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Large volumes of granitoids were emplaced in the Hercynian Central Iberian Zone during the last ductile deformation phase (D3, 300-320 Ma). The biotite-rich granitoids are the most abundant: (1) syn-D3 granodiorites-monzogranites (313-319 Ma) with calc-alkaline and aluminopotassic affinities; (2) late-D3 granodiorites-monzogranites (306-311 Ma), related to subalkaline and aluminopotassic series. These granitoids are associated with coeval gabbro-norite to granodiorite bodies and/or mafic microgranular enclaves. Both granitoids and basic-intermediate rocks show petrological, geochemical and isotopic evidence of interaction between felsic and mafic magmas. The mantle-derived melts, represented by shoshonitic gabbro-norites, were probably derived from an enriched and isotopically homogeneous source (Srl = 0.7049 to 0.7053, E~~ =-2.1 to-2.5). In some synand late-D3 plutons there are evidences of essentially crustal granites, represented by moderately peraluminous monzogranites of aluminopotassic affinity. They have similar Nd model ages (1.4 Ga) but different isotopic compositions (Srl = 0.7089 to 0.7106, cNd =-5.6 to-6.8), revealing a heterogeneous crust. Potential protoliths are metasedimentary (immature sediments) and/or fclsic meta-igneous lower crust materials. Large amounts of hybrid magmas were generated by the interaction of these coeval mantle-and crust-derived liquids, giving rise to slightly peraluminous monzogranites/granodiorites of calc-alkaline and subalkaline affinities, which display more depleted isotopic compositions than the crustal end-members (Sr, = 0.7064 to 0.7085, E~~ =-4.4 to-6.2). Petrogenetic processes involving mingling and/or mixing and fractional crystallization (at variable degrees) in multiple reservoirs are suggested. A major crustal growth event occurred in late-Hercynian times (-305-320 Ma) related to the input of juvenile mantle magmas and leading to the genesis of composite calc-alkaline and subalkaline plutons, largely represented in the Central Iberian Zone.

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The first signs of salt production on the northern coast of Portugal are usually attributed to the Iron Age. However, there is evidence that this activity took place in the region at least between the late 3rd millennium, early 2nd millennium BCE. Data from two archaeological sites are presented and the so-called removable sinks and the sinks excavated in the rock are re-evaluated. Their execution techniques are also discussed. The data set was articulated with the natural and topographic conditions of the coast and the known climatic conditions for the time. They were also articulated with the occupation strategies during the Bronze Age.

Pretende-se com este artigo dar a conhecer os resultados dos trabalhos arqueológicos levados a cabo no monu-mento funerário de Laceiras do Côvo 3, estrutura tumular enquadrável, provavelmente, na Idade do Bronze, localizada na freguesia de Arões, concelho de Vale de Cambra. Este monumento revela-se de particular inte-resse pela policromia intencional na matéria usada na sua construção e pela disposição cuidada dos elementos litológicos do tumulus, em que nada parece estar ao acaso. Tais características sugerem a intenção de manter o espaço dos mortos visível, assim como uma interligação simbólica entre rochas e minerais e as práticas relacio-nadas com a morte. Na linha de Tim Ingold (2000) consideramos, ainda, que a matéria do monumento seria portadora de determinadas propriedades, revelando-se como entidade viva e atuante na construção de sentidos e memórias associadas ao mundo dos mortos.