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Nowadays, there is a growing concern about micronutrient deficits in food products, with agronomic biofortification being considered a mitigation strategy. In this context, as Zn is essential for growth and maintenance of human health, a workflow for the biofortification of grapes from the

Positive tectonic inversion of sedimentary basins has been recognized as one of the primary mechanisms of mountain building and intraplate deformation. Reconstructing the tectonic history of basins is relatively easy for the inversion stage but becomes more difficult for the basinal stage, especially when strong deformation involving cleavage development is associated with the subsequent compressional tectonics. Since tectonic markers for the extensional episodes are not commonly well developed, Anisotropy of Magnetic Susceptibility (AMS) has provided recently a tool for analyzing early stages in the evolution of sedimentary basins, even in the absence of other outcrop-scale mesostructures. Here, we expose and discuss the applicability of magnetic fabrics (by means of AMS) to different types of intra-plate sedimentary basins in the Western Tethys region formed under extensional or transtensional regimes and which underwent different inversion styles (total or partial inversion, with or without cleavage development, forming part of compressional thrust sheets, etc.) owing to specific particular p-T conditions and structural controls. Factors such as lithology, magnetic mineralogy, position within the sedimentary pile and deformation intensity are key to interpret the obtained magnetic fabrics in terms of tectonic evolution. A basin classification is proposed according to inversion styles and magnetic fabrics: Where inversion did not involve cleavage development, magnetic lineation is parallel to the stretching direction corresponding to the extensional stage. The transition between non-cleaved to inversion-related cleaved units is marked by the switch of magnetic lineations from parallel to extension to parallel to the intersection lineation between cleavage and bedding. These relationships are enhanced when extension and compression are roughly coaxial, then favoring the clustering of axes of the magnetic ellipsoid. Even when extreme inversion occurs and the early, extensional fabric is obliterated, magnetic fabrics provide information about the interaction between preferred deformation directions associated with the main stages in basin evolution.

This research was funded by the FCT-Funda??o para a Ci?ncia e a Tecnologia, under grant number SFRH/BD/133777/2017. The first author thanks the FCT-Funda??o para a Ci?ncia e a Tecnologia, under grant number SFRH/BD/133777/2017. The work of J. C. Kullberg was supported by national funds from Fundac?o para a Ci?ncia e a Tecnologia (FCT) through the research unit UID/GEO/04035/2013 (GeoBioTec). Nowadays, the rehabilitation of quarries is a widespread practice. It stems from the most significant environmental concern in the management of non-renewable resources. However, reusing quarry waste in the process of regeneration represents the aspect less prevalent. This procedure results from the non-commercialized material, accumulated in huge piles of waste, that constitute invasive elements of the landscape. Because of the intense industrial activity, the wastes further contribute to the degradation of the sites. The result of the waste abandonment could be reversed if this discarded material is considered as a product in the landscape requalification process. Mixing theoretical concepts with practical examples, this article proposes an application methodology to reuse the waste material in the landscape and architectural domains. This new contribution highlights the importance of considering scrap accumulations as an integral part of the architectural project, filling the existing gap in both architectural and theoretical domains. There is not any similar schematization in the literature and the idea of dealing with the mounds of wastes has been only slightly approached until now. The reached outcomes are demonstrative of the possibility of working with the waste heaps in architecture, creating a solid basis for further investigations not documented yet. publishersversion published

Nowadays, the original image and structure of the territory havebeen permanently changed, by human action, due to the intenseindustrialization. The quarries represent the industrial activity that causes more transmutations in the landscape, modifying it in a more invasive manner. The present research describes a case study in Portugal where is located the highest concentration of marble quarries, flanked by escombreiras, large waste heaps. The work highlights the importance of the waste reuse concept in landscape and architecture, preserving the industrial memory and the identity of the place. The research, through an exhaustive analysis of real examples of quarries rehabilitation, investigates innovative methods to regenerate the Portuguese abandoned landscape. The investigationis expected to prompt the implementation of projects to revitalize the discarded spaces, and toreuse the local waste material for the creation, in situ, of architectonic and landscape elements, and to increase the knowledge on waste reuse procedures. Keywords: Estremoz Anticlinal, marblequarries, waste heaps, waste reuse. Thematic clusters: 2: City and Environment. Topic: Heritage and Cultural Landscape.

The Serra de Sintra is a landmark on the western coast of the Iberian Peninsula, resulting from the intrusion of a complex of alkaline igneous bodies during the upper Cretaceous in a stretched continental passive margin associated with the opening of the Atlantic Ocean. It is a differential erosion mountain standing out on a coastal plateau laid over the Mesozoic sedimentary rocks of the Lusitanian Basin and where the Cenozoic materials are scarce, difficult to date and essentially of continental facies. The morphological evolution of the Serra de Sintra reflects its progressive isostatic rebound and the work of marine erosion combined with Quaternary fluvial retouching.

The Arrabida Breccia is a type of chromatic rock with a very unusual texture, appearing only in the current geographical area of the Natural Park of Arrabida, and thus, its extraction is definitively finished. Due to its petrographic nature, it is very sensitive to weathering, particularly to rainwater. It has had numerous uses for at least 2000 years since the occupation of Iberia by the Romans, and which evolved over time from exterior to interior structures. Since the beginning of the Baroque, it is almost exclusively linked to the interior decorative arts, in polished finishing. Its use had a greater expression linked to the Gothic-Manueline style, closely associated with the epic Portuguese, roughly in the transition in fifteenth to sixteenth centuries particularly during the reign of King Manuel I who would have particular preference for this rock. Its use is characterised by being quite confined, especially as the resource has always been relatively scarce regarding known deposits. Although most of the known applications are located in Portugal, especially in the regions of Setubal and Lisbon, there are also examples of its application in other countries, namely in the Mediterranean Europe and Brazil, largely in buildings classified as of National Interest and in building classified as World Heritage or Architectural Heritage (UNESCO). Due to the above facts, the need to preserve some extracted but not used blocks is also discussed in this work both for the purposes of preservation and restoration of monuments as well as the valuation of the old mines for educational and recreational purposes.

This article aims to act as a general literature review regarding the landscape, analyzing it through a synthesis of the main concepts and processes that have generated, and subsequently developed, the word “Landscape”. It is a versatile theme, because it has always been studied by various disciplines, through different theories, which sometimes even conflict with each other. Through the present text, we understand the importance and the unique value of the landscape, a value that has nowadays been transfigured by the strong industrialization and strong brand of man in the territory. Thus, the first part of the research is, to some extent, a reflection on current issues that are related to the landscape. It is also a tool for integration, including in the definition of “Landscape”, even those heavily humanized, exploited, degraded, abandoned, and residual; the so-called “Drosscape”, “Friche”, and “Terrain Vague”. The solution is not to negatively interpret these types of scenarios, but rather to enhance them as they are, filled with potential and creativity. This concept is achieved by means of an operation of recycling or reuse of waste, which is capable of germinating new life cycles within the “dead nature” of our increasingly cemented territories.

A global view of the Mesozoic-Cenozoic geodynamic evolution of the Iberian microplate is necessary to determine the role of inherited Variscan structures in the configuration of the Alpine Cycle. Furthermore, it is important to reconstruct the extensional Mesozoic geometries of the Iberian margins, presently inverted during the Cenozoic compression. We discuss briefly in this chapter, thanks to a large number of innovative scientific studies, the evolution of the Iberian microplate and of its margins, and the geology of Iberia mountain ranges and foreland basins: the Betic-Rif system along the southern plate boundary and the Pyrenees-Bay of Biscay along the northern Iberian plate boundary. In addition, the renewed interest in the role of Triassic salt tectonics both during extension and compression is also discussed.

The West and SouthWest Margins of Iberia started their formation as intra-continental rifts during initial break up of Pangea in Triassic times. The tectono-stratigraphic record of the Algarve, Alentejo and Lusitanian basins and their offshore prolongation documents the syn-rift, post-rift and passive margin phases of the rifting process as well as three magmatic cycles of tholeiite to alkaline affinities. Although the Ocean-Continent Transition has been investigated using deep ocean drilling, seismics, gravimetry and magnetics its nature and location are still matters of debate. The tectonic inheritance of the Paleozoic Orogeny had great influence in the geometry of the rift basins and development of the Neo-Tethys and Atlantic Oceans intersection. Salt tectonics strongly controlled both syn-rift and post-rift basin tectonics and led to the formation of an allochthonous salt nappe in the Algarve Basin.

19 pages, 7 figures, The Alpine orogeny is well recorded onshore and offshore by tectonic inversion of the Mesozoic rift basins. Large scale linear seamounts (more than 250 km long and with up to 5 km of uplift) involving oceanic and continental lithosphere were carried on top of thrusts, such as the Gorringe seamount and the Estremadura Spur in the SouthWest and West Iberia Margin, respectively. The SouthWest Iberia Margin also recorded the westward migration of the Gibraltar Oceanic slab as the westwards propagation of the Neo-Tethys subduction. Rotation of the tectonic compression from NW-SE to WNW-ESE in Pliocene times caused the development of large scale dextral wrench faults as the present day Africa-Iberia plate boundary. Neotectonics of this plate boundary caused large to mega-scale destructive earthquakes and tsunamis

During the Triassic, Iberia and western North Africa displayed a unique situation in relation with the Central and North Atlantic opening and westward expansion of the Tethys. Unravelling the stretching direction in Triassic deposits of the studied area can help in our understanding of this scenario. The tectonic setting is characterized by localized basins with strong thickness variations greatly influenced by previous post-Variscan mechanical discontinuities. In this work, we revise and compile magnetic fabric data from eight Triassic depocentres in terms of defining the stretching direction (i.e. magnetic lineation), resulting from extensional deformation of this period. Data show the importance of the opening of the Atlantic rift as the leading process during the Triassic. Dextral transtension can explain the deflection of the extensional direction observed in most studied depocentres that is caused by the activity of previous major oblique faults.

Low dietary intake of Ca in humans has been epidemiologically linked to various diseases, which can have serious health consequences over time. Accordingly, the development of an agronomic itinerary for Ca biofortification of Rocha pears and the assessment of physicochemical deviations prompted this study. Two orchards with contrasting soil and water characteristics were selected, characterized through orthophotomaping and, during fruits development, leaves were sprayed twice with Ca(NO3)2 (0.1, 0.3 and 0.6 kg ha - 1) or CaCl2 (0.4, 0.8 and 1.6 kg ha - 1), followed by pulverization only with CaCl2 (first once with 4 kg ha - 1 and then four times with 8 kg ha - 1). During fruits development net photosynthesis, stomatal conductance, transpiration rates, instantaneous and water use efficiency, only showed minor deviations, which indicated that the threshold of toxicity was not surpassed. Calcium contents varied during fruits development and at harvesting the average biofortification index varied between 47 %–63 % and 24 %–59 % in each of the orchards. Besides, the equatorial region of the fruits showed for all treatments (substantially in Ca treated samples) higher Ca contents in the epidermal and in the central regions. Fresh and heat-treated fruits (in a thermomix at 90 ◦C, during 10 min) biofortified with Ca only revealed minor differences and the sensory acceptability did not vary markedly. It is concluded that, although prevailing a heterogeneous distribution of Ca in fruit tissues, high indexes of biofortification in Rocha pears can be prompt in the orchards, without substantial physicochemical changes. Accordingly, agronomic biofortification with Ca can be used as a strategy for benefiting consumer’s health info:eu-repo/semantics/publishedVersion

This study aimed to assess the efficiency of Ca enrichment in tubers of three genotypes of Solanum tuberosum L., through foliar spraying with CaCl2 and Ca(NO3)2 solutions. In this context, soil heterogeneity of three potato-growing fields, as well as the implications of Ca accumulation among tissues and some quality parameters were assessed. Three potato varieties (Agria, Picasso and Rossi) were grown in three production fields and during the life cycle, four pulverizations with calcium chloride (3 and 6 kg ha&minus, 1) or calcium nitrate (0.5, 2 and 4 kg ha&minus, 1) were applied. For screening the potential phytotoxicity, using Agria as a test system, the potential synthesis of photoassimilates was determined, and it was found that after the 3rd Ca application, leaf gas exchanges were moderately (net photosynthesis), to strongly (stomatal conductance) affected, although without impact on Ca accumulation in tubers. At harvest, the average Ca biofortification index varied between 5&ndash, 40%, 40&ndash, 35% and 4.3&ndash, 13% in Agria, Picasso and Rossi, respectively. Moreover, the equatorial region of the tubers in general showed that Ca accumulation prevailed in the epidermis and, in some cases, in inner areas of the potato tubers. Biofortified tubers with Ca also showed some significant changes in total soluble solids and colorimetric parameters. It is concluded that Ca enrichment of potato tubers through foliar spraying complemented the xylem mass flow of Ca from roots, through phloem redistribution. Both fertilizers showed similar efficiency, but Rossi revealed a lower index of Ca accumulation, eventually due to different metabolic characteristics. Although affected by Ca enrichment, potato tubers maintained a high quality for industrial processing.

The geometry and emplacement of the ~ 96 km2, Late Cretaceous Sintra Igneous complex (SIC, ca. 80 Ma) into the West Iberian passive margin is presented, based on structural data, gravimetric modeling, and magnetic fabrics. A granite laccolith (~ 76 km2, Division of Marine Geology and Georesources, Instituto Português do Mar e da Atmosfera, Portugal, Unidad de Zaragoza, Instituto Geológico y Minero de España, España, Departamento de Geodinámica, Universidad del País Vasco, España, Centro de Investigação em Ciência e Engenharia Geológica, Universidade Nova de Lisboa, Portugal, Departamento de Geologia, Universidade de Lisboa, Portugal, Geotransfer, Universidad de Zaragoza, España, Departamento de Geociências, Universidade de Aveiro, Portugal

At the beginning of the Alpine cycle, the breakup of Pangea lead to the early stages of the North Atlantic opening. In the western Iberian sector of the European margin, the Lusitanian basin starts to evolve bordered eastwards by inherited reliefs from the late episodes of the Variscan orogeny. The base unit, the Silves Group, considered not earlier than the Carnian, is mainly siliciclastic and predominantly formed by arcosarenites to feldspar litarenites, coarse to very coarse-grained (wackes) and pebbly, where the sediment architecture denotes organizations in continental (Conraria, Penela and Castelo Viegas Formations) environments. A first marine episode (Isocyprina Beds of Pereiros Fm.) marks a significant change within the sedimentary record; the uppermost part corresponds to intertidal transitional environments (sabkha). New and detailed field work of sedimentological and structural nature that has been carried out in recent exposures from the type-region of Coimbra-Penela enabled us to make significant observations and to improve data collection. This allowed a full reinterpretation of the paleotectonic and paleogeographical conditions under which the Silves Group and, consequently, the eastern border of the Lusitanian basin, evolved. This study carried out in the type-region also allowed a better understanding of its sequential organization. All units are unconformity bounded by strong influxes of coarse siliciclastics from the Iberian meseta. One of those unconformities (D2b) is an angular unconformity with cartographic expression. Tectonic reconstructions were possible to make after a detailed structural analysis of normal synsedimentary faults. Regional comparisons with Eastern Iberian basins that evolved since Permian times are also discussed. We conclude that the lower red siliciclastic units are older than has been considered until now. Those units were formed in a previous tensional stress pattern of tardi-Variscan affinities, related to megashear dextral kinematics of Permian-Triassic age. We propose that units below D2b unconformity can record a Proto-Lusitanian basin; the Lusitanian basin is younger and evolved mainly after the Triassic-Jurassic limit (Castelo Viegas Fm.) within an E-W extensional context related to Atlantic type basins.

The prediction of rockfall trajectories below a rock cliff is essential in susceptibility, hazard and risk maps, particularity close to populated areas. The Monte da Lua hill area in Portugal, a tourist destination close to the historic city of Sintra (UNESCO World Heritage), is a typical granite boulder chaos landscape where from time to time rockfalls occur, the last such event having occurred on 29 January 2002. This area is therefore suitable to develop a rockfall study in order to provide hazard and risk maps a basis for mitigation measures. A preliminary investigation of the area leads to the identification of 188 potentially dangerous boulders. Detailed locations and geotechnical characteristics in terms of geometry, strength and context were sampled for each boulder. Digital elevations at 1 × 1 m resolution, known rockfall trajectory and building locations are provided in a GIS project for the study together with the spatial database of boulder characteristics. The modelling approach was conducted in two steps: (1) discrimination of the boulders in terms of static and dynamic mobility behaviour with multivariate analysis; (2) stochastic simulation of rockfall trajectories. The rockfall trajectory algorithm proposed is straightforward and is only dependent on elevation data, initial location of boulders and a friction angle. Due to the slope of the area, it assumes that rockfall is always of the rolling or sliding type. The friction angle was calibrated on the basis of the rockfall travel distance recorded on 29 January 2002 and generates simulated “realistic” trajectories. A smaller friction angle increases all simulated trajectories, leading to more “pessimistic” scenarios. The combined analysis of trajectories and potential damage to buildings and discrimination in terms of static and dynamic behaviour provides a final table in which all 188 sampled boulders are classified in one of the five risk grades.

A well preserved bioeroded surface occurs at the unconformity separating Cretaceous limestones and Lower Miocene sediments, outcropping on the western coast of the Peninsula of Setubal (Central West Portugal). The ichnoassemblage present in this bioeroded surface is herein assigned to the Trypanites ichnofacies. The preservation characteristics of the borings reflect several episodes of encrustation/boring and physical erosion. The erosional truncation of bioerosive structures, and the predominant preservation of the largest borings (Gastrochaenolites isp.) in the ichnocoenoses are herein related with repeated phases of bioerosion and physical abrasion occurred during an Early Miocene transgressive pulse. The recognition of this bioeroded transgressive surface also allowed confirming the presence, at that time, of an emergent topographic relief related to salt domes formed earlier, probably already during Palaeogene times.

In the academic year 2012–2013, the Faculty of Science and Technology of the New University of Lisbon (FCT/UNL) conducted a complete revision of its curriculum, with the goal of enhancing the training of its students and increasing the employability of its graduates. In its new profile, the FCT/UNL now includes three distinct teaching periods in an academic year, with the introduction of a five-week period between the two traditional semesters. During this period, several transferrable skills courses are taught in an intensive regimen. In this article, we present the motivations that led to the creation of the course entitled “CTCT — Transferable Skills for Science and Technology”, its incorporation into the new curricular profile of the FCT/UNL, its main objectives, and its syllabus. We also present the methods used in the allocation of students to classes and groups and the feedback from teachers and students participating in the course.

More than one century after its original description by Marsh in 1877, we report in this paper the first uncontroversial evidence of a member of the genus Stegosaurus out of North America. The specimen consists of a partial skeleton from the Upper Jurassic of Portugal, herein considered as Stegosaurus cf. ungulatus. The pres- ence of this plated dinosaur in the upper Kimmeridgian- lower Tithonian Portuguese record and synchronic levels of the Morrison Formation of North America reinforces previous hypothesis of a close relationship between these two areas during the Late Jurassic. This relationship is also supported by geotectonic evidences indicating high proba- bility of an episodic corridor between the Newfoundland and Iberian landmasses. Together, Portuguese Stegosaurus dis- covery and geotectonic inferences could provide a scenario with episodical faunal contact among North Atlantic land- masses during the uppermost Kimmeridgian-lowermost Tithonian (ca. 148-153 Ma ago).

Evidence for three short‐lived compressive episodes of late Carixian, late Callovian–early Oxfordian, and Tithonian‐Berriasian ages that lasted

In this paper, we present the general tectonic framework that conditioned the evolution of the Lusitanian Basin during the Jurassic, when most of the filling of the basin was accumulated. The rifting episodes and the evolution of the basin’s geometry are presented and their close relationship with the main basin-wide unconformities is discussed. The unconformity-bounded sequences are briefly presented as a basis for understanding the evolution of the sedimentary environments. This constitutes the basic geological information to construct the palaeogeographical maps presented in Part II of this paper (this volume).

In this paper we present the first palaeogeographical maps of the Lusitanian Basin during the Jurassic. We also present the methodology used to produce these maps and discuss the close relationship of the temporal and spatial distributions of facies with the sequence of tectonic events in the basin (already discussed in Part I of this study, this volume). One of the main conclusions is that the main bordering N–S-trending faults were the main tectonic structures that conditioned the facies geometry but only during paroxysmal events; during those short intervals, “instant” modifications of the facies geometry occurred. The other main conclusion is that in the time intervals between the paroxysmal events, the structures that conditioned the facies distribution were the main transfer faults, oriented ENE–WSW, and the sedimentary environments gradually rotated from N–S to ENE–WSW.

The upper Oxfordian Arrabida Breccia is a unique lithological type in Portugal and probably in the world because it was formed through several particular geological influences acting simultaneously. The rock is a conglomerate composed of carbonate pebbles of different colours, cemented by a red, ferruginous, clayey carbonate. It is the expression of a fossilized a karst that marks one of the major unconformities of the Lusitanian Basin, which was associated with the early stages of the opening of the North Atlantic. One of the strengths of the candidature of Arrabida for UNESCO’s Mixed World Heritage List is the intimate connection between the natural environment, particularly the landscape (Criterion VII) and the geology and geomorphology (Criterion VIII), and the history and culture of the region and country. The natural occurrences of the Arrabida Breccia (Brecha da Arrabida), the exploration of which ended in 1975 with the creation of the Arrabida Natural Park, are rare and sporadic. The dispersed geographical distribution of outcrops will necessitate the creation of scientific and cultural routes to facilitate visits by the millions of tourists who travel to the Arrabida region each year. The creation of routes in the region is, therefore, one of the objectives of this candidature. In addition, the Brecha da Arrabida conglomerate has been used for ornamental purposes since the late fifteenth century, and was used for the first sculptural and decorative expressions of the so-called Portuguese Late Gothic and Manueline styles, and later during the Baroque because of its colourful varieties. This artistic use of the Brecha da Arrabida, as well as other uses of the material, extends far beyond the actual geographical area of Arrabida. This wider significance provides part of the justification for building a website where users can add information regarding the uses of the Arrabida Breccia in both Portugal and other countries, thereby updating the existing inventory of the material, and constituting a vital component for disseminating knowledge about geology to the public.

Flat-pebble conglomerates have been identified in the Lower Toarcian (Levisoni Zone) carbonates of the Sesimbra region (30 km south of Lisboa, Portugal) and related to submarine mass movements. Their origin is explained through a three-stage model based on the comparative analysis of potential generating mechanisms taking into account timing and type of geodynamic evolution in the Lusitanian Basin: (a) differential lithification of thin carbonate and non-bioturbated horizons embedded within a more argillaceous matrix; (b) disruption by seismic shocks related to active extensional faulting and block tilting; and (c) gravity sliding mixing material resulting from broken lithified horizons. This sequential process originated flat-pebble conglomerates during early Jurassic phases of syn-rift evolution in the southern Lusitanian Basin. q 2001 Elsevier Science B.V. All rights reserved.

Magnetic fabrics in the Lusitanian basin show extreme variability in the orientation of strain axes during part of its Mesozoic extensional stage. A detailed study of Anisotropy of Magnetic Susceptibility (AMS) was done in Triassic and Upper Jurassic units in the onshore part of the basin. In the Triassic samples, the magnetic lineation shows a dominant NW–SE orientation, perpendicular to the main normal fault set and also to the extension directions inferred from the analysis of brittle mesostructures. For the Late Jurassic period, the AMS analysis indicates a dominant N–S to NE–SW extension. Moreover, these main directions are complicated by perpendicular solutions co-existing in the same sites. Comparison with syn-sedimentary faults reveals the difficulty in interpreting AMS data in these settings, although magnetic stability for the obtained solutions can be tracked through different mineralogical composition for the sampled rocks. Interpretation of the obtained fabrics through a Triassic radial extension regime is consistent with axes switching and local re-orientation of strain axes close to major normal faults related to the opening of the Northern Atlantic during the Jurassic, Unidad de Zaragoza, Instituto Geológico y Minero de España, España, Departamento de Ciências da Terra, Universidade Nova de Lisboa, Portugal, Instituto Pirenaico de Ecología, España, Departamento de Ciencias de la Tierra, Universidad de Zaragoza, España, Departamento de Física, Universidad de Burgos, España

GIS APPLICATION FOR INTERACTIVE PROSPECTION OF ENDOKARST. The parameters that affect the development of karst erosion at depth – endokarst - are complex and difficult to understand, due to both their diversity and the difficulty of quantifying the actual contribution of each of them. This work presents a methodology developed in a GIS environment with the aim of identifying the areas in which endokarst is most likely to occur. This case study was conducted within a sample area located to the west of Sesimbra where several of these structures have been identified, with a special emphasis on the caves of Zambujal and Frade. The suggested model is based on the interactive combinatory analysis of the dependent variables according to skillful criteria, taking into account their relative contributions to the development of endokarst. One of the main goals of this study is the development of an interactive software application enabling to test and evaluate the relative importance of the selected parameters. A decision was made to use a simple classification of the supervised or skillful type, in which the variables, their inter-relations and their relations with the surrounding areas are conveyed under the summarised form of a ranking of their relative relevance, as measured by their expected contribution to karstification. The output of the model consists of a set of maps that indicate the likelihood of the occurrence of endokarst at any given point. The hierarchical relevance of each variable, the selection of larger or smaller buffer areas for fractures and fracture intersections, the choice of appropriate variables and their subdivision into a number of categories allow for scrutiny to be applied at a series of different levels, rendering possible the skillful calibration of the results to all the places where the predominant geology is of the carbonate type. At the same time, the comparative analysis of these results provides an excellent opportunity for us to understand the parameters that most contribute to the formation of endokarst. The suggested model was tested interactively and the latter analysis and validation of the results allowed for the positive identification of the appropriate sequence of those variables that most affect the formation of endokarst, Finisterra, vol. 38 n.º 76 (2003)

The Alpine foreland in Portugal was deformed by compressional tectonism during the Miocene. In the NNE-SSW oriented Lusitanian Basin, most folds and thrusts in the Meso-Cenozoic cover are oriented ENE-WSW, parallel to the Alpine front in the Betic Cordillera, and verge towards the north-northwest and south-southeast. The thrusts are connected by lateral ramps: most of these are oriented NNE-SSW to N-S and show sinistral movement, and some are transpressional. The lateral ramps result from reactivation of older extensional faults related to crustal thinning of the continental margin. In the E-W oriented Algarve Basin a simpler basin inversion occurred, with older E-W normal faults reactivated as essentially pure thrusts. In both basins Alpine structures formed above decollements in the Hettangian evaporite-clastic complex. Variscan basement was also deformed by ENE-WSW reverse faults during Miocene time. The similarity in orientation and style of the basement structures to those in the cover suggests that they also occurred by detachment, but their larger scale indicates that the detachment is deep and involves much of the crust. Thus, we interpret the Central Cordillera, in which basement rocks are thrust over Miocene sediments on both sides, as a “pop-up” of crustal scale, elevated above downward-flattening faults that dip towards each other and merge into a single deep detachment. Alpine structures in the Iberian foreland are therefore similar in structural style to those of the Appalachian and Laramide forelands of North America and the Alpine foreland of northwest Europe.

The onshore sector of theWest Iberian Margin (WIM) was the locus of several cycles of magmatic activity during the Mesozoic, the most voluminous of which was of alkaline nature and occurred between 70 and 100 Ma. This cycle took place in a post-rift environment, during the 35 counter-clockwise rotation of Iberia and initiation of the alpine compression. It includes the subvolcanic complexes of Sintra, Sines, and Monchique, the volcanic complex of Lisbon and several other minor intrusions, covering an area of approximately 325 km2. Previous cycles were tholeiitic and transitional in nature, occuring around 200 Ma and 130–135 Ma, respectively. New LA-ICP-MS U-Pb, 40Ar/39Ar, K-Ar and Rb-Sr ages on several intrusions distributed along the onshore WIM are presented, which combined with reviously published data allows us to constrain the duration of the Late Cretaceous alkaline cycle to circa 22 Ma (94–72 Ma) and define two pulses of magmatic activity. The first one (94–88 Ma) occurred during the opening of the Bay of Biscay and consequent rotation of Iberia and clusters above N38 200 . The second pulse (75–72 Ma) has a wider geographical distribution, from N37 to N39 . This final pulse occurred during the initial stages of the Alpine orogeny in Iberia that led to the formation of the Pyrenees and Betics and to tectonic inversion of the Mesozoic basins. Isotope and trace element geochemistry point to a sublithospheric source for the alkaline magmatism that clearly distinguishes it from the previous cycles which had an important lithospheric mantle component. Also, it allows the discrimination between the two different alkaline pulses in terms of trace element abundance and residual mantle minerology. It is speculated that these differences might be the result of distinct magma ascent rates due to either more or less favourable tectonic settings that avoided or allowed the interaction with metasomatized lithosphere and equilibration with K rich minerals like amphibole and/or phlogopite.