Emigration,return, immigration: a review and evaluation of Greece's postwar experience of international migration     

Fakiolas R  King R 《International journal of population geography : IJPG》1996,2(2):171-190

"This paper offers a review and evaluation of the Greek experience of international migration.... The analysis is based partly on available published data, and partly on qualitative appraisals. Three major international migration phases are analysed--emigration, return migration and immigration--and the main socio-economic and cultural effects of these migration trends are discussed. The paper pays particular attention to the recent mass immigration movements, noting their heterogeneity...and describing their impact on the Greek labour market. The article concludes with some comments on the difficulties of formulating a Greek migration policy in the light of the country's location, open borders and internationalized economy."  相似文献   

Computational Methods of Multivariate Analysis in Physical Geography | P.M. Mather, 1976. Wiley,Chichester, 532 pp., £13.75, U.S. $26.15     

C.A.M. King 《Earth》1977,13(2):201-202

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Tilted electromagnetic Bianchi type III cosmological solution     

D. Lorenz 《Astrophysics and Space Science》1982,85(1-2):59-61

An exact cosmological solution to the Einstein-Maxwell equations for the case of Bianchi type III symmetry with stiff matter and an electromagnetic field is constructed. The behaviour of the solution near the singularity and at late stages of the expansion is investigated.  相似文献   

Results from a Multi-disciplinary Sedimentary Pilot Study of Tectonic Lake Iznik (NW Turkey) – Geochemistry and Paleolimnology of the Recent Past     

Sven O. Franz  Lorenz Schwark  Cathrin Brüchmann  Burkhard Scharf  Ralf Klingel  Jon D. Van Alstine  Namık Çagatay  Umut B. Ülgen 《Journal of Paleolimnology》2006,35(4):715-736

A limnogeological reconnaissance study was carried out on Lake Iznik, located in the southeast of the Marmara region of Turkey, involving a seismic survey and collection of short sediment cores. This lake is located on the middle branch of the North Anatolian Fault Zone (NAFZ), a transform plate boundary between the Eurasian and Anatolian Plates. It is, therefore, tectonically active and offers an opportunity to investigate the interplay of sedimentary and seismo-tectonic processes, as well as climate change and human impact in the region. Short cores of the three sub-basins, maximum length of 35.5 cm, recovered non-laminated, blackish clays and silts with varying amounts of biogenic and minerogenic (allochthonous, autochthonous) material, which documented almost the last 80 years of deposition and environmental history. High sedimentation rates in the deeper core sections are accompanied by changes in land use (conversion of woodland to farmland) in the northern areas of Lake Iznik, which caused the deposition of more weathered material (high K/Na ratios) and higher contents of Mn in the lake. A tendency towards eutrophic conditions within the last 20 years is indicated by high nutrient content (N, TOC, P), decreasing C/N-ratios, and characteristic diatom and cladoceran associations. Also increased pollution is revealed by higher Pb, Cu, and Zn contents and increased supply of human and animal faeces (high coprostanol content) during the last two decades. But simultaneous lower sedimentation rates towards the core tops complicate the reconstruction of recent and past eutrophication and pollution states of Lake Iznik. This requires an extension of the pilot study and deeper sediment cores, to recover non-anthropogenic influenced sediment levels.  相似文献   

CO₂ solubility and speciation in intermediate (andesitic) melts: the role of H₂O and composition     

P.L. King  J.R. Holloway 《Geochimica et cosmochimica acta》2002,66(9):1627-1640

We determined total CO₂ solubilities in andesite melts with a range of compositions. Melts were equilibrated with excess C-O(-H) fluid at 1 GPa and 1300°C then quenched to glasses. Samples were analyzed using an electron microprobe for major elements, ion microprobe for C-O-H volatiles, and Fourier transform infrared spectroscopy for molecular H₂O, OH⁻, molecular CO₂, and CO₃²⁻. CO₂ solubility was determined in hydrous andesite glasses and we found that H₂O content has a strong influence on C-O speciation and total CO₂ solubility. In anhydrous andesite melts with ∼60 wt.% SiO₂, total CO₂ solubility is ∼0.3 wt.% at 1300°C and 1 GPa and total CO₂ solubility increases by about 0.06 wt.% per wt.% of total H₂O. As total H₂O increases from ∼0 to ∼3.4 wt.%, molecular CO₂ decreases (from 0.07 ± 0.01 wt.% to ∼0.01 wt.%) and CO₃²⁻ increases (from 0.24 ± 0.04 wt.% to 0.57 ± 0.09 wt.%). Molecular CO₂ increases as the calculated mole fraction of CO₂ in the fluid increases, showing Henrian behavior. In contrast, CO₃²⁻ decreases as the calculated mole fraction of CO₂ in the fluid increases, indicating that CO₃²⁻ solubility is strongly dependent on the availability of reactive oxygens in the melt. These findings have implications for CO₂ degassing. If substantial H₂O is present, total CO₂ solubility is higher and CO₂ will degas at relatively shallow levels compared to a drier melt. Total CO₂ solubility was also examined in andesitic glasses with additional Ca, K, or Mg and low H₂O contents (<1 wt.%). We found that total CO₂ solubility is negatively correlated with (Si + Al) cation mole fraction and positively correlated with cations with large Gibbs free energy of decarbonation or high charge-to-radius ratios (e.g., Ca). Combining our andesite data with data from the literature, we find that molecular CO₂ is more abundant in highly polymerized melts with high ionic porosities (>∼48.3%), and low nonbridging oxygen/tetrahedral oxygen (<∼0.3). Carbonate dominates most silicate melts and is most abundant in depolymerized melts with low ionic porosities, high nonbridging oxygen/tetrahedral oxygen (>∼0.3), and abundant cations with large Gibbs free energy of decarbonation or high charge-to-radius ratio. In natural silicate melt, the oxygens in the carbonate are likely associated with tetrahedral and network-modifying cations (including Ca, H, or H-bonds) or a combinations of those cations.  相似文献   

Turquoise   总被引：1，自引：0，他引：1  

R. J. King 《Geology Today》2002,18(3):110-114

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An artificial meteor on Titan?     

Ralph D Lorenz 《Astronomy& Geophysics》2002,43(5):5.14-5.18

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Gravity evidence for a larger Limpopo Belt in southern Africa and geodynamic implications   总被引：2，自引：0，他引：2  

R. T. Ranganai  A. B. Kampunzu  E. A. Atekwana  B. K. Paya  J. G. King  D. I. Koosimile  E. H. Stettler 《Geophysical Journal International》2002,149(3):F9-F14

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On the land use in Three Gorges Reservoir area     

HE Longhua  Lorenz King  JIANG Tong 《地理学报》2003,13(4):416-422

In this study the arable land changes in two counties (Zigui and Xingshan) in the Three Gorges Reservoir area in China are investigated. The statistical data from the officially published statistical books are used to study these changes in the two counties during the past 50 years since 1949. The changes of arable land, changes of arable land per capita, and changes of multiple crop index in Zigui and Xingshan counties are examined. Using an index method, we conclude that the two counties are critical in the sustainable utilization of arable land.  相似文献   

Recent Rapid Regional Climate Warming on the Antarctic Peninsula   总被引：15，自引：1，他引：15  

David G. Vaughan  Gareth J. Marshall  William M. Connolley  Claire Parkinson  Robert Mulvaney  Dominic A. Hodgson  John C. King  Carol J. Pudsey  John Turner 《Climatic change》2003,60(3):243-274

The Intergovernmental Panel on Climate Change (IPCC) confirmed that mean global warming was 0.6 ± 0.2 °C during the 20th century and cited anthropogenic increases in greenhouse gases as the likely cause of temperature rise in the last 50 years. But this mean value conceals the substantial complexity of observed climate change, which is seasonally- and diurnally-biased, decadally-variable and geographically patchy. In particular, over the last 50 years three high-latitude areas have undergone recent rapid regional (RRR) warming, which was substantially more rapid than the global mean. However, each RRR warming occupies a different climatic regime and may have an entirely different underlying cause. We discuss the significance of RRR warming in one area, the Antarctic Peninsula. Here warming was much more rapid than in the rest of Antarctica where it was not significantly different to the global mean. We highlight climate proxies that appear to show that RRR warming on the Antarctic Peninsula is unprecedented over the last two millennia, and so unlikely to be a natural mode of variability. So while the station records do not indicate a ubiquitous polar amplification of global warming, the RRR warming on the Antarctic Peninsula might be a regional amplification of such warming. This, however, remains unproven since we cannot yet be sure what mechanism leads to such an amplification. We discuss several possible candidate mechanisms: changing oceanographic or changing atmospheric circulation, or a regional air-sea-ice feedback amplifying greenhouse warming. We can show that atmospheric warming and reduction in sea-ice duration coincide in a small area on the west of the Antarctic Peninsula, but here we cannot yet distinguish cause and effect. Thus for the present we cannot determine which process is the probable cause of RRR warming on the Antarctic Peninsula and until the mechanism initiating and sustaining the RRR warming is understood, and is convincingly reproduced in climate models, we lack a sound basis for predicting climate change in this region over the coming century.  相似文献