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International Journal of sediment Research 1999年第2期14卷 339-344页

作者： ZHu Zhongli MO Duowen (department of geography, Peking university, China)

Braided river is considered as the main river pattern developed on alluvial fans. But this is not true in Northwest China. Analysis and correlations of the characteristics of more than 10 rivers show that straight river is the main river pattern and braided river only develops on middle segment of the river in this district. The main factor to shape this river pattern on alluvial fans is the standing incision due to changes in precipitation and sedimentary condition caused by climate change since Holocene. Because of the tectonic movement and boundary condition from gravel to loess-like sediment. some rivers have fan-head trenching and others have fan-toe trenching with the u-shaped cross section.

关键词： Alluvial fan River patterns Precipitation and sedimentary condition. Climate changes Boundary condition

INITIATION AND DEVELOPMENT PROCEssEs OF TuNNEL sYsTEMs IN THE HILLY LOEss REGION OF NORTHERN CHINA

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International Journal of sediment Research 2006年第3期21卷 171-179页

作者： T. X. ZHu1 Dr., department of geography, university of Minnesota-Duluth, 10 university Dr., Duluth, MN 55812, u.s.A. department of geography University of Minnesota-Duluth MN 55812 United States

Tunnel systems in the hilly loess region of northern China are among the largest and most complicated in the world. Tunnel formation and development processes were investigated in the Yangdaogou catchment over the period of 1989 through 2002. Newly formed tunnels on the roads in the Wangjiagou watershed were also examined in detail during a single storm in 2002. soil samples were taken from various locations of the tunnel systems in the Yangdaogou catchment for chemical and physical analyses. The controlling factors of tunnel formation are surface drainage conditions and soil materials. Rapid downward mechanical erosion by storm flows seems to be responsible for the original formation of inlets. All tunnels are found in loess and none was found in red Tertiary earth. underground tunnel paths often develop right above an impeding layer, mainly resulting from mechanical erosion rather than chemical dissolution. New inlets develop in old tunnel systems in two major ways. One is roof collapses of an existing tunnel path and the other is the mechanical scouring action of storm flows. A tunnel system can expand upslope or downslope but the associated processes differ. upslope expansion often starts with the formation of one or more inlets resulting from surface washes, followed by the development of an underground tunnel path. Downslope development of a tunnel system is characterized by uneven enlargement of tunnel paths. This study suggests that the key to control of tunnel development is reducing surface water entering a tunnel.

关键词： Piping Tunnel erosion semi-arid areas Gully erosion Loess Plateau

INFLuENCE OF THE ANTARCTIC sEA-ICE ON THE NORTH-WEsT PACIFIC suBTROPICAL HIGH AND ITs BACKGROuND OF OCEANATMOsPHERIC CIRCuLATION

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Chinese science Bulletin 1989年第17期34卷 1463-1465页

作者：彭公炳 PAO K.WANG department of Climatology Institute of Geography Academia Sinica Beijing department of Meteorology University of Wisconsin Madison U. S. A.

In view of the importance of the North-west Pacific subtropical high to weather-climate conditions in large areas of the Chinese territory, we have devoted our attention mainly to analyzing the relationship between the subtropical high and the Antarctic sea-ice. We have found that the high and the sea-ice are closely related to each other in our

关键词： Antarctic sea-ice subtropical high influence model

New findings concerning the Pleistocene Glaciation of the Leh Basin,Ladakh(34°03'N/77°38'E)

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Journal of Mountain science 2010年第4期7卷 367-374页

作者： Hermann Achenbach Geographical Institute University of GoettingenDepartment of High Mountain Geomorphology and Geography

Like for most parts of High Asia,researches concerning the Pleistocene landscape evolution of the Leh Basin(34°03' N/77°38' E) have also left *** push this topic,three up to now unexplored Ladakh Range tributaries of the Leh Basin(stagmo-,Arzu-and Nang-Valley) have been investigated.u-shaped profiles,transfluence passes,moraine mantled and glacially rounded peaks and ridges,roches moutonnées,glacial flank polishings and ground moraines document the former glaciation of the study *** ice fillings of these tributaries reached a minimum thickness up to 540 *** at the valley outlets and on the orographic right side of the Leh Basin,the glaciation was more than 350 m *** on these empirically extracted results,theoretical snow line considerations lead to the conclusion that the whole Leh Basin was filled up by a former Indus-Valley *** ice injection limited to the nourishment areas of the Ladakh Range valleys could not have caused the reconstructed ice cover(down to 3236 m a.s.l.),which is proved by extended ground moraine *** an Indus ice stream network(most likely during the LGP),nourished by inflowing glaciers of the Ladakh-and stok Range,explains the widespread existence of the glacial sediments at the outlets of the investigated valleys.

关键词： Glacial-geomorphology Formerglaciation Last glacial period Equilibrium linealtitude High Asia

ON FORMATION OF TIDAL FRONTs IN COAsTAL sEAs

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Journal of Hydrodynamics 1998年第3期10卷 17-28页

作者： Wang Xiao-huadepartment of geography and Oceanography, university College, Australian Defence ForceAcademy, Canberra ACT 2600, Australia, email :h-wang @ adfa.oz. auM. L. HeronPhysics department, James Cook university Townsville, Q 4811, AustraliaChen WeiThe second Institute of Oceanography, state Oceanic Administration, Hangzhou 310012,P. R. China Australian Defence Force Acad Canberra Australia

An energy equation which includes the effects of potential energy, turbulent dissipation, heat flux and density flux due to fresh water discharge from estuaries is derived to evaluate the formation of frontal structures in coastal seas. Two different forms of tidal mixing criteria emerge which are the h/u3 of simpson and Hunter (1974) for openshallow water and the h/u of Nunes et al (1989) for estuaries. The theory is capable ofpredicting tidal fronts in areas where both surface and lateral input of buoyancy are significant. The theory is applied to a tidal estuary and the locations of haline fronts which result from the influence of the fresh water discharge are predicted. The effect of surface heating on the formation and location of the frontal system is also discussed for the estuary.

关键词： tidal fronts coastal sea

Human-Environment Patterns of Metropolitan spatial Restructuring:Atlanta,Georgia and shanghai,PRC,1950-2000

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世界地理研究 2002年第2期11卷 27-33,87页

作者： susan M. Walcott (department of Anthropology & geography, Georgia state university, Atlanta, GA 30303-3083, u. s.) departmentofAnthropology&geography GeorgiaStateUniversityAtlantaGA30303-3083U.S.

This paper compares the spatial and environmental impacts of rapid growth through the five decades in Atlanta, Georgia and shanghai, PRC. Both metropolitan areas represent the prime demographic and economic engines of their respective regions, and exhibit some of the worst environmental degradation problems, though from significantly different sources. Atlanta epitomizes spatial patterns of sprawl arising from an unfettered topographic and economic setting. shanghai, in a political economy transitioning from decades of centralized constraint, seeks to spread out some of the world’s densest core settlement population to its inner suburbs. Remotely sensed photographic images are utilized to classify land use changes, while census figures and environmental data are integrated in a Geographic Information system to correlate shifts through time.

关键词：亚特兰大州上海市乔治亚州人口-环境模式空间结构调整城市

Discovery and Analysis of the Fossilised Yuling-Man skull

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地域研究与开发 1993年第S1期12卷 8-18页

作者： Feng Xingxiang Zhou Huashan Ba Zhigang Zhang Guangye Wang Panji Zhang Zhenyu(department of geography, Henan university Kaifeng, Henan 475001, China)

A fossilised paleoanthropological skull was discovered in November 1987, in the guily-head cliff on the east bank of Wenyu River near Xinza village, Yuling - town (hence the name Yuling-Man), Lingbao country, Henan Province, China. The skull, dated to an absolute u-isotope (u234 to u238 ) age of B. P. 156000 ± 13000 years, was found in the upper portion of the alluvial statum of the mid-Pleistocens series, together with pateoliths of the Kehe Cutture system in the mid-late Paleolithic Periods. Although much research has been nomied out in this area, this is the first fossilised paleoanthropological skull in have been found. Therefore, this project, funded by the Natural science Foundation/Henan scientific Committee, is making new contributions to paleoanthropological research in China.

关键词： Yuling-Man late mid-Pleistocene Paleolithic Period.

CHINA: A COuNTRY OF THE THIRD WORLD OR THE THIRD GREAT POWER?

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Journal of Geographical sciences 1996年第3期6卷 84-88页

作者： Hu Zhaoliang(department of geography, Peking university, Beijing 100871People’s Republic of China)soon-Cheol Moonseoul National university, seoul, Korea

In 1990, World Bank and IMF calculated China's GDP with Purchasing Power Parity (PPP). World Bank estimated it at 1,950 u.s dollars and IMF did it at 1,300. According to this figure, China ranked next to u.s. and Japan in the world. This result has created a dispute whether China is a country of the Third World or the third great power. For explaining this question, measuring system of the PPP and traditional exchange rate must be exanined first.

关键词： third world economic growth GDP China

Multifractal modelling and spectrum analysis: Methods and applications to gamma ray spectrometer data from southwestern Nova scotia, Canada

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science China Earth sciences 2006年第3期49卷 283-294页

作者： CHENG Qiuming1,2 1. state Key Lab of Geological Processes and Mineral Resources, China university of Geosciences, Wuhan 430074, China 2. department of Earth and space science and Engineering, department of geography, York university, 4700 Keele street, Toronto, Ontario, M3J 1P3, Canada 1. state Key Lab of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 2. department of Earth and space science and Engineering Department of Geography York University 4700 Keele Street Toronto Ontario M3J 1P3 Canada

Multifractal spectrum, autocorrelation/semivariogram and power spectrum are three dif- ferent functions characterizing a field or measure from different aspects. These functions are interre- lated in such that the autocorrelation/semivariogram and power spectrum are related to the low order statistical moments (0 to 2 nd) which may determine the local multifractality (τ ″(1)) of a multifractal measure. A better understanding of the interrelationships among these three functions is important because, on one hand, the multifractal modelling characterizes a multifractal measure in a more de- tailed manner since it involves moments of all orders. On the other hand, the commonly used semivariogram and power spectrum functions can be used as alternatives to study the dominant mul- tifractal properties around the mean measure. Moreover, semivariogram and power-spectrum func- tions provide spatial and spectral information, which is highly valued in geological applications. A new fractal relation found between area and power-spectrum will be useful for investigation of new meth- ods of spatial-spectral analysis for pattern recognition, anomaly separation, classification, etc. These results have been demonstrated with the case study of modelling gamma ray spectrometer data from the mineral district, southwestern Nova scotia, Canada. The results have shown that the values of uranium (u), thorium (Th) and potassium (K) may possess monofractal properties whereas the ratios of these values show high multifractality. The values of the ratios u/K and u/Th show relatively large variances and may provide more information for distinguishing the distinct phases of the granites, country rocks as well as possible gold mineralization-associated regional hydrothermal alteration zones. In addition, the power spectra for u, Th, K, u/Th and u/K consistently show two distinct power-law relationships for two ranges of wave number 12≤ω ≤160 km and 0≤ω ≤12 km. These properties might provide usefu

关键词： gamma ray spectrometer data, gold mineralization, alteration zones, multifractal modelling, spectral analysis, GIs.