5 resultados para Dry period

em RUN (Repositório da Universidade Nova de Lisboa) - FCT (Faculdade de Cienecias e Technologia), Universidade Nova de Lisboa (UNL), Portugal


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper describes the palaeoweathering, cementation, clay minerals association and other closely related characteristics of central Portugal allostratigraphic Tertiary units (SLD's), that can be used for palaeoclimatic interpretation and palaeoenvironmental reconstruction. Lateral and vertical changes in palaeosols are of value for improving our understanding of the autocyclic and allocyclic controls on sediment acumulation in an alluvial basin, but they can also have stratigraphic importance. In some cases it is concluded that the geomorphological setting may have been more decisive than climatic conditions to the production of the palaeoweathering. During late Palaeogene (SLD7-8), surface and near-surface silicification were developed on tectonically stable land surfaces of minimal local relief under a semi-arid climate; groundwater flow was responsible for some eodiagenesis calcareous accumulations, with the neoformation of palygorskite. Conditions during the Miocene (SLD9-11) were favourable for the smectization of the metamorphic basement and arenization of granites. Intense rubefaction associated with basement conversion into clay (illite and kaolinite), is ascribed to internal drainage during late Messinian-Zanclean (SLD12). During Piacenzian (SLD13) intense kaolinization and hydromorphism are typical, reflecting a more humid and hot temperate climate and important Atlantic fluvial drainage. Later on (Gelasian-early Pleistocene ?; SLD14). more cold and dry conditicns are interpreted, at the beginning of the fluvial incision sage. Silica cementation is identified in the upper Eocence-Oligocene ? (SLD18; the major period of silicification), middle to upper Miocene (SLD10)and upper Tortonian-Messinian (SLD11); these occurrences are compatible with either arid or semi-arid conditions and the establishment of a flat landscape upon which a silcrete was developed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Restoration of Buildings and Monuments, vol. 13, nº 6 (2007), p.389-400

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Strong consolidation is one of the most evident developments of banking markets around the world in recent decades. This change is raising questions on how and to what an extent competition is affected by the expansion of the largest banks. The aim of the present study is to measure the degree of competition in the Portuguese commercial banking market in the long-run, during the period ranging from1960 to 2013, by using the non-structural model developed by Panzar and Rosse. The main findings are that the Portuguese banking system, despite the legal restrictions in place, operated mostly in a market with some degree of competition and, at some points in time, presented some interesting competitive features. More recently, it has evolved into functioning as a cartel.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The 2001-2012 period has been one of very low growth for Portugal. This work project tries to find reasons for this slowdown. Growth in real GDP will be explained by several variables ranging from education, capital, government and world markets. Compensation of employees, capital per worker and the exports of competitors seem to explain a significant part of the slowdown. The ratio of non-tradables to tradables is also included but not significant, maybe due to a poor sample size. Stagnation then seems to be caused both by low growth in input accumulation and productivity as predicted by Amador and Coimbra in 2007.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper analyses the Portuguese stock market since it reopened in 1977, with a special focus on the evolution of the statistic and stochastic characteristics of the market return throughout this 36 year period. The market return for the period of time between 1977 and 2012 (September 28th) is estimated and then compared with the return that would have been achieved with Government bonds and treasury bills, which allows us to confirm that the hierarchy of return / risk across the different financial instruments is verified. The market risk premium for this 36 year period is also estimated and a comparison with other markets is performed, suggesting that the Portuguese market’s risk has not been compensated by an adequate return. The study also examines the evolution of the Portuguese market’s volatility in the 1977-2012 period and compares it with other markets, showing the existence of extremely high peaks during the first 11 years, but indicating a downwards trend throughout the whole period under analysis. Finally, the correlation between market returns for Portugal and for other countries and the degree of integration are estimated and their evolution throughout time is assessed, leading to the conclusion that the performance of the Portuguese stock market has become increasingly correlated with major European markets – correlation with some markets close to 0.70 from 2000 onwards-, but that country-specific risk factors are still relevant.