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1.
This work derives algebraic expressions for Airy-type isostatic equilibrium and disequilibrium of lithospheric blocks within asthenosphere, considering a more realistic case of continuously varying densities of the lithosphere along mutually perpendicular directions. Isostatic (dis)equilibrium must be linked to the porosity and density of the rock matrix, and to pore fluid density since these factors govern the bulk density of wet sediments/porous rocks. Two combinations of exponential and linear increase of density with depth are demonstrated. Isostatic disequilibrium would speed up sinking/uplift of the lithospheric blocks. Given any other (empirical) equations for density variation in three perpendicular directions, isostatic (dis)equilibrium such as Eqs. 14, 17, 18, 28, and 29 can be theorized as well.  相似文献   

2.
This article uses the case of anti-eviction politics to examine the urban land question. Following the ideas and practices of the Chicago Anti-Eviction Campaign and its global interconnections, it traces the potentialities and limits of poor people’s movements as they battle displacement and enact a politics of emplacement. In doing so, it seeks to expand existing understandings of dispossession. Drawing on critical race studies and postcolonial theory, the article pays attention to the relationship between property and personhood in the context of long histories of racial exclusion and colonial domination. It asks: what politics of home and land is possible outside the grid of secure possession and sovereign self? The work of the Chicago Anti-Eviction Campaign points to how various modes of collectivism can be asserted through practices of occupation as well as through global frameworks of human rights. Challenging the secure categories of property and personhood through which liberalism is constituted, such politics is attuned to the present history of racial banishment but is also subject to aspirations of resolution and possession.  相似文献   

3.
Identifying China’s leading world city: a network approach   总被引:3,自引:0,他引:3  
This paper reports our research on China’s world cities. Formal network analysis of air passenger linkages for recent years among China’s most populous cities and among many of the world’s largest cities allows us to identify the country’s leading world city from among the leading Mainland candidates, Beijing, Shanghai and Guangzhou. We theorize our findings about China’s world cities in relation to both global forces (and China’s increasing entanglement with them) and the policies and actions of the national state. We examine the national and global urban network through a longitudinal, two-level analysis of airline passenger travel for four time points between about 1990 and 2005. We show that Beijing was China’s leading world city at the beginning of the time period, a status it lost nationally in as early as 1995, and then globally 10 years later. On the other hand Shanghai became China’s leading world city, and it acquired this status first nationally in 2000, and then globally in 2005. The changing status of the Chinese capital corresponds to the country’s increasing involvement with the capitalist world economy. Shanghai’s ascendance as the leading world city in China may indicate that global forces have come to play an increasingly important role relative to that of the developmental state.
Michael F. TimberlakeEmail:
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4.
We consider the problem about determination of characteristics of a lava flow from the physical parameters measured on its surface. The problem is formulated as an inverse boundary problem for the model simulating the dynamics of a viscous heat-conducting incompressible inhomogeneous fluid, where, on the basis of additional data at one part of the model boundary, the missing conditions at another part of the boundary have to be determined, and then the characteristics of fluid in the entire model domain have to be reconstructed. The considered problem is ill-posed. We develop a numerical approach to the solution of the problem in the case of a steady-state flow. Assuming that the temperature and the heat flow are known at the upper surface of the lava, we determine the flow characteristics inside the lava. We compute model examples and show that the lava temperature and flow velocity can be determined with a high precision when the initial data are smooth or slightly noisy.  相似文献   

5.
A technique is suggested and the thermal thickness of the lithosphere is calculated, as well as the temperature distribution in the lithosphere on the basis of data on topography, the age of the oceanic bottom, crustal composition and structure, gravity anomalies, and mean annual surface temperatures. The bottom of the lithosphere is determined as the 1300°C isotherm. The calculation resolution is 0.5°×0.5°. All first-order tectonic structures, such as mid-ocean ridges and plume areas in oceans, continental rifts, cratons, and orogenic belts, are expressed in the computed thermal thickness. The comparative analysis of the thermal thickness of oceanic and continental lithosphere, lithosphere of cratons and young platforms, ancient and young orogens, remnant oceanic basins and adjacent continental areas can be used in geodynamical analysis of the corresponding regions.  相似文献   

6.
Shujuan Li  Daniel Sui 《GeoJournal》2013,78(4):615-626
While Pareto’s law has been widely supported by empirical evidence in urban studies, past studies have focused on finding best fits for city rank-size distribution. A main concern with Pareto’s law is the truncation of sample selection, for which few studies have examined it directly. This study tests three existing threshold methods (number threshold, size threshold, and urban population percentage threshold) using China’s city system as a case study. In addition, this study proposes a new method based upon the percentage threshold of the total number of cities. A systematic analysis is applied to examine the relationship between Pareto exponent and sample size using different threshold methods. The results show that Pareto exponent is sensitive to sample size and the truncation point. Including only large cities is problematic because a slight change in the truncation point will yield quite different results of Pareto exponent. In addition, the new method, the percentage threshold of the total number of cities method, presents an advantage over previous methods, in that this method yields a consistent set of results over a wide range of thresholds. Finally, when using this new method with China’s city system, the Pareto exponent presents a turning point in 1996, representing China’s transition from a planned economy to a more market oriented economy during that period.  相似文献   

7.
This paper examines changes in gender relations in a small coastal community as a result of the 2010 Chile earthquake and tsunami. Vulnerability and resilience are used as a conceptual framework to analyse these changes. Based on empirical evidence from a seven-year longitudinal study and quasi-ethnographic work, we explore changes in power relations at the different stages of the disaster and longer-term recovery as well as the conditions that fostered these changes. Our findings show distinct patterns of change. First, disasters can trigger long-lasting changes that challenge historical patriarchal relations. Second, while vulnerability increases following a disaster, resilience can potentially counteract women’s vulnerability. We propose that resilience can be a pathway to produce long-term changes in gender relations and empower women in the context of disasters.  相似文献   

8.
This is a snapshot of the today’s views of the Earth with its geospheres, and terrestrial and extraterrestrial triggers of its dynamics and energy sources. Along with the presented brief historic outline of the planetary evolution, these data can make basis for creating in the future a truly global model of the Earth’s dynamics and evolution.  相似文献   

9.
The Ketzin pilot site, led by the GFZ German Research Centre for Geosciences, is Europe??s longest-operating on-shore CO2 storage site with the aim of increasing the understanding of geological storage of CO2 in saline aquifers. Located near Berlin, the Ketzin pilot site is an in situ laboratory for CO2 storage in an anticlinal structure in the Northeast German Basin. Starting research within the framework of the EU project CO2SINK in 2004, Ketzin is Germany??s first CO2 storage site and fully in use since the injection began in June 2008. After 39?months of operation, about 53,000 tonnes of CO2 have been stored in 630?C650?m deep sandstone units of the Upper Triassic Stuttgart Formation. An extensive monitoring program integrates geological, geophysical and geochemical investigations at Ketzin for a comprehensive characterization of the reservoir and the CO2 migration at various scales. Integrating a unique field and laboratory data set, both static geological modeling and dynamic simulations are regularly updated. The Ketzin project successfully demonstrates CO2 storage in a saline aquifer on a research scale. The results of monitoring and modeling can be summarized as follows: (1) Since the start of the CO2 injection in June 2008, the operation has been running reliably and safely. (2) Downhole pressure data prove correlation between the injection rate and the reservoir pressure and indicates the presence of an overall dynamic equilibrium within the reservoir. (3) The extensive geochemical and geophysical monitoring program is capable of detecting CO2 on different scales and gives no indication for any leakage. (4) Numerical simulations (history matching) are in good agreement with the monitoring results.  相似文献   

10.
11.
Yadav  Purva 《GeoJournal》2021,86(4):1927-1941
GeoJournal - This paper attempts to capture the missing ‘distance’ puzzle in the globalization process driven by trade flows. It is widely recognized that the growing global economic...  相似文献   

12.
In Hanoi people access, expand and create water and sanitation infrastructures in multiple ways that include, but are not restricted to, external provision of networked services. Urban master planning and the construction of large technological networks aim at integrating the urban region based on circulating ‘modern ideals’ of ubiquity and standardization of infrastructures. However, centralized infrastructure provision has remained unstable and spatially uneven. We examine differently networked spaces that have emerged at the edge of Hanoi along with rapid urban change and new financing mechanisms in the past thirty years, and the ways in which urban residents engage with the various water and sanitation systems. This engagement is shaped by circulating ideals, place-specific processes of urban re-production, sector-specific dynamics, and individuals. Not only in periurban villages, but also in modern housing estates, people rebut a role as passive receptors of external services. In some instances, they create relatively stable collectives through which they provide, negotiate and complement networked infrastructure connection. Thus, people living at Hanoi’s urban edge actively re-produce water and sanitation systems beyond passive consumption of externally provided services.  相似文献   

13.
This article examines how law is implicated in the formation of place, and how place in turn can shape law. It is an empirical explication of Latour’s call for researchers to study the global through its local instantiations. Drawing upon recent theoretical work in both material culture studies and legal geography the article examines the interplay of law and material formations at one originating site, Sir Richard Arkwright’s Cromford Mills in Derbyshire in order to examine the creation and circulation of a new form of place in the late eighteenth century: the industrial scale cotton mill. It shows how a diverse range of legal elements ranging across patent law, the Calico Acts and ancient local Derbyshire lead mining laws all helped to shape that place-form, its proliferation across the United Kingdom, and ultimately further afield. In doing so the article conceptualises processes of localisation, translocalisation and thing-law by which the abstractions of both place-forms and law elements become activated through their pragmatic local emplacement. Whilst the case study concerns 200 year old place-making machinations, many of the spatio-legal articulations of Arkwright and his opponents have a surprisingly modern feel about them. The paper therefore advocates the benefits of a longitudinal, historical approach to the study of place-making, and in particular, calls for a greater attentiveness in legal geography to law’s role in the intentional formation of (work)places by their owners.  相似文献   

14.
15.
Among many of the differential interferometric synthetic-aperture radar technologies, artificial corner reflectors (ACR) are widely used in monitoring earthquake deformation and urban subsidence due to their relative stability on synthetic-aperture radar (SAR) acquisition. Apparently, the detection and extraction of ACRs on remotely sensed images would be of utmost importance. Many different geometric types of ACRs are designed to achieve maximum detection. Among them, dihedral, rectangle trihedral, and pyramidal ACRs are the most commonly employed. The cost and difficulty of deploying ACRs in the field, however, render comparison among the three types rather impractical, if not impossible. The current study attempts to tackle the issue from a physical optics perspective. Adopting radar cross section (RCS) as the measure of ACRs’ detectability, we examined the relationships between the ACRs’ RCS under vertical polarity with various parameters including the radar incident angles, width and heights of the ACRs and the azimuthal angles. The analyses indicate that under vertical polarity, among the three types of ACRs, the rectangle trihedral ACR is the most tolerant to its deploying surroundings. To verify the physical optics analysis results, we collected ENVISAT data from a variety of deployed ACRs in the Yan-Huai Basin, China, and derived their reflectance characteristics. The field data agree with the theoretical analyses. From this practice, it seems that the physical optics method might prove to be a rather economical and effective approach to design and select appropriate ACRs in field deployment.  相似文献   

16.
Hausmann  Peter 《Natural Hazards》2016,86(1):197-198

As a leading global reinsurer, Swiss Re deals with many hazards and risks for which geospatial data are crucial in order to obtain reliable assessments of expected insured losses or large losses from catastrophes. Typically, such data are used in combination with insurance data either in pricing tools to calculate premiums, tail risks and more, or in mapping tools. In natural perils pricing applications—the most important group of tools—geospatial data are usually “not visible” but are instead used to create probabilistic event sets. For example, a flood event set may define spatially if and how frequently a given location is flooded. Mapping tools, such as Swiss Re’s CatNet® (www.swissre.com/catnet), visualize the data in the form of maps which include many useful attributes per geographic location.

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17.
18.
On April 1, 2017, China announced to initiate the Xiong’an New Area (XNA) plan, which is a national-level strategy aimed at alleviating the pressures felt by Beijing and promoting the integration of the Beijing-Tianjin-Hebei (BTH) city-region. In China, a city-region can be viewed as an outcome of state spatial selectivity that aims to manage crises and maintain governance through strong state involvement. This paper attempts to provide a broad view of the XNA plan by examining it in the context of China’s long-term efforts to coordinate the BTH region, explaining the incentives associated with choosing Xiong’an, and analyzing the challenges the plan has faced. Considering that theoretical insights based on Western experience may not be applicable to China, this paper can contribute to the debate revealing the logics of city-region building in different contexts.  相似文献   

19.
Chung  Him 《GeoJournal》2021,86(3):1375-1388
GeoJournal - This paper addresses the relationship between spatial change and social process in China. Studies in Anglo-American and European cities usually suggest middle classes move into a...  相似文献   

20.
This paper draws upon Michael Watts’s work on governable spaces and “economies of violence” in the Niger Delta (2004a,b,c) and Colin Filer’s concept of the “ideology of landownership” in Papua New Guinea (1997) to explore how resource capitalism has been at the heart of violent conflict in post-colonial Melanesia. This schema of the political ecology of violence is elucidated with reference to three governable spaces – landownership, indigeneity, and nationalism; four different resource–industrial complexes – mining, oil and gas, logging, and oil palm; and the region’s three most serious conflicts to date – the Bougainville conflict, the Solomon Islands ‘ethnic tension’, and on-going violence in the Highlands of Papua New Guinea, particularly in Enga and Southern Highlands provinces. It is argued that in each of these places the story of violent conflict is ineluctably one of resource capitalism and its engagement with local socio-political contexts. In sharp contrast to the resource determinism, state-centrism and ahistoricism of much of the ‘resource conflict’ literature, attention to governmentality and scale highlights the highly contextual and contingent nature of resource-related violence in Melanesia. The diverse experiences of different regulatory approaches to the encounters between resource complexes and governable spaces across time and space are also examined, giving rise to policy implications for governing resource conflict in Melanesia.  相似文献   

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