927 resultados para Compensation degree


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Whole-rock basalt samples from the upper half of Deep Sea Drilling Project Hole 504B have oxygen-isotope compositions typical of mid-ocean-ridge basalts which have experienced a moderate degree of low-temperature alteration by sea water. By contrast, d18O values in the lower half of the hole correspond to basalts which have experienced almost no detectable oxygen-isotope alteration. These observations suggest that the overall water/rock ratio was lower in the lower half of the drilled crust. A correlation between d18O values and 87Sr/86Sr ratios suggests that the water/rock ratio, rather than temperature variation, was the main factor determining basalt d18O values. Hydrogen-isotope data appear to be consistent with a low water/rock ratio in the lower part of the crust.

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Boron contents and boron isotopic compositions were determined for the uppermost 1.3 km section of typical 6.2 Ma oceanic crust from DSDP/ODP Hole 504B, Costa Rica Rift, Galapagos Spreading Center. Both the boron content and the d11B value in the oceanic crust are controlled by two types of alteration: 1. (1) low-temperature alteration (0 to 60°C; Zones I and II) and 2. (2) high-temperature hydrothermal alteration (200 to 400°C; Zones III and IV). Basalts subjected to the low-temperature alteration are characterized by their relatively high boron contents (0.69 to 19.3 ppm) and high d11B values (+2.2 to +10.6?), indicating uptake of boron into secondary phases in equilibrium with seawater or evolved seawater. Hydrothermally altered basalts contain less abundant boron (0.17 to 0.52 ppm) and relatively constant d11B values (?0.1 to +1.0?). Although basalts from the upper part of these hydrothermal zones (<1300 mbsf) show equilibrated boron content and d11B value with aqueous fluid, effective leaching of boron from basalt is predominant in the lower part (>1300 mbsf). Original boron content and d11B value of the Hole 504B MORB were 0.35 ppm and +0.2?, respectively. The present data provide fundamental information in understanding of the distribution of boron and boron isotopes in the oceanic crust.

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Five sites were drilled along a transect of the Walvis Ridge. The basement rocks range in age from 69 to 71 m.y., and the deeper sites are slightly younger, in agreement with the sea-floor-spreading magnetic lineations. Geophysical and petrological evidence indicates that the Walvis Ridge was formed at a mid-ocean ridge at anomalously shallow elevations. The basement complex, associated with the relatively smooth acoustic basement in the area, consists of pillowed basalt and massive flows alternating with nannofossil chalk and limestone that contain a significant volcanogenic component. Basalts are quartz tholeiites at the ridge crest and olivine tholeiites downslope. The sediment sections are dominated by carbonate oozes and chalks with volcanogenic material common in the lower parts of the sediment columns. The volcanogenic sediments probably were derived from sources on the Walvis Ridge. Paleodepth estimates based on the benthic fauna are consistent with a normal crustal-cooling rate of subsidence of the Walvis Ridge. The shoalest site in the transect sank below sea level in the late Paleocene, and benthic fauna suggest a rapid sea-level lowering in the mid-Oligocene. Average accumulation rates during the Cenozoic indicate three peaks in the rate of supply of carbonate to the sea floor, that is, early Pliocene, late middle Miocene, and late Paleocene to early Eocene. Carbonate accumulation rates for the rest of the Cenozoic averaged 1 g/cm**2/kyr. Dissolution had a marked effect on sediment accumulation in the deeper sites, particularly during the late Miocene, Oligocene, and middle to late Eocene. Changes in the rates of accumulation as a function of depth demonstrate that the upper part of the water column had a greater degree of undersaturation with respect to carbonate during times of high productivity. Even when the calcium carbonate compensation depth (CCD) was below 4400 m, a significant amount of carbonate was dissolved at the shallower sites. The flora and fauna of the Walvis Ridge are temperate in nature. Warmer-water faunas are found in the uppermost Maastrichtian and lower Eocene sediments, with cooler-water faunas present in the lower Paleocene, Oligocene, and middle Miocene. The boreal elements of the lower Pliocene are replaced by more temperate forms in the middle Pliocene. The Cretaceous-Tertiary boundary was recovered in four sites drilled, with the sediments containing well-preserved nannofossils but poorly preserved foraminifera.

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This paper analyzes the influence of the East Asian crisis and the subsequent reforms on the oligopolistic nature of the Thai banking industry. Since the crisis, there have been substantial changes in competitive environment, including a decline in the family ownership of banks as well as the arrival of new entrants. How did these changes affect a banking industry in which the six largest local banks accounted for over 70 percent of market share? The estimated Lerner index from Bresnahan's [1989] conjectural variation model indicates the possibility of a decline in the degree of competition.

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During the first Kibaki administration (2002-2007), a movement by the former Mau Mau fighters demanded recognition for the role that they had played in the achievement of independence. They began to demand, also, monetary compensation for past injustices. Why had it taken over 40 years (from independence in 1963) for the former Mau Mau fighters to initiate this movement? What can be observed as the outcome of their movement? To answer these questions, three different historical currents need to be taken into account. These were, respectively, changing trends in the government of Kenya, progress in historical research into the actual circumstances of colonial control, and a realization, based on mounting experience, that launching a legal action against Britain could turn out to be a lucrative initiative. This paper concludes that, regardless of the actual purpose of the legal case, neither of their objectives was certain to be achieved. Two inescapable realities remain: the doubts cast on the reputation of the government by its decision to lift the Mau Mau‟s outlaw status – a decision that was widely seen as a latter-day example of the „Kikuyu favouritism‟ policy followed by the first Kibaki administration – and the popular interpretation of the involvement of Leigh Day, well known in Kenya ever since the unexploded bombs case for its success in obtaining substantial compensation payments, as a vehicle for squeezing large amounts of money from the British government for the benefit of the Kikuyu people.

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The European Union has been promoting linguistic diversity for many years as one of its main educational goals. This is an element that facilitates student mobility and student exchanges between different universities and countries and enriches the education of young undergraduates. In particular, a higher degree of competence in the English language is becoming essential for engineers, architects and researchers in general, as English has become the lingua franca that opens up horizons to internationalisation and the transfer of knowledge in today’s world. Many experts point to the Integrated Approach to Contents and Foreign Languages System as being an option that has certain benefits over the traditional method of teaching a second language that is exclusively based on specific subjects. This system advocates teaching the different subjects in the syllabus in a language other than one’s mother tongue, without prioritising knowledge of the language over the subject. This was the idea that in the 2009/10 academic year gave rise to the Second Language Integration Programme (SLI Programme) at the Escuela Arquitectura Técnica in the Universidad Politécnica Madrid (EUATM-UPM), just at the beginning of the tuition of the new Building Engineering Degree, which had been adapted to the European Higher Education Area (EHEA) model. This programme is an interdisciplinary initiative for the set of subjects taught during the semester and is coordinated through the Assistant Director Office for Educational Innovation. The SLI Programme has a dual goal; to familiarise students with the specific English terminology of the subject being taught, and at the same time improve their communication skills in English. A total of thirty lecturers are taking part in the teaching of eleven first year subjects and twelve in the second year, with around 120 students who have voluntarily enrolled in a special group in each semester. During the 2010/2011 academic year the degree of acceptance and the results of the SLI Programme have been monitored. Tools have been designed to aid interdisciplinary coordination and to analyse satisfaction, such as coordination records and surveys. The results currently available refer to the first and second year and are divided into specific aspects of the different subjects involved and into general aspects of the ongoing experience.