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1.
Relations between the United States and Europe have been quite volatile over the past five years. This volatility is not just a product of disagreements over the American invasion of Iraq. It is tied to a set of fundamental challenges to the geopolitical arrangements and understandings that emerged in the wake of World War II. Three challenges were of particular importance: the fall of the Iron Curtain, the Balkan crisis of the 1990s, and the election of a presidential administration in Washington, DC, which adopted a neoconservative geopolitical agenda. The global impacts of this agenda were heightened by the September 11, 2001, attacks on the United States of America. The U.S. response exposed fundamental differences between the U.S. and Europe on the use of international military forces in the “war on terrorism,” the role of NATO, and the U.S. government’s effort to force “regime change” in Iraq. Europe’s reaction to U.S. policy has not been uniform, however. At the governmental level, fundamental differences have emerged among European countries. The United States has sought to highlight those differences, suggesting that the U.S. favors “disaggregation” in Europe, even as it trumpets the virtues of a uniform response to the threat of terrorism. The future trajectory of U.S.-European relations is likely to be shaped by intersections between Europe’s struggles with integration and the U.S.’s evolving global geopolitical posture, which could move in either a hegemonic or a globalist direction.  相似文献   

2.
The sediment-hosted disseminated gold deposits in the Oinling region are of sedimentation-slight-metamorphic origin superimposed by hydrothermal reworking at moderate-low temperatures and are well comparable with the typical Carlin gold deposits in the United States.In view of the confusing concept concerning the “sediment-hosted”and “Carlin-type” gold deposits,the authors propose that the term“sediment-hosted gold deposit”should be used in a broad sense which encompasses at least the four subtypes,i.e.,the Carlin type,the metamorphic fine clastic type,the hydrothermal sedimentary type and the vein type.In oter words,the “Carlin-type”should not be used as a synonym for “sediment-hosted”but is recommended as a subtype under the general category of “sediment-hosted gold deposits”  相似文献   

3.
Eugene J. Palka 《GeoJournal》1995,37(2):201-208
This paper revisits and interrelates the scope of military geography and the changing role of the military, two themes previously addressed in the 1993 and 1994 special editions ofGeoJournal. I begin by tracing the evolution of military geography in the US from World War I through the end of the Gulf War to reveal the demise of the subfield within American academic geography. Within the context of the post-Cold War era, I describe the military's reorientation and emphasize the need and opportunity to broaden the scope of military geography accordingly. The military's current operating environment is best characterized by operations other than war, undertaken on an unprecedented scale. Military geographers and regional, systematic, and technical experts throughout the discipline now have an unparalleled opportunity to contribute to the success of peacekeeping, humanitarian, and disaster assistance missions with which the military is currently preoccupied. Initiatives by academic geographers would not only enhance mission accomplishment from the military and federal government's perspective, but might also help to revive military geography as a legitimate subfield by demonstrating that military geographic endeavors can be both socially responsible and politically correct, particularly within operations other than war.  相似文献   

4.
This paper explores the recent industrial relocation of Hong Kong manufacturing firms in the Pearl River Delta. Based on a combination of recent surveys, four in-depth case studies and nearly 20 firm interviews through the end of 2008, the paper argues that in response to a dynamic business environment in the region, some Hong Kong manufacturing firms in the PRD are forced to design new spatial strategies. The paper also identifies the different relocation strategies adopted by Hong Kong manufacturing firms, namely, total relocation, stratified relocation and “pseudo relocation”. The industrial space of Hong Kong manufacturing firms will be expanded beyond the PRD. In addition, the new round of relocation of Hong Kong manufacturers is a response to the initiative ushered in by the provincial and local governments in order to achieve the objectives of industrial upgrading, sustainable environment and regional balanced development.  相似文献   

5.
Joseph Palis 《GeoJournal》2009,74(3):227-234
My paper aims to ask what space characterizes the various constructs of orientalism and othering in the early short films of Thomas Edison. Using Lefebvre’s concept that social space “subsumes things produced, and encompasses their interrelationships in their coexistence and simultaneity” in these early shorts, I will look at three Biograph actualities found at the Library of Congress-American Memory page to show how space is manifested and negotiated onscreen. I will examine Edison’s “Filipinos Retreat From Trenches”, “Capture of Trenches at Candaba” and “U.S. Troops and Red Cross in the Trenches Before Caloocan” which were all released in 1899. These reenacted short films were shot during the tumultuous years of the Spanish-American War. In the Biograph shorts, the privileged positions of both Spanish and American forces in relation to the annexation of a foreign land in world history books is indicative of the tendency to de-emphasize the contribution of the native population in the war. Manthia Diawara has said that “space is related to power and powerlessness, insofar as those who occupy the center of the screen are usually more powerful than those in the background or completely absent from the screen.” The spatial hierarchies and spatially situated images in Edison’s short films show how historically configured power relations encrypted oppression to its external “others” through the cinematic apparatus.
Joseph PalisEmail:
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6.
For many migrants from Latin America, “Hispanic/Latino(a)” is an identity that they encounter in the United States with which they were unfamiliar in their home countries and must negotiate in their everyday lives in a new context. Specifically, immigrants from Central America are unlikely to see themselves as “Hispanic” or “Latino(a)” prior to living in the United States, more often identifying with their home country, city, town, village, or neighborhood. This paper draws on racialization theory and twenty-seven in-depth interviews with Central American immigrants in Atlanta, GA to examine this process of identity negotiation across the traditionally black/white racialized landscapes of a “New South” city. Interview participants adopt a racialized Hispanic identity through a complex process involving the interplay between how they think of themselves and their perceptions of how native-born Atlantans view them. The interview analysis presented herein demonstrates that although Central American immigrants actively negotiate a Hispanic racialized moniker, they do so within an urban context dominated by native-born residents whose racialized assumptions lump Spanish-speaking, brown skinned individuals into a monolithic “Mexican” category. Thus the ways in which racialized difference is constructed in contemporary Atlanta for recent Central American immigrants is very much bound up in such false presumptions of national identity and cultural group belonging.  相似文献   

7.
The Niger Delta question represents one of the most intractable sources of political destabilization, constitutes a profound threat to national security, and economic development of the Nigerian state. Therefore, the study of the intricate dynamics among multinational oil corporations, the Nigerian State, and insurgent militias illuminates the root causes, societal schisms and the political economy of resource induced conflicts in Africa’s major oil producing nation state. This case study illustrates and explicates the “paradox of plenty”, the “resource curse”, the “shadow state syndrome”, and the debilitating effects of petroleum politics in Nigeria. Economic exploitation of the region’s vast crude oil reserves by multinationals and government authorities is juxtaposed with the specter of environmental devastation, excruciating poverty, and recurrent rule of impunity. National elite contestations concerning the legalities of resource control, internecine squabbles over revenue allocation formulas and derivation principles have been compounded by incessant disruptions of crude oil pipelines, necessitating drastic reduction in the country’s petroleum output and revenues derived from the global economy. Due to the multi-layered dimensions of the effects of crude oil, guns, profits, and geo-territorial instability, the protracted problems of the Niger Delta thus, provides us with pertinent analytical and contextual frameworks for the study of the dynamics, volatility and transparency issues in global extractive industries. In the muddled rivers and creeks of the Niger Delta, characterized by regional destabilization, there has emerged a clandestine economy of protection syndicates, marked exponential increase in kidnappings and targeting of expatriate workers, as well as state sponsored military reprisals against self-styled insurgents, warlords, and militia movements.  相似文献   

8.
The area lies between Hugli river in the northwest and Bidyadhari river in the east and includes the East Kolkata Wetlands. The East Kolkata Wetlands is included in the List of Wetlands of International Importance (“Ramsar List”), as per the Convention on Wetlands signed in Ramsar, Iran, in 1971. This wetland has been declared as a Ramsar site on the 19th August 2002 (Ramsar site no. 1208) and therefore has acquired an international status. The area is a part of the lower deltaic plain of the Bhagirathi–Ganga river system and is generally flat in nature. The sub-surface geology of the area is completely blanketed by the Quaternary fluviatile sediments comprising a succession of clay, silty clay, sand and sand mixed with occasional gravel. The Quaternary aquifer is sandwiched between two clay sequences. The confined aquifer is made up of moderately well sorted sand and reflects fluviatile environment of deposition. The regional groundwater flow direction is from east to west. Detailed geochemical investigations of 40 groundwater samples along with statistical analysis (for example, correlation and principal component analysis) on these chemical data reveal: (i) four types of groundwater quality, for example, good, poor, very poor and water unsuitable for drinking purpose, (ii) four hydrochemical facies which may be assigned to three broad types such as “fresh”, “blended”, and “brackish” waters, (iii) the evolution of the “blended” water is possibly due to hydraulic mixing of “fresh” and “brackish” waters within the aquifer matrix and/or in well mixing, and (iv) absence of Na–Cl facies indicates continuous flushing of the aquifer.  相似文献   

9.
The article is about the role of civil society organizations in the governance of the Montréal metropolitan region. It identifies a high level of cooperation around metropolitan scale issues on the part of these organizations. In the Montréal region, government agencies as well as private corporations demonstrate readiness to work alongside civil society organizations on joint projects. Evidence of this type of collaboration is particularly strong in the case of economic development, neighbourhood revitalization and cultural initiatives. This form of cooperation is perceived as a manifestation of the so-called “Québec model” and is an asset for the Montréal metropolitan region. The article demonstrates that interventions that involve social organizations are more likely to be successful than those that turn their back on these organizations.  相似文献   

10.
Elizabeth Chacko 《GeoJournal》2007,68(2-3):131-140
This paper assesses the mutual impact of returning Indian-origin skilled workers on the cities of Bangalore (Bengaluru) and Hyderabad, which have emerged as India’s leading “tech cities”. During the 1970s and 1980s, there was concern that India was losing its educated workforce to the West, particularly to the United States through a phenomenon known as “brain drain”. More recently, there is evidence that reverse brain drain is occurring, as U.S.-trained Indian professionals are returning to their home country in increasing numbers to take advantage of new growth and employment opportunities. The effects of this skilled, transnationally active labor force on various sectors of the economy, on the social and physical infrastructure of Bangalore and Hyderabad and in forging and solidifying transnational linkages between India and the United States are explored in this paper. This study also investigates the reasons why successful US professionals of Asian-Indian origin are returning to their home country via a series of personal interviews. The paper offers Bangalore and Hyderabad as “worldwide leading cities” with a niche status in the global Information Technology (IT) sector.  相似文献   

11.
This study presents the results of both field and laboratory tests that have been undertaken to assess liquefaction susceptibilities of the soils in Kütahya city, located in the well-known seismically active fault zone. Liquefaction potentials of the sub-surface materials at Kütahya city were estimated by using the geological aspect and geotechnical methods such as SPT method of field testing. And, the data obtained have been mapped according to susceptibility and hazard. The susceptibility map indicated “liquefable” and “marginally liquefable” areas in alluvium, and “non-liquefable” areas in Neogene unit for the magnitude of earthquake of M=6.5; whereas, liquefaction hazard map produced by using of liquefaction potential index showed the severity categories from “very low” to “high.” However, a large area in the study area is prone to liquefy according to liquefaction susceptibility map; the large parts of the liquefable horizon are mapped as “low” class of severity by the use of the liquefaction potential index. It can be said that hazard mapping of liquefaction for a given site is crucial than producing liquefaction susceptibility map for estimating the severity. Both the susceptibility and hazard maps should be produced and correlated with each other for planning in an engineering point of view.  相似文献   

12.
The geological-geophysical, methological, and economic aspects of extraction and utilization of petrothermal resources (“hot dry rock thermal”) for thermal and electric energy production were considered. Heat collectors are hydraulic fracturing zones of natural or artificially made cracks in the crystalline rocks of the basement; these rocks have higher temperature and can be a kind of “thermal cauldron.” Detection of such “collectors” can be carried out by geophysical methods. When pumped out of wells and warmed to 100–300°C, waters function as a heat transfer for thermal energy supply and electric energy generation. If the technical problem of the rapid drilling of 6–10 km wells could be solved, then petrothermal energy will become competitive with the traditional types of energy production and supply.  相似文献   

13.
High-resolution manganese K-edge X-ray absorption near edge structure spectra were collected on a set of 40 Mn-bearing minerals. The pre-edge feature information (position, area) was investigated to extract as much as possible quantitative valence and symmetry information for manganese in various “test” and “unknown” minerals and glasses. The samples present a range of manganese symmetry environments (tetrahedral, square planar, octahedral, and cubic) and valences (II to VII). The extraction of the pre-edge information is based on a previous multiple scattering and multiplet calculations for model compounds. Using the method described in this study, a robust estimation of the manganese valence could be obtained from the pre-edge region at 5% accuracy level. This method applied to 20 “test” compounds (such as hausmannite and rancieite) and to 15 “unknown” compounds (such as axinite and birnessite) provides a quantitative estimate of the average valence of manganese in complex minerals and silicate glasses. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

14.
Both published and original data are used for the analysis of the stratigraphic position and taxonomic characteristics for acanthomorphic microfossils of the Pertatataka type in Lower Vendian sediments of the central and southeastern Siberian Platform and its surrounding structures. Four taxonomically different microbiotas are distinguished in sections of the Nepa-Botuoba, Fore-Patom; Syugdzher, Anabar, Zhuya-Lena, and Berezovo lithotectonic zones: two diverse (Nepa and Ura) and two impoverished (Otradnino and Torga) each including diagnostic Early Vendian taxa. Beyond the Siberian Platform, genera and species characterizing these microbiotas occur in single assemblages and represent diagnostic taxa of the second (Tc-Sr-Vl) and third (Ti-Cg-Mp) zones of the acritarch scale proposed by Australian geologists as a biostratigraphic basis for subdividing the Ediacarian of the Standard stratigraphic scale (SSS). In the Russian General stratigraphic scale, the distribution of Pertatataka acritarchs corresponds to the Lower Vendian. The appearance and mass development of acanthomorphic microorganisms represents a global biological event, which should be taken into consideration as a biostratigraphic criterion for defining the Vendian System. For substantiating age, the following species among diagnostic Lower Vendian forms of East Siberia should be used: Appendisphaera grandis, “Appendisphaera” tabifica, A. tenuis, Ceratosphaeridium glaberosum, Dicrospinosphaera virgata, Multifronsphaeridium pelorium, “Polygonium” cratum, Tanarium conoideum, Variomargosphaeridium litoschum, and Talakania obscura. These taxa are readily recognizable, morphologically stable, and characterized by their wide lateral distribution and relatively narrow stratigraphic range. Their occurrence in the upper part of the Dal’nyaya Taiga Group of the Baikal-Patom region indicates that host sediments should be attributed to the Lower Vendian, not the Upper Riphean as is currently accepted.  相似文献   

15.
The current theoretical development of the analysis of compositional data in the article by Aitchison and Egozcue neglects the use of Harker’s variation diagrams and other similar plots as “meaningless” or “useless” on compositional data. In this work, it is shown that variation diagrams essentially are not a correlation tool but a graphical representation of the mass actions and mass balances principles in the context of a given geological system, and, when they are used correctly, they provide vital information for the igneous petrologist. The qualitative validity of the “spurious trends” in these diagrams is also shown, when they are interpreted in their proper geological framework. The example previously used by Rollinson to test the usefulness of the log-ratio transformation in the Aitchison and Egozcue article is revisited here in order to fully illustrate the proper use of this tool.  相似文献   

16.
The Katanga province, Democratic Republic of Congo, hosts world-class cobalt deposits accounting for ~50% of the world reserves. They originated from sediment-hosted stratiform copper and cobalt sulfide deposits within Neoproterozoic metasedimentary rocks. Heterogenite, the main oxidized cobalt mineral, is concentrated as “cobalt caps” along the top of silicified dolomite inselbergs. The supergene cobalt enrichment process is part of a regional process of residual ore formation that also forms world-class “manganese cap” deposits in western Katanga, i.e., the “black earths” that are exploited by both industrial and artisanal mining. Here, we provide constraints on the genesis and the timing of these deposits. Ar–Ar analyses of oxidized Mn ore and in situ U–Pb SIMS measurements of heterogenite yield Mio–Pliocene ages. The Ar–Ar ages suggest a multi-phase process, starting in the Late Miocene (10–5 Ma), when the metal-rich substratum was exposed to the action of meteoric fluids, due to major regional uplift. Further oxidation took place in the Pliocene (3.7–2.3 Ma) and formed most of the observed deposits under humid conditions: Co- and Mn-caps on metal-rich substrata, and coeval Fe laterites on barren areas. These deposits formed prior to the regional shift toward more arid conditions in Central Africa. Arid conditions still prevailed during the Quaternary and resulted in erosion and valley incision, which dismantled the metal-bearing caps and led to ore accumulation in valleys and along foot slopes.  相似文献   

17.
Anomalous high fluoride concentration up to 7.59 mg/dm3 is found in groundwater from “La Victoria” area. This water is used to supply drinking water to Hermosillo City, Sonora. Geochemistry of groundwater, relationship between physicochemical parameters, hydrogeology and geologic setting were correlated to define the origin and the geochemical mechanisms of groundwater fluorine enrichment. High fluoride concentration is associated with high bicarbonates, pH and temperature, and it decreases toward the west and south of the area. Fluoride is in negative correlation to calcium concentration. Sodium sulphate facies of regional deep water flow are related to high fluoride concentration. High electric resistivity rocks associated with granites from the Sierra Bachoco basement might be the deep source of fluoride. Outcropping of Sierra Bachoco in the west causes upward regional flow. Groundwater of longer residence time can be pumped there. The anomalous area is restricted to “La Victoria” because calcareous paleozoic rocks outcrop to the south.  相似文献   

18.
Rural communities throughout the postindustrial world are in the midst of a significant transition, sometimes referred to as rural restructuring, as traditional land uses, economic activities, and social arrangements transition to those associated with “post-productivist” or “multifunctional” landscapes. Amenity migration, the movement of people based on the draw of natural and/or cultural amenities, can be thought of as both driver and implication of this transition, resulting in significant changes in the ownership, use, and governance of rural lands, as well as in the composition and socioeconomic dynamics of rural communities. In concert with other social, economic and political processes, amenity migration is contributing to the fundamental transformation of rural communities throughout the world. This paper presents a review of the social science literature related to the concept of amenity migration, focusing on the ways in which it has been conceptualized, theorized, and documented by different communities of scholars. We then profile and summarize diverse perspectives on drivers and socioeconomic impacts, highlighting emerging challenges and opportunities related to this type of migration occurring at multiple scales and in multiple sites. The paper also identifies and discusses particular areas where further research is needed.  相似文献   

19.
This paper demonstrates techniques for pre-eruption prediction of lahar-inundation zones in areas where a volcano has not erupted within living memory and/or where baseline geological information about past lahars could be scarce or investigations to delimit past lahars might be incomplete. A lahar source (or proximal lahar-inundation) zone is predicted based on ratio of vertical descent to horizontal run-out of eruptive deposits that spawn lahars. Immediate post-eruption distal lahar-inundation zones are predicted based on “pre-eruption” distal lahar-inundation zones and on spatial factors derived from a digital elevation model. Susceptibility to distal lahar-inundation is estimated by weights-of-evidence, by logistic regression and by evidential belief functions. Predictive techniques are applied using a geographic information system and are tested in western part of Pinatubo volcano (Philippines). Predictive maps are compared with a forecast volcanic-hazard map through validation against a field-based volcanic-hazard map. The predictive model of proximal lahar-inundation zone has “true positive” prediction accuracy, “true negative” prediction accuracy, “false positive” prediction error and “false negative” prediction error that are similar to those of the forecast volcanic-hazard map. The predictive models of distal lahar inundation zones have higher “true positive” prediction accuracy and lower “false negative” prediction error than the forecast volcanic-hazard map, although the latter has higher “true negative” prediction accuracy and lower “false positive” prediction error than the former. The results illustrate utility of proposed predictive techniques in providing geo-information could be used, howbeit with caution, for planning to mitigate potential lahar hazards well ahead of an eruption that could generate substantial source materials for lahar formation.  相似文献   

20.
We apply the logic of clinical epidemiological studies to quantify the accuracy of mapping sinkholes by ALSM in the 750 km2 Pinellas County. By such studies, a new diagnostic procedure is tested by comparing the diagnoses in a clinical trial to diagnoses on the same patients from a more reliable, but more elaborate and expensive procedure (“gold standard” in epidemiological context). A relatively undeveloped, 65 km2 focus area where we have aerial photographs that are effectively contemporaneous with the ALSM flights serves as the “clinical trial”. The xy-locations in the focus area are the “patients” in the trial. The “diagnostic test” for having “sinkhole disease” is inclusion in a database of sinkhole polygons delimited by ALSM contours (“ALSM-alone”), as detailed in Part 1. The standard of comparison (“gold standard” would be an overstatement in the absence of geophysical testing) is inclusion in a database of sinkhole outlines derived by best judgment of conjunctive interpretation of ALSM and aerial photography. GIS intersections that indicate the sensitivity and specificity of the test (ALSM-alone) are 43 and 98.3%, respectively, and, in the focus area where the prevalence of “sinkhole disease” is 4.7%, the positive and negative predictive values are 55.5 and 97.2%, respectively. Over much of the rest of the county, where only the test can be applied, the prevalence of sinkholes is sufficiently small that it cannot be determined to be any different from zero given the paucity of interpreted sinkholes (positive diagnoses) and the low specificity of the test method. The conclusion, therefore, is that contemporaneous aerial photography is essential to compile an ALSM-derived database that aims to state that the given xy-points lay inside or outside of topographic depressions in the covered karst of west-central Florida.  相似文献   

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