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1.
The 1988 Tennant Creek,northern territory,earthquakes: A synthesis   总被引:2,自引:0,他引:2  

Three large earthquakes with surface‐wave magnitudes 6.3–6.7 on 22 January 1988 were associated with 32 km of surface faulting on two main scarps 30 km southwest of Tennant Creek in the Northern Territory. These events provide an excellent opportunity to study the mechanics of midplate earthquakes because of the abundance of geological and geophysical data in the area, the proximity of the Warramunga seismic array and the ease of access to the fault zone. The 1988 earthquakes were located in the North Australian Craton in an area that had no history of moderate or large earthquakes before 1986. Additionally, no smaller earthquakes from the fault zone were identified at the Warramunga array, which is situated only 30 km from the nearest scarp, between the 1965 installation of the array and 1986. The main shocks were preceded by a swarm of moderatesized (magnitude 4–5) earthquakes in January 1987 and many smaller aftershocks throughout 1987. Careful relocation of all teleseismically recorded earthquakes from the fault zone shows that the 1987 activity was concentrated in an area only 6 km across in the gap between the two main fault scarps. The main shocks also nucleated in the centre of the fault zone near the 1987 activity. Field observations of scarp morphology indicate that the scarp is divided into three segments, each showing primarily reverse faulting. However, whereas the western and eastern segments show movement of the southern block over the northern, the central scarp segment shows the opposite, with the northern block thrust over the southern block.

Analysis of the first arrival times at Warramunga suggests that the three main shocks were associated with the western, central and eastern scarp segments, respectively. The locations of aftershocks determined using data from temporary seismograph arrays in the epicentral area define three inclined zones of activity that are interpreted as fault planes. In the western and eastern portions of the aftershock zone, these concentrations of activity dip to the south at 45° and 35°, respectively, but in the central section the aftershock zone dips to the north at 55°. Focal mechanisms derived from modelling broadband teleseismic data show thrust and oblique thrust faulting for the three main shocks. The first event ruptured unilaterally up and to the northwest on the westernmost fault segment, while the third main shock ruptured horizontally to the southeast. Modelling of repeat levelling data from the epicentral area requires at least three distinct fault planes, with the eastern and western planes dipping to the south and the central plane dipping to the north. The combination of scarp morphology, aftershock distribution and elevation data makes a strong case for rupture of fault planes in conjugate orientation during the 22 January 1988 Tennant Creek earthquakes. More than 20000 aftershocks have been recorded at Warramunga and activity continues to the present‐day with occasional shocks felt in the town of Tennant Creek and some recent off‐fault aftershocks located directly under the Warramunga seismic array. Stratigraphic relationships exposed in trenches excavated across the scarps suggest that during the Quaternary, a large earthquake ruptured the surface along one segment of the 1988 scarps.  相似文献   

2.
The impact of desertification on society is analyzed through the territorial structures by which society itself is implementing its own reproduction. Three stages of impact are pointed out, marked by elementary, functional and structural stability/vulnerability thresholds. These thresholds are not consonant, and different strategies can simultaneously raise one of them and lower another one. In this frame, three stability/vulnerability profiles are depicted: the rootedness profile (traditional small sized and low technologized society); the strengthening profile (under the effects of the engineered reinforcement); the integration profile (when traditional society is integrated in a wider and more diversified one).  相似文献   

3.
G. H. Pirie 《GeoJournal》1990,22(3):231-240
The geography of air transport to and from South Africa has been shaped powerfully by the world map of anti-apartheid, sanctions-keeping nations which close their airspace to the Republic's state-owned airline. Re-routering, involving notably the offshore west-African link to Europe, revocation of foreign landing rights and a shrinking airline network have resulted. The economic dependence of the Republic's southern African neighbours on their political adversary has dissuaded them from joining an anti-apartheid air blockade. Likewise, the penalties to black African states of denying overfying, landing and traffic rights to west-European airlines plying the South Africa route have diminished the force of the air embargo.  相似文献   

4.
This article offers an analysis of the emerging scalar configuration of the governance of the European Union. It discusses how European integration stands for a move from a collection of territorially homogenous systems of rule towards a new assemblage of territories, authorities and rights. The paper first questions the stretchy territoriality of the seemingly obvious European level. Second it analyses the sectoral differences in the evolution of the width and the depth of integration, measured as the transfer of competencies to the EU level between the Rome Treaty (1958) and the Lisbon Treaty (200y). Third it turns to the day-to-day decision-making to assess the relations between players in EU governance and finally it looks more closely at the administrative wheels of the EU machinery.  相似文献   

5.
Gaza Strip is a highly populated, small area in which the groundwater is the main water source. During the last few decades, groundwater quality has deteriorated to a limit that the municipal tap water became brackish and unsuitable for human consumption in most parts of the strip. To overcome this serious situation, several attempts were made to replace the tap water or to improve its quality by water desalination applying the reverse osmosis (RO) technology, bottled water, importing water, and storm water harvesting. Water desalination, which is widely applied in the strip, has environmental and health risks. Brine water resulting from the RO systems has adverse environmental effects, whereas the produced fresh water with very low chemical concentrations may have harmful effects on human health. Therefore, introducing international water quality standards to delineate the harmless minimum limits is necessary. Storm water harvesting can provide a partial solution for the water problems in the strip.  相似文献   

6.
Jonathan D. Mayer   《Geoforum》1980,11(4):399-407
Woods left on good farmland in Ohio and neighboring states are likely to be beech-maple woods. There may well be a dozen or more tree species present, but the most obvious, because the most common, will be beeches and sugar maples … these trees exhibit the phenomenon of ecological dominance. There can be little doubt that the other plants of the wood are adapted to the presence of the abundant beeches and maples so that to describe them as dominants in this way is good use of language. The beeches and maples determine the micro climate, and even the soil, to which all the other living things must adapt - PAUL COLINVAUX.In the social reality, despite all change, the domination of man by man is still the historical continuum that links pre-technological and technological reason. However, the society which projects and undertakes the technological transformation of nature alters the base of domination by gradually replacing personal dependence … with dependence on the “objective order of things” (on economic laws, the market, etc…) … domination now generates a higher rationality — that of a society which sustains its hierarchic structure while exploiting ever more efficiently the natural and mental resources… - HERBERT MARCUSE  相似文献   

7.
Conflicts over territory have resulted in innumerable wars and other violent incidents, but the reasons that some territory is more highly valued or volatile than other areas may not be obvious. This paper demonstrates a taxonomy for analyzing international territorial disputes that seeks to capture their tangible and symbolic dimensions and to weigh them as the international community might. Twenty-six territorial disputes, including offshore areas and separatist issues, were examined and scored according to 15 criteria for objective prominence and 7 criteria related to how a country might view the dispute in terms of its national interest. The taxonomy used Saaty’s Analytic Hierarchy Process to identify tangible and intangible properties, measure their interrelations, and produce intermediate and overall ranks. Each dispute was evaluated for prominence by examining intensifying (symbolic) factors, measures of magnitude, and characteristics that retard resolution. The magnitude of a dispute was judged to contribute the most to overall prominence, having twice the weight of the other two factors. The top five disputes in terms of prominence were the Kurdish issue, Kashmir, Tibet, Nagorno-Karabakh, and Xinjiang. The second hierarchy evaluated the disputes from the perspective of an international actor, in this case the United States. When judged by U.S. national interest, the most important factors were the deployment of U.S. forces in the claimant countries and if one of the claimants were a U.S. ally. Finally, the results from the two hierarchies were compared.  相似文献   

8.
Increasing pressure on water resources worldwide has resulted in groundwater contamination, and thus the deterioration of the groundwater resources and a threat to the public health. Risk mapping of groundwater contamination is an important tool for groundwater protection, land use management, and public health. This study presents a new approach for groundwater contamination risk mapping, based on hydrogeological setting, land use, contamination load, and groundwater modelling. The risk map is a product of probability of contamination and impact. This approach was applied on the Gaza Strip area in Palestine as a case study. A spatial analyst tool within Geographical Information System (GIS) was used to interpolate and manipulate data to develop GIS maps of vulnerability, land use, and contamination impact. A groundwater flow model for the area of study was also used to track the flow and to delineate the capture zones of public wells. The results show that areas of highest contamination risk occur in the southern cities of Khan Yunis and Rafah. The majority of public wells are located in an intermediate risk zone and four wells are in a high risk zone.  相似文献   

9.
Using entropy theory, a methodology was developed for the evaluation and redesign of groundwater quality monitoring wells in the Gaza Strip in Palestine. Essential to the methodology is the development of a Transinformation Model (TM) which yields the amount of information transfer and the dependency between the wells as a function of distance. The TM parameters, such as the minimum transinformation and the range, were employed for evaluating the network which revealed that most of the distances between wells were less than the range. It also indicated that a high percentage of redundant information existed in the network. Therefore, the network was reduced by superimposing a square pattern over the monitored area and selecting one well per square block in a stratified pattern. The methodology was tested using the chloride data collected from 1972–2000 from 417 groundwater quality monitoring wells in the Gaza Strip. The number of the groundwater quality monitoring wells in the Gaza Strip was reduced by 53%, while there was 26% redundant information based on the minimum existing distance between wells. This methodology is meant to help monitor the groundwater quality (salinity) in the Gaza Strip.  相似文献   

10.
The Northern Ireland Good Friday Agreement (GFA) signed in 1998 has been presented by many, including those in Irish nationalist circles, as a sign of a post-national de-territorialisation of Irish national identity, made possible or even necessary by globalisation. Studying the discourses of the main Irish constitutional nationalist parties in both Northern Ireland and the Irish Republic, prior to and after the GFA, this article argues that this process is best understood instead as a dialectical unfolding of deterritorialising and reterritorialising trends. The first section analyses the concepts and theories of the de/reterritorialisation debate and proposes a theoretical framework through which the de/reterritorialisation of national identities might be understood. The second section sets the groundwork for the terms in which such a framework might be applied to the territorial claims advanced by the main Irish nationalist constitutional parties. Finally, the third section examines the complex history of competing claims over the importance of territory in both cultural and political Irish nationalist movements, Specific attention is given to debates over the GFA. It is concluded that Irish nationalism has long been divided on the status of its territorial ambitions. As such recent literature on de/reterritorialism can both inform and be informed by work on Irish nation and state building.  相似文献   

11.
Arabian Journal of Geosciences - This paper presents the results of a groundwater hydrochemical assessment in the urban area of Khan Younis City in the southern Gaza Strip by measuring its...  相似文献   

12.
13.
State formation is a complex process. Using the notion of the ghetto state, the case of the West Bank and Gaza Strip are analyzed. State formation processes among the Palestinians are shown to be a direct reaction to the processes of political and military control put into operation by Israel since 1967. The continued administrative and political separation of the West Bank and Gaza from the dominant Israeli territory enable the Palestinians to formulate their own independent national identity. This includes the establishment of economic, cultural and local political organizations, providing the foundations for future statehood. Such organizational capability is indicative of the wide range of non-violent forms of power which, in many cases, are more effective than direct acts of violence against Israel. The Intifada — or popular uprising — which has been in operation since 1987 has enforced these processes of statehood formation, through its combination of both violent and non-violent forms of power.  相似文献   

14.
The present study research investigation is aimed to assess the groundwater quality for the urban area in Khan Younis City, southern Gaza Strip, for multi-domestic purposes. The physicochemical analysis of the groundwater wells shows the major ions in the order of Na+ > Mg2+ > Ca2+ > B3+ > K+ and Cl? > HCO3 ? > SO4 2? > NO3 2? > F? > PO4 3?. Groundwater quality is classified as very hard-brackish water type. Ninety-five percent of the wells are classified as saline water type with high NO3 2? concentrations. Based on water quality index (WQI), the groundwater falls into one of three categories: fair water (10%), poor water (15%), very poor (45%), and worst (30%). The high WQI values are because of high Na+, Cl?, SO4 2?, and NO3 2? concentrations, while synthetic pollution index (SPI) values indicate that most about 80% of the wells are seriously polluted. Langelier Saturation Index (LSI) indicates that most of data are either slightly scale forming or corrosive water or slightly corrosive but non-scale forming, and 75% of the wells are suitable for construction purposes (have SO4 2? concentrations <300 mg/L). The groundwater reaches alarming situation, where almost chemically unsuitable for drinking purposes and the water to be used after proper treatment such as desalination.  相似文献   

15.
《Quaternary Science Reviews》1999,18(4-5):697-709
Since 1990 archaeological research by the Catholic University of Leuven (Belgium) has been carried out at the ancient site of Sagalassos (Aǧlasun, Burdur province, Southwestern Turkey). At first, research focused on the excavation of the city and the study of the immediate vicinity which provided it with raw materials. The main objective was to obtain a clear picture of the history and development of the city. Since 1993 research has also incorporated a study of the territory of the Roman city, from prehistoric to modern times, in order to understand why the site was selected for settlement, why it developed into a middle-sized town, its economy and subsistence, how it affected and exploited the environment, its decline, and what changes have taken place in the district subsequently. The focus has now shifted towards obtaining a better understanding of the linkages between human and environment systems so that inter-relations between the two can be more readily understood. As a result, a number of environmental topics concerning the territory of the Roman city are presently being studied. This territory extended from Lake Burdur in the West to the Aksu canyon in the East, from the Aǧlasun Daǧlari in the North to Mt. Kestel in the South. Interdisciplinary research revealed that for the early Neolithic and the Roman period there was a slightly warmer climate, a richer vegetation and more fertile soils for agricultural practice.  相似文献   

16.
Organic carbon and inorganic carbonate contents previously reported for ore and pyritic shale country rocks from the McArthur area have been found to be in error because of saturation of the sulphur oxides trap during combustion of the samples. Corrected organic carbon values do not show good correlations with iron, zinc, lead, or sulphur contents.  相似文献   

17.
Jitt-Aer  Kiatkulchai  Wall  Graham  Jones  Dylan  Teeuw  Richard 《Natural Hazards》2022,113(1):185-211
Natural Hazards - The 2004 Indian Ocean tsunami led to improvements in Thailand’s early warning systems and evacuation procedures. However, there was no consideration of better aid delivery,...  相似文献   

18.
Salite  Daniela 《Natural Hazards》2019,96(3):1289-1309

This paper explores the traditional indicators that small-scale farmers in Gaza province in southern Mozambique use to predict drought events on their rain-fed farms. It analyzes the contextual situation regarding the accuracy and reliability of the traditional prediction methods under the current weather and conditions of climate uncertainty and variability, and the opportunities that their prediction methods can bring to reduce their current and future exposure and vulnerabilities to drought. Farmers use a total of 11 traditional environmental indicators to predict drought, either individually or combined, as required to increase their prediction certainty. However, the farmers perceive that current unpredictability, variability, and changes in weather and climate have negatively affected the interpretation, accuracy, and reliability of most of their prediction indicators, and thus their farming activities and their ability to predict and respond to drought. This, associated with the reduced number of elders in the community, is causing a decline in the diversity, and complexity of interpretation of indicators. Nonetheless, these difficulties have not impeded farmers from continuing to use their preferred prediction methods, as on some occasions they continue to be useful for their farming-related decisions and are also the main, or sometimes only, source of forecast. Considering the role these methods play in farmers’ activities, and the limited access to meteorological forecasts in most rural areas of Mozambique, and the fact that the weather and climate is expected to continually change, this paper concludes that it is important to enhance the use of traditional prediction methods. However, the increase of the accuracy and reliability, and continued existence of the methods depends on the farmers’ own abilities to enhance, preserve, and validate them by tailoring the traditional methods used to work with the new environmental, weather, and climatic conditions, or through the development of new methods.

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19.
Angelo Turco 《GeoJournal》2004,60(4):329-337
Territorial symbolism in sub-Saharan Africa calls to mind multiple forms of knowledge. More particularly, territorial significance is fed both by magical and sacred beliefs and by knowledge based on empirical observation and concrete practices. These two types of knowledge differ widely as to their nature, the procedures by which they are formed, and the cultural values they embody. Nevertheless, semantic interaction between mythical knowledge and technical knowledge is remarkably rich. By blurring the distinction between mythos and techne, this semantic interaction seems to constitute an important cultural tool for building feelings of social security in that it reinforces and stabilizes socio-geographic patterns, and more especially those which regulate access to space and natural resources. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

20.
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