £30.50 (cloth).

GEOGRAPHY AND ETHNIC PLURALISM edited by C. Clarke, D. Ley and C. Peach. 15 × 23 cm, xvii and 294 pages. Allen & Unwin: London 1984 (ISBN 0 04 309107 5) $A45.00 (cloth); (ISBN 0 04 309108 3) $A24.95 (limp).

SOCIAL GEOGRAPHY IN INTERNATIONAL PERSPECTIVE edited by J. Eyles. 14 × 22 cm, 295 pages. Croom Helm: London 1986 (ISBN 0 7099 0944 6) $A49.95 (cloth).

THE GENTRIFICATION OF INNER MELBOURNE: A Political Geography of Inner City Housing by W. S. Logan. 14 × 22 cm, xvi and 328 pages. University of Queensland Press: St. Lucia 1985 (ISBN 0 7022 1729 8) $A50.00 (cloth).

YELLOWCAKE AND CROCODILES: Town Planning, Government and Society in Northern Australia by J. Lea and R. Zehner. 14 × 22 cm, xxvi and 200 pages. Allen & Unwin: Sydney 1986 (ISBN 0 86861 875 6) $A24.95 (cloth); (ISBN 0 86861 843 8) $A 14.95 (limp).

THE BUNGALOW: The Production of a Global Culture by A. D. King. 20 × 25 cm, xii and 310 pages. Routledge & Kegan Paul: London 1984 (ISBN 0 7100 9538 4) $A62.50 (cloth).

THE WEST EUROPEAN CITY: A Social Geography by P. White. 15 × 23 cm, xviii and 269 pages. Longman: London 1984 (ISBN 0 582 30047 9) $A22.95 (limp).

THE SHAPING OF AMERICA: A Geographical Perspective on 500 years of History. Volume 1. Atlantic America, 1492–1800 by D. W. Meinig. 18 × 25 cm, xii and 500 pages. Yale University Press: New Haven 1986 (ISBN 0 300 03548 9) $US35.00 (cloth).

CANBERRA: MYTHS AND MODELS. Forces at Work in the Formation of the Australian Capital by K. F. Fischer. 21 × 30 cm, 166 pages. Institute of Asian Studies: Hamburg 1984 (ISBN 3 88910 009 0).

THE GEOGRAPHY OF PEACE AND WAR edited by D. Pepper and A. Jenkins. 15 × 23 cm, vi and 222 pages. Basil Blackwell: Oxford 1985 (ISBN 0 631 13559 6) $A75.00 (cloth); (ISBN 0 631 14069 7) $A23.95 (limp).

POLITICAL GEOGRAPHY: World‐economy, Nation‐state and Locality by P. J. Taylor. 15 × 23 cm, × and 238 pages. Longman: London 1985 (ISBN 0 582 30088 6) $A24.95 (limp).

THE INDUSTRIAL GEOGRAPHY OF CANADA by A. Blackbourn and R. G. Putnam 14 × 22 cm, 201 pages. Croom Helm: London 1984 (ISBN 0 7099 0622 6) $A42.50 (cloth).

THE FOODMAKERS by S. Sargent. 13 × 20 cm, 296 pages. Penguin: Ringwood 1985 (ISBN 0 14 007359 0) $A8.95 (limp).

LIMITS TO PREDICTION edited by R. B. McKern and G. C. Lowenthal. 13 × 19 cm, xiii and 163 pages. Australian Professional Publications: Sydney 1985 (ISBN 0 949416 029) $A14.95 (limp).

THE KANGAROO KEEPERS edited by H. J. Lavery. 18 × 25 cm, xxvi and 211 pages. University of Queensland Press: St Lucia 1985 (ISBN 0 7022 1875 8).

PRACTICAL ECOLOGY by D. D. Gilbertson, M. Kent and F. B. Pyatt. 15 × 23 cm, 320 pages, Hutchinson: London 1985 (ISBN 0 09 162651 X) £8.95.

BASIC BIOGEOGRAPHY (Second edition) by N. Pears. 15 × 24 cm, × and 358 pages. Longman: London 1985 (ISBN 0 582 30120 3) $A24.95 (limp).

ENVIRONMENTAL CHANGE (Second edition) by A. Goudie. 23 × 15 cm, xi and 258 pages. Oxford University Press: Oxford 1983 (ISBN 0 19 874135 9) A16.00 (limp).

MEGA‐GEOMORPHOLOGY edited by R. Gardner and H. Scoging. 16 × 24 cm, xiii and 240 pages. Oxford University Press: Oxford (ISBN 0 19 823244 6) $A48.00.

GRANITE LANDFORMS by C. R. Twidale. 25 × 17 cm, xxiii and 372 pages. Elsevier: Amsterdam 1982 (ISBN 0 444 42116 5) $A148.25.  相似文献   

109.
The Granny Smith (37 t Au production) and Wallaby deposits (38 t out of a 180 t Au resource) are located northeast of Kalgoorlie, in 2.7 Ga greenstones of the Eastern Goldfields Province, the youngest orogenic belt of the Yilgarn craton, Western Australia. At Granny Smith, a zoned monzodiorite–granodiorite stock, dated by a concordant titanite–zircon U–Pb age of 2,665 ± 3 Ma, cuts across east-dipping thrust faults. The stock is fractured but not displaced and sets a minimum age for large-scale (1 km) thrust faulting (D2), regional folding (D1), and dynamothermal metamorphism in the mining district. The local gold–pyrite mineralization, controlled by fractured fault zones, is younger than 2,665 ± 3 Ma. In augite–hornblende monzodiorite, alteration progressed from a hematite-stained alkali feldspar–quartz–calcite assemblage and quartz–molybdenite–pyrite veins to a late reduced sericite–dolomite–albite assemblage. Gold-related monazite and xenotime define a U–Pb age of 2,660 ± 5 Ma, and molybdenite from veins a Re–Os isochron age of 2,661 ± 6 Ma, indicating that mineralization took place shortly after the emplacement of the main stock, perhaps coincident with the intrusion of late alkali granite dikes. At Wallaby, a NE-trending swarm of porphyry dikes comprising augite monzonite, monzodiorite, and minor kersantite intrudes folded and thrust-faulted molasse. The conglomerate and the dikes are overprinted by barren (<0.01 g/t Au) anhydrite-bearing epidote–actinolite–calcite skarn, forming a 600-m-wide and >1,600-m-long replacement pipe, which is intruded by a younger ring dike of syenite porphyry pervasively altered to muscovite + calcite + pyrite. Skarn and syenite are cut by pink biotite–calcite veins, containing magnetite + pyrite and subeconomic gold–silver mineralization (Au/Ag = 0.2). The veins are associated with red biotite–sericite–calcite–albite alteration in adjacent monzonite dikes. Structural relations and the concordant titanite U–Pb age of the skarn constrain intrusion-related mineralization to 2,662 ± 3 Ma. The main-stage gold–pyrite ore (Au/Ag >10) forms hematite-stained sericite–dolomite–albite lodes in stacked D2 reverse faults, which offset skarn, syenite, and the biotite–calcite veins by up to 25 m. The molybdenite Re–Os age (2,661 ± 10 Ma) of the ore suggests a genetic link to intrusive activity but is in apparent conflict with a monazite–xenotime U–Pb age (2,651 ± 6 Ma), which differs from that of the skarn at the 95% confidence level. The time relationships at both gold deposits are inconsistent with orogenic models invoking a principal role for metamorphic fluids released during the main phase of compression in the fold belt. Instead, mineralization is related in space and time to late-orogenic, magnetite-series, high-Mg monzodiorite–syenite intrusions of mantle origin, characterized by Mg/(Mg + FeTOTAL) = 0.31–0.57, high Cr (34–96 ppm), Ni (22–63 ppm), Ba (1,056–2,321 ppm), Sr (1,268–2,457 ppm), Th (15–36 ppm), and rare earth elements (total REE: 343–523 ppm). At Wallaby, shared Ca–K–CO2 metasomatism and Th-REE enrichment (in allanite) link Au–Ag mineralization in biotite–calcite veins to the formation of the giant epidote skarn, implicating a Th + REE-rich syenite pluton at depth as the source of the oxidized hydrothermal fluid. At Granny Smith, lead isotope data and the Rb–Th–U signature of early hematite-bearing wall-rock alteration point to fluid released by the source pluton of the differentiated alkali granite dikes.  相似文献   
110.
The 40Ar/39Ar geochronological method was applied to date magmatic and hydrothermal alteration events in the Mantos Blancos mining district in the Coastal Cordillera of northern Chile, allowing the distinction of two separate mineralization events. The Late Jurassic Mantos Blancos orebody, hosted in Jurassic volcanic rocks, is a magmatic-hydrothermal breccia-style Cu deposit. Two superimposed mineralization events have been recently proposed. The first event is accompanied by a phyllic hydrothermal alteration affecting a rhyolitic dome. The second mineralization event is related to the intrusion of bimodal stocks and sills inside the deposit. Because of the superposition of several magmatic and hydrothermal events, the obtained 40Ar/39Ar age data are complex; however, with a careful interpretation of the age spectra, it is possible to detect complex histories of successive emplacement, alteration, mineralization, and thermal resetting. The extrusion of Jurassic basic to intermediate volcanic rocks of the La Negra Formation is dated at 156.3 ± 1.4 Ma (2σ) using plagioclase from an andesitic lava flow. The first mineralization event and associated phyllic alteration affecting the rhyolitic dome occurred around 155–156 Ma. A younger bimodal intrusive event, supposed to be equivalent to the bimodal stock and sill system inside the deposit, is probably responsible for the second mineralization event dated at ca. 142 Ma. Other low-temperature alteration events have been dated on sericitized plagioclase at ca. 145–146, 125, and 101 Ma. This is the first time that two distinct mineralization events have been documented from radiometric data for a copper deposit in the metallogenic belt of the Coastal Cordillera of northern Chile. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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