No abstract

The West Iberian Margin (WIM) preserves onshore testimonies of three Mesozoic magmatic cycles. In this paper, we present and discuss 40 Ar/ 39 Ar ages and geochemical data for the second cycle, which occurred at least from 148 Ma to 140 Ma, at the Jurassic-Cretaceous transition, during the late stages of an important extensional event associated with the Iberia-Newfoundland rifting. The related lithospheric stretching induced magma genesis by adiabatic decompression. Primitive rocks are fairly alkaline but evolved to SiO 2 -saturated and oversaturated rocks at "high" pressure. Magmas sampled a source of fairly homogenous composition characterized by Sr and Nd isotopic compositions (Nd i from +1.6 to +4.2), more enriched than the typical N-MORB source. Magmas were generated at the top of the garnet zone. Considering the thickness of the lithosphere and the geochemical constraints, an origin by melting of a metasomatized domain of the lithosphere is favoured. The composition of these onshore magmas is somewhat distinct from the quasi coeval magmas emplaced offshore, which is interpreted as a result of the less important onshore lithospheric stretching, leading to lower degrees of partial melting. This favoured the contribution of lithospheric metasomatized domains to onshore magmas. Rocks intruded two sectors of the Lusitanian Basin separated by the Nazaré Fault and characterized by distinct subsidence rates during the Jurassic. The fact that the rocks to the north of the Nazaré Fault are significantly more evolved indicates the more important development of magma chambers in the north, suggesting distinct thermal profiles for those two sectors. Such magma chambers enabled the "high-pressure" fractionation necessary to drive magma compositions from Ne-normative to SiO 2 -saturated and -over-saturated. The rocks cropping out south of the Nazaré fault are clearly less evolved, and its variability is mostly due to different partial melting events. Some rocks present evidence of post- A C C E P T E D M A N U S C R I P T ACCEPTED MANUSCRIPT3 magmatic processes involving neighbouring Jurassic evaporite materials, leading to an increase in the Na 2 O content and 87 Sr/ 86 Sr ratio.

This paper analyses the efficiency of individual retail stores belonging to a Portuguese multi-market hypermarket retailing chain, employing data envelopment analysis (DEA). The use of DEA for the analysis of intra-chain comparative store efficiency can be of value in examining the competitiveness of the chain as a whole. Competitiveness should be based on benchmarking the retail outlets which compose the chain. We conclude from our research that some outlets are at the frontier of best practice, while others are inefficient. Managerial implications arising from the study are considered.

Esse trabalho visa discutir a importncia dos relacionamentos estratgicos de negcios de forma cooperativa, pois se tm tornado um importante antecedente de sucesso nos negcios. Estudos mostram que alianas e parcerias possuem um importante papel na moldagem das vantagens competitivas baseadas em recursos da empresa. Para a concretizao dos objetivos propostos nesse estudo, iniciou-se uma investigao em duas redes imobilirias e adotou-se como pilar metodolgico, a tipologia qualitativa de investigao, por fornecer a melhor adequao ao fenmeno observado. Foram utilizados como instrumento: entrevista semi-estruturada, pesquisa bibliogrfica e observao no-participante. Conclui-se que os relacionamentos se mostraram importantes e estratgicos para empresas que esto atuando em formato de redes. Como conseqncia direta, o acesso aos parceiros e aos recursos que esses possuem pode ser considerado, como o mais estratgico dos pontos analisados. Como limite metodolgico deve ser citado o fato de a pesquisa ser de cunho qualitativo. Os resultados tm pouco campo de generalizao se comparados a pesquisas quantitativas. A maior implicao prtica que se pode advir dessa pesquisa levar aos gestores que esto participando de uma rede, a importncia estratgica que os relacionamentos possuem. Os gestores devero considerar, dentro da formulao das suas estratgias, o desenvolvimento e a manuteno de relacionamentos para: terem acessos aos parceiros da rede e aos recursos que esses possuem; e construrem uma posio forte dentro da rede de forma a poderem influenciar outros parceiros.DOI: 10.5585/remark.v9i2.2174