饶阳凹陷古近系沙河街组层序地层分析及沉积体系研究

利用地震、测井、岩心等资料,对该区进行层序地层学的分析和研究,在层序地层单元划分和对比的基础上,将饶阳凹陷古近系沙河街组划分出6个三级层序,并对每个层序的主控成因进行了详细的研究,总结出各层序的不同特点。同时对每个层序内部的沉积特点和沉积体系进行了分析,指出了层序发育对沉积体系的控制作用。研究过程中,还对层序不同体系域的油气藏类型和油气聚集规律进行了研究,并指出了各体系域可能发育的最有利的油气藏类型。     

Monitoring of protected bands of Terkos drinking water reservoir of metropolitan Istanbul near the Black Sea coast using satellite data

In this study, remote sensing (RS) with computer-based geographic information systems (GIS) techniques are used as a tool for monitoring the water basin area and water quality in Istanbul's relatively less polluted and comparatively less destroyed catchment of the metropolis drinking water dam reservoir named Terkos. It is necessary to work with recent data to be able to identify the effects of urbanization on the water quality of the Terkos dam catchment area that supplies drinking water to the metropolis. RS is an important tool to monitor water quality and urban terrain. For this aim, a project has been initiated at the Technical University Remote Sensing Laboratory, under the Istanbul Water and Sewerage Administration (ISKI) sponsorship in Istanbul. The project uses SPOT-PAN, XS and IRS-1C/D PAN and satellite data of 1993 and 2000 for urban analysis and Landsat-TM and LISS-III satellite data of 1992 and 2000 for water quality. For calibration and validation, ground truth samples are collected from the experimental area. The RS data was converted into the UTM coordinate system and image enhancement and classification techniques are used. Raster data is converted to vector data to assess the study area for analyzing in GIS for the purpose of planning and decision-making on protected water basin zones. As a result of monitoring land use and water quality changes, recommendations are made for planning and management of the protected environment of the Terkos catchment protected area. Measuring land use change is a very important issue for controlling the future development of the basin, GIS techniques are performed and results are illustrated in established models on the four protected zones of Terkos water basin.     

A comparison of drainage networks derived from digital elevation models at two scales

Automated generation of drainage networks has become increasingly popular with powerful analytical functions in geographic information systems (GIS) and with the increased availability of digital elevation models (DEMs). This paper compares drainage networks derived from DEMs at two scales, 1:250 000 (250K) and 1:24 000 (24K), using various drainage parameters common in hydrology and geomorphology. The comparison of parameters derived from the 250K DEMs with those from the 24K DEMs in 20 basins ranging from 150 to 1000 km² in West Virginia shows that the goodness-of-fit between parameter estimates based on the DEMs varies. Results clearly show that superior estimations are produced from the 24K DEMs. Better estimates can be obtained from the 250K DEMs for stream length and frequency parameters than for gradient parameters. However, the estimation of the mean gradient parameters based on the 250K DEMs seems to improve with increasing terrain complexity. Finally, basin size does not strongly affect the accuracy of parameter estimates based on the 250K DEMs.     

Method of characteristics in spherical geometry applied to a Harang-discontinuity situation

The method of characteristics for obtaining spatial distributions of ionospheric electrodynamic parameters from ground-based spatial observations of the ground magnetic disturbance and the ionospheric electric field is presented in spherical geometry. The method includes tools for separation of the external magnetic disturbance, its continuation to the ionosphere, and calculation of ionospheric equivalent currents. Based on these and the measured electric field distribution, the ionospheric Hall conductance is calculated as the primary output of the method. By estimating the Hall- to-Pedersen conductance ratio distribution, the remaining ionospheric electrodynamic parameters are inferred. The method does not assume = 0 to allow to study time-dependent situations. The application of this method to a Harang discontinuity (HD) situation on 27 October 1977, 17:39 UT, reveals the following: (1) The conductances at and north of the HD are clearly reduced as compared to the eastern electrojet region. (2) Plasma flow across the HD is observed, but almost all horizontal current is diverted into upward-flowing field-aligned currents (FACs) there. (3) The FACs connected to the Hall currents form a latitudinally aligned sheet with a magnitude peak between the electrically and magnetically defined HD, where break-up arcs are often observed. Their magnitude is larger than that of the more uniformly distributed FACs connected to the Pedersen currents. They also cause the southward shift of the magnetically defined HD with respect to the electrically defined one. (4) A tilt of the HD with respect to geomagnetic latitude as proposed by an earlier study on the same event, which used composite vector plot technique, and by statistical studies, is not observed in our single time-step analysis.Also at: Finnish Meteorological Institute, Geophysical Research, P.O. Box 503, FIN-00101 Helsinki, Finland.     

桐柏—大别山掀斜隆升对长江中游环境的影响

桐柏－大别山自早更新世晚期以来,不断发生着自北向南的掀斜隆升,从而对长江中游的环境,尤其是水系的演化产生了严重影响。主要表现在：鄂西各东西向河流的阶地高差自北向南逐渐降低;江汉平原水系同步向南发生异常弯曲,长江主河道不断南移,湖相沉积范围也由北向南收缩和迁移;鄂东长江两岸水系和河谷地貌发育不对称,长江主河道紧逼南岸丘陵区。现代地壳形变资料表明：桐柏－大别山的掀升作用仍在继续,由此引起的环境问题还将     

非线性地球化学动力学

非线性地球化学动力学的研究主要包括五个方面：①地球化学非线性反应动力学;②矿物沉淀、结晶与生长的非线性动力学;③流体流动－反应耦合的非线性动力学;④力学－化学耦合的非线性动力学;⑤地球化学循环的非线性动力学或非线性全球动力学。分别总结了上述五个方面的研究进展,讨论了地球化学非线性动力学研究中存在的问题和今后的发展方向。     

Geopolitical codes and popular representations*

Geopolitical codes – intellectual tools for practising statecraft – share a certain basic understanding of the world with less articulate, popular representations. Both are influenced by national geographies and histories. The international power game may (particularly in large countries) temporarily alienate codes from popular representations but the ensuing conflicts also prove the solidity of popular visions about the world order. Change is nevertheless possible and should be one of the central themes of research in geopolitical representations. This article concludes with specifying five perspectives that can be adopted in cross-national research: time/space models of the world, national myths, territorial narratives, active/passive approach of international relations and reactions to international crises.     

“05.6”华南致洪暴雨过程中各尺度天气系统的作用

利用MICAPS、NCEP的grib 1x1°、MM5V37模式运行输出等资料,通过天气形势和物理量诊断分析的方法,对造成"05.6"华南致洪暴雨各尺度天气系统进行综合分析。结果表明:该次暴雨过程是在副热带高压、南亚高压、高空槽等大尺度天气系统有利配置的环流形势下,低涡、切变线、静止锋、西南暖低压等天气尺度及中小尺度系统得到发展,各尺度天气系统相互作用下产生的。暴雨落区位于高空槽前、南亚高压脊线反气旋曲率最大处、中低层低涡切变的东南侧和地面静止锋附近。高低空急流相互耦合在这次暴雨的发生过程中起到了关键的作用,高低空急流轴之间的区域是高空辐散区与低空辐合区相配合区域,是强暴雨落区。     

国家创新系统研究中地理学的视角*

促进知识经济发展的关键是建立和完善国家创新系统,而创新系统中知识流动的效率是解释国家创新能力高低最重要的指标。高新技术企业和知识的生产和传播者在空间上的集聚现象说明知识的流动是一个空间过程。从创新系统的区域层次性、知识流动的区位效应以及知识创新的区域分工等现象中,可以看到从地理学角度研究国家创新系统的切入点。     

Griffith Taylor and the SE Australian highlands: issues of data sources and testability in interpretations of long‐term drainage history and landscape evolution

Much of the current research on long‐term landscape evolution and drainage history in SE Australia is built in one way or another on the early work of Griffith Taylor. The controversy prompted by several attempts to incorporate Taylor's work in recent plate tectonics interpretations of the long‐term evolution of SE Australia highlights differences of opinion as to the appropriate methodologies for such investigations. These questions, including the issues of data sources in reconstructions of long‐term landscape history, testability of such reconstructions, and the relationship between the landscape history so reconstructed and larger‐scale, regional landscape histories, appear not to have been addressed in recent literature on geomorphological methodology. This literature notes the demise of critical rationalism and appears to espouse a strongly relativist viewpoint, which relies on the shared understanding among the discipline's practitioners as to what are appropriate data sources and tests for hypotheses of long‐term landscape evolution. This offers little hope for resolution of the current disputes about the evolution of the drainage systems of SE Australia, but puts the onus squarely on us, the practitioners, to develop shared understandings of the appropriate data sources and tests for our hypotheses and grand schemes of the type so favoured by Griffith Taylor.