Atrasos vários levam a que seja eu a subscrever este texto que se quer de afirmação face à dinâmica de um conjunto de docentes e de um departamento; contudo esta edição deve muito ao interesse que o Prof. José Ernesto Mesquita Rodrigues, como Reitor, sempre manifestou pela publicação de trabalhos produzidos pela Universidade de Aveiro. (...)

Precession in the rotation of the inner core seems to induce a precession of the geomagnetic field with a period of about 3.3X10 10 rad/s. This value corresponds to an elongation of 3.2X10 6 of the prolate spheroid of the inner core. Friction due to the liquid outer core seems compatible with a viscosity of the order of 10 4 Pa.s (10 5 poises).On the other hand, gravitational pulsations could be an adequate mechanism for producing magnetics reversals.

Current methodologies are refered to, from geological mapping up to exploration by drilling. So are described geological guides, as well as successful geophysical and geochemical methods and techniques, for each one of the several potential mineralized belts. Massive sulphide deposits, manganese, copper, lead, zinc, iron, tin, and tungsten deposits occur in different geological environments within those belts (translated by the journal).

The effect of mineralisers such as: Mg (NO3)2, 6H20, Ca (N03)2, 4H20, Mg (C3H302)2, 4H20, Ca (C3H302)2, 1/2h20, MgCI2, 6H20 e CaCI2, 6H20, fixed both in the external and in the internal surfaces of kaolinites crystals appears to be very effective on the anticipation of both nucleation and growth of the high temperature metaphases and phases. Hydrazine hydrate intercalation has been used for the opening up of kaolinite structural layers.

Magnetization of volcanic rocks is expected to be related to the magnetic susceptibility and to the amount of magnetic minerals. The distribution of these properties is somewhat erratic. Wich seems to be due to deuteric alterations, during the cooling of lava flows.

To obtain the total or parcial weathering curve of a rock and to quantify it in the time is subject that can avoid problems in certain types of civil engineering works or can lead to avoid or to use certain types of rock materials. in this paper one outlines an attempt to get it with experimental data obtained in a gneissie rock and one presents the weatherability quantification.

A Pyrrhotite-hearing calc-silicate rock from Odivelas dam (Beja igneous complex) is briefly described. A comparision is made with similar lithofacies knoen in Portel and Alvito mining districts, leading to some speculations on a much wider scale. The Cambrian period could represent a sort of trabsition between the two great Cadomian and Hereynian cycles, testifying the end of acredtion between the Ossa-Morena and the Central-Iberian terranes. The Mombeja mafic complex in Beja massif probably represents a Silurian-Devonian oceanic crust that can be correlated with one: it does not seem necessary to postulate a Petite Sole - Cordoue transform fault in order to link Western Europe to Southern Appalaches. The Mombeja-Acebuches ophiolitic complex represents an Early-Middle Paleozoic oceanic lithosphere. A primitive Beja-Aracena-Castilblanco massif is not a bad candidate to the Carboniferous limit between the Ossa-Morena and South-POrtuguese zones: the picture ois obscured by the lack of a global, unified study of the entire massif, wich has been dismembered by many wrench-faults, mainy ENE-WSW.