Submarine landform assemblages and sedimentary processes related to glacier surging in Kongsfjorden, Svalbard

High-resolution swath-bathymetry data from inner Kongsfjorden, Svalbard, reveal characteristic landform assemblages formed during and after surges of tidewater glaciers, and provide new insights into the dynamics of surging glaciers. Glacier front oscillations and overriding related to surge activity lead to the formation of overridden moraines, glacial lineations of two types, terminal moraines, associated debris lobes and De Geer moraines. In contrast to submarine landform assemblages from other Svalbard fjords, the occurrence of two kinds of glacial lineations and the presence of De Geer moraines suggest variability in the landforms produced by surge-type tidewater glaciers. All the landforms in inner Kongsfjorden were deposited during the last c. 150 years. Lithological and acoustic data from the innermost fjord reveal that suspension settling from meltwater plumes as well as ice rafting are dominant sedimentary processes in the fjord, leading to the deposition of stratified glacimarine muds with variable numbers of clasts. Reworking of sediments by glacier surging results in the deposition of sediment lobes containing massive glacimarine muds. Two sediment cores reveal minimum sediment accumulation rates related to the Kongsvegen surge from 1948; these were 30 cm a-1 approximately 2.5 km beyond the glacier front shortly after surge termination, and rapidly dropped to an average rate of 1.8 cm a-1 in ∼1950, during glacier retreat.

Contribuição para o conhecimento da geologia do Grupo das Beiras (CXG) na região do Caramulo-Buçaco, Portugal Central

O presente trabalho ocupa-se do estudo do Complexo Xisto-Grauváquico ante-ordovícico (Grupo das Beiras) na região do Caramulo-Buçaco (centro de Portugal). Em termos geológicos, a área estudada pertence à Zona Centro Ibérica e encontra-se limitada a N pelo granito do Caramulo, a S pela bacia meso-cenozóica de Arganil, a W pelo sinclinal paleozóico do Buçaco e pela bacia meso-cenozóica ocidental portuguesa e a E pelo sinclinal paleozóico de Arganil e pelo plutonito granítico de Tábua-Santa Comba Dão; no seio da área estudada encontra-se a bacia meso-cenozóica de Mortágua. Com base nas características litológicas e estruturais distinguem-se no Complexo Xisto Grauváquico 4 grandes conjuntos litológicos concordantes entre si, designados de Unidades I, II, III e IV, que se desenvolvem da base para o topo de N para S. A Unidade I situa-se a N da região. O seu limite inferior é desconhecido, e o superior posiciona-se no último conjunto arenoso com potência decamétrica. É constituída por xistos cinzentos e negros com intercalações de arenitos de espessura não superior a 100 metros e de extensão lateral quilométrica. Apresenta uma espessura mínima de 1000 m. A Unidade II apresenta consideravelmente menor proporção de material arenoso intercalado entre os pelitos comparativamente à unidade inferior. É caracterizada por apresentar um predomínio de material silto-argiloso e escassos níveis arenosos com potência não superior à dezena de metros e escassa continuidade lateral. Cartograficamente esta unidade constitui uma franja alargada de orientação próxima a E-W. Apresenta uma espessura aproximada de 1500 m. A Unidade III é caracterizada pela presença de conjuntos arenosos com extensão lateral quilométrica e espessura de várias dezenas de metros, separados por material silto-argiloso. Os limites inferior e superior estão situados respectivamente abaixo e acima dos principais conjuntos arenosos. Esta unidade apresenta uma espessura máxima estimada na ordem dos 2000 m. A Unidade IV, que é a unidade superior, apresenta um predomínio pelítico, com escassas intercalações de conjuntos arenosos. O seu limite inferior encontra-se no topo do último conjunto arenoso da Unidade III. Apresenta uma espessura mínima de 500 m. As características sedimentológicas das 4 unidades indicam uma sedimentação num ambiente de plataforma externa siliciclástica aberta, com a construção de barras e por vezes sujeita à acção de tempestades, com sucessivos períodos de superficialização e profundização numa bacia de sedimentação bastante subsidente. Em termos estruturais, para além duma deformação pré-ordovícica, que é comprovada pelo forte mergulho e dispersão da orientação dos eixos da 1ª fase varisca e da lineação de intersecção L1, a área estudada foi principalmente afectada pela Orogenia Varisca. A 1ª fase de deformação varisca (F1) gerou dobras com superfícies axiais e xistosidade associada (S1) de direcção WNW-ESE, e forte pendor para NNE. Estas dobras D1 apresentam comprimentos de onda que nunca chegam a ser quilométricos, desenvolvendo-se um grande flanco inverso denunciando a presença de uma antiforma para NNE e uma sinforma para SSW. A 2ª fase de deformação varisca (F2) actuou na parte nordeste da área estudada e é caracterizada por ter gerado dobras de comprimento de onda quilométrico, com planos axiais e xistosidade associada S2 de direcção NW-SE, subverticais ou a pender fortemente para NE. Embora com alguma dispersão, as lineações de intersecção L2 e os eixos das dobras D2 apresentam maioritariamente forte pendor para E. A direcção e tipos de estruturas da F2 sugerem uma correlação com a terceira fase definida em vários pontos da Zona Centro Ibérica e estreitamente relacionada com as intrusões graníticas. Do ponto de vista petrológico, distinguem-se várias rochas sedimentares (pelitos e arenitos) todas elas sujeitas a metamorfismo que não ultrapassa a fácies dos xistos verdes. Dentro das rochas sedimentares mais grosseiras, há a destacar a presença de arenitos vulcânicos cuja composição denuncia, não muito afastados da bacia sedimentar, a presença de aparelhos vulcânicos que estariam em actividade durante a sedimentação. Foram analisadas isotopicamente 27 amostras de metapelitos colhidas em 5 locais diferentes de forma a abranger quase toda a área estudada. Os dados isotópicos de quatro destes locais de amostragem forneceram isócronas Rb-Sr, em rocha total, com valores da ordem dos 400-440 Ma. O granito do Caramulo, datado pela isócrona Rb-Sr em amostras de rocha total, forneceu uma idade de 326±12Ma. As idades modelo Sm-Nd (manto empobrecido) de 5 amostras de metapelitos estão compreendidas entre 1.35 e 1.25 Ga. Este período de tempo pode ser considerado como correspondendo à época de diferenciação mantélica da crusta que deu lugar à maioria das áreas fonte dos metapelitos.

Dendritic Cells for SYN Scan Detection

Artificial immune systems have previously been applied to the problem of intrusion detection. The aim of this research is to develop an intrusion detection system based on the function of Dendritic Cells (DCs). DCs are antigen presenting cells and key to the activation of the human immune system, behaviour which has been abstracted to form the Dendritic Cell Algorithm (DCA). In algorithmic terms, individual DCs perform multi-sensor data fusion, asynchronously correlating the fused data signals with a secondary data stream. Aggregate output of a population of cells is analysed and forms the basis of an anomaly detection system. In this paper the DCA is applied to the detection of outgoing port scans using TCP SYN packets. Results show that detection can be achieved with the DCA, yet some false positives can be encountered when simultaneously scanning and using other network services. Suggestions are made for using adaptive signals to alleviate this uncovered problem.

Analyses of permeability and porosity of sedimentary rocks in terms of unconventional geothermal resource explorations in Poland

Petrophysical investigations are fundamental to natural resource exploration. In order to recognise the geothermal potential of sedimentary rocks in central Poland, 259 samples were collected from prospective deep-lying geothermal reservoirs. Parameters measured include bulk density, skeletal density, effective porosity, permeability, average pore diameter and specific surface. Results indicate that at great depths (mostly > 3,000 m below surface) sedimentary rocks show low values of porosity (mainly less than 5%) and permeability (only sporadically in excess of 1 md). These values call for a petrothermal use of reservoirs, for which an Enhanced Geothermal System (EGS) was developed. Reser- voirs suited for the EGS are Carboniferous and Lower Triassic sandstones in the central part of Poland (Mogilno-Łódź Trough region and a small part of the Kujawy Swell and Fore-Sudetic regions). In addition, Carboniferous limestones in this area are potentially prospective.

Sedimentary archives of climate and sea-level changes during the Holocene in the Rhone prodelta (NW Mediterranean Sea)

A 7.38 m-long sediment core was collected from the eastern part of the Rhone prodelta (NW Mediterranean) at 67 m water depth. A multi-proxy study (sedimentary facies, benthic foraminifera and ostracods, clay mineralogy, and major elements from XRF) provides a multi-decadal to century-scale record of climate and sea-level changes during the Holocene. The early Holocene is marked by alternative silt and clay layers interpreted as distal tempestites deposited in a context of rising sea level. This interval contains shallow infra-littoral benthic meiofauna (e.g. Pontocythere elongata, Elphidium spp., Quinqueloculina lata) and formed between ca. 20 and 50 m water depth. The middle Holocene (ca. 8.3 to 4.5 ka cal. BP), is characterized, at the core site, by a period of sediment starvation (accumulation rate of ca. 0.01 cm yr−1) resulting from the maximum landward shift of the shoreline and the Rhone outlet(s). From a sequence stratigraphic point of view, this condensed interval, about 35 cm-thick, is a Maximum Flooding Surface that can be identified on seismic profiles as the transition between delta retrogradation and delta progradation. It is marked by very distinct changes in all proxy records. Following the stabilization of the global sea level, the late Holocene is marked by the establishment of prodeltaic conditions at the core site, as shown by the lithofacies and by the presence of benthic meiofauna typical of the modern Rhone prodelta (e.g. Valvulineria bradyana, Cassidulina carinata, Bulimina marginata). Several periods of increased fluvial discharge are also emphasized by the presence of species commonly found in brackish and shallow water environments (e.g. Leptocythere). Some of these periods correspond to the multi-decadal to centennial late Holocene humid periods recognized in Europe (i.e. the 2.8 ka event and the Little Ice Age). Two other periods of increased runoffs at ca. 1.3 and 1.1 ka cal. BP are recognized, and are likely to reflect periods of regional climate deterioration that are observed in the Rhone watershed.

Predicting water permeability in sedimentary rocks from capillary imbibition and pore structure

In this paper, absolute water permeability is estimated from capillary imbibition and pore structure for 15 sedimentary rock types. They present a wide range of petrographic characteristics that provide degrees of connectivity, porosities, pore size distributions, water absorption coefficients by capillarity and water permeabilities. A statistical analysis shows strong correlations among the petrophysical parameters of the studied rocks. Several fundamental properties are fitted into different linear and multiple expressions where water permeability is expressed as a generalized function of the properties. Some practical aspects of these correlations are highlighted in order to use capillary imbibition tests to estimate permeability. The permeability–porosity relation is discussed in the context of the influence of pore connectivity and wettability. As a consequence, we propose a generalized model for permeability that includes information about water fluid rate (water absorption coefficient by capillarity), water properties (density and viscosity), wetting (interfacial tension and contact angle) and pore structure (pore radius and porosity). Its application is examined in terms of the type of pores that contribute to water transport and wettability. The results indicate that the threshold pore radius, in which water percolates through rock, achieves the best description of the pore system. The proposed equation is compared against Carman–Kozeny's and Katz–Thompson's equations. The proposed equation achieves very accurate predictions of the water permeability in the range of 0.01 to 1000 mD.

Genus i ensemble : En intervjustudie om lärares syn på genusuppdraget och dess innebörd för ensembleämnet

Syftet med undersökningen är att med avseende på skolans genusuppdrag studera musiklärares förhållningsätt i ensembleundervisning på gymnasieskolan. För att uppnå detta har kvalitativa, semistrukturerade intervjuer genomförts med lärare i gymnasiekursen ensemble, följt av diskursanalys på transkriberingar av dessa intervjuer. De teoretiska utgångspunkterna är genusteorier och diskursteorier. I resultatet framkommer lärarnas syn på genusbegreppet och genusuppdraget. Bland de genusdiskurser som presenteras finns synen på genus som rutin, som sidoeffekt på annat arbete och som medvetenhet. Gällande elevsyn visar sig diskurser om eleven som platstagare, som normbrytare och vikten av att eleven känner sig som en synbar individ. Slutledningarna, liksom diskussionskapitlet, rör sig kring genusarbetets framgångar, vilka faktorer som kan ha orsakat dessa, och hur arbetet förändrats på skolorna utifrån dessa framgångar. Genomgående har ett individfokus framkommit, där eleverna inte ses som en grupp, utan som enskilda individer, vilka alla måste mötas personligt.

De är mer än sitt framtida yrke : Nio lärares syn på samhällskunskapsundervisningen på yrkesförberedande program

The aim of this study is to examine how teachers view their teaching in civics in vocational programmes. The question formation are: in what extent civic teachers choose to connect the subject with the student’s future profession. Also how the teaching conditions in civics differ between vocational- and pre-university programmes. Lastly the study examines how the teachers experience that their teaching in civics has change since the upper secondary school reform in year 2011. The data was collected through nine interviews with teachers in civic who teach at vocational programmes in Jönköping municipality. The two theories used in the study is the motivational process and Kolbs learning styles. The result show that all the teachers choose to connect their subject with the students’ future profession. But in which extent the teachers choose to do it differs, depending on student’s wishes and the possibility of doing natural connections between the subject and the profession. The terms that differ between vocational- and preuniversity programmes civic lessions are the student’s motivation and how the students learn the best. The biggest change after GY11 is that the teacher’s feel that they have less time but as much material as before. They think it’s harder to do all the different parts of the course because they don’t have enough time. It’s also harder to individualize. The result consistently show that the teaching are most effected by which type of group the students consist of.

Lärares syn på användning av vardagsanknuten matematik : En intervjustudie med fem matematiklärare i årskurs 4-6

Syftet med denna studie har varit att undersöka hur lärare på mellanstadiet ser på användandet av en matematik kopplad till elevers vardag och erfarenheter. Vad betyder det för dem, använder de det i sin undervisning, anser de att det hjälper eller hindrar eleven i sin inlärningsprocess? Undersökningen har varit empirisk och utförts genom intervjuer med fem lärare som alla har behörighet att undervisa i matematik på mellanstadiet. De resultat som framkommit visar att lärare använder sig av en konkretiserad matematik genom att ta hjälp av olika material och koppla uppgifter till de intressen och erfarenheter eleverna bär med sig. En del lärare menar att vissa elever påverkas negativt av det här då det finns vissa delar i en konkretiserad, vardagsanknuten, matematik som gör att de kan uppleva problem och förvirring. Andra lärare menar istället att de märker hur elevernas förståelse ökar och att de tycker att matematik är roligt när de ser hur skolmatematiken kan kopplas samman och relateras till deras vardag och närliggande miljö.

Fyra speciallärares syn på Wendickmodellens användning som en läsutvecklingsmetod : En intervjustudie med speciallärare för grundskolans mellanår.

Syftet med den här undersökningen har varit att undersöka hur fyra speciallärare använder Wendickmodellen i årskurs 4-6 samt att undersöka deras inställning till Wendickmodellen som läsutvecklingsmodell. Undersökningen gjordes genom kvalitativa intervjuer med fyra speciallärare för grundskolans mellanår. Alla dessa har på ett eller annat sätt kommit i kontakt med, och använt sig av, Wendickmodellen, men det är inte alla som använder den i dag. Som teoretisk utgångspunkt har Vygotskijs sociokulturella perspektiv samt Deweys pragmatiska perspektiv använts. Resultatet visar att Wendickmodellens vara eller icke vara inte är vad som avgör om en utlärningssituation är tillfredsställande eller inte, utan snarare att det är det aktiva valet av metod från läraren som avgör. Resultatet visar också att det oftast inte går att använda sig av endast en modell, i alla fyra intervjuer som gjordes blev det tydligt att alla lärare valde att arbeta på olika sätt med sina elever, oavsett om de använde sig av Wendickmodellen eller inte.

Fyra speciallärares syn på Wendickmodellens användning som en läsutvecklingsmetod. : En intervjustudie med speciallärare för grundskolans mellanår.

Syftet med den här undersökningen har varit att undersöka hur fyra speciallärare använder Wendickmodellen i årskurs 4-6 samt att undersöka deras inställning till Wendickmodellen som läsutvecklingsmodell. Undersökningen gjordes genom kvalitativa intervjuer med fyra speciallärare för grundskolans mellanår. Alla dessa har på ett eller annat sätt kommit i kontakt med, och använt sig av, Wendickmodellen, men det är inte alla som använder den i dag. Som teoretisk utgångspunkt har Vygotskijs sociokulturella perspektiv samt Deweys pragmatiska perspektiv använts. Resultatet visar att Wendickmodellens vara eller icke vara inte är vad som avgör om en utlärningssituation är tillfredsställande eller inte, utan snarare att det är det aktiva valet av metod från läraren som avgör. Resultatet visar också att det oftast inte går att använda sig av endast en modell, i alla fyra intervjuer som gjordes blev det tydligt att alla lärare valde att arbeta på olika sätt med sina elever, oavsett om de använde sig av Wendickmodellen eller inte.

Elevers syn på teknikundervisningen : En undersökning av elevers intresse för teknik

Tidigare studier har visat att elevers intresse för teknikundervisningen är låg och därför är det av vikt att forskning bedrivs för att få kunskap om hur skolan kan verka för att väcka intresset för teknik. Syftet med denna studie är att undersöka vad elever är intresserade av att lära sig om på tekniklektionerna, hur de upplever teknikundervisningen och vilken nytta de anser sig ha av teknikkunskapen. Undersökningen genomfördes med både kvalitativ och kvantitativ metod. I undersökningen ingick elever från årskurs 3 och årskurs 5. Totalt besvarade 38 elever en enkät och 5 elevgrupper deltog i fördjupande fokussamtal. I resultatet framkom att majoriteten av eleverna hade en positiv inställning till teknikundervisningen. De visar ett intresse för att lära hur modern teknik, exempelvis datorer, fungerar och anser att det är kunskap som de behöver i vardagslivet. Resultatet visar dock tendenser till att eleverna i årskurs 5 var något mer negativt inställda till teknikundervisningen än eleverna i årskurs 3. Slutsatsen är att eleverna anser att de har nytta av teknikkunskaper för att det finns teknik överallt och de behöver kunna använda denna för att klara sig i samhället. Eleverna har dock svårt att koppla den teknik de möter i skolan till teknik de använder i vardagen.

Varför väljer du bild? : En kvalitativ studie över elevers syn på bildämnet i årskurs 9 och årskurs 1 på gymnasiet

Den här studien syftar till att ta reda på vad elever i årskurs 9 och årskurs 1 på gymnasiet anser om bildämnet. Intresset för de olika åldrarna kommer av att eleverna i årskurs 9 läser bild som ett obligatoriskt ämne medan eleverna i årskurs 1 har gjort ett aktivt val för att läsa bild, och studien önskar att belysa eventuella skillnader i elevernas uppfattningar om bildämnet på grund av detta. Studiens utgångspunkt tar avstamp i det sociokulturella perspektivets syn på lärande, estetiska ämnens betydelse för identitetsskapande, skolans uppdrag genom läroplanernas övergripande syften och mål och elevers egna åsikter om ämnet. Genom dessa perspektiv presenteras bildämnets bakgrund i samhället och tidigare forskning inom området, vilket sedan ställs mot elevernas egna utsagor om bildämnets betydelse. Studien bygger på kvalitativa intervjuer där eleverna har intervjuats i mindre grupper och har diskuterat och reflekterat över bildämnets betydelse. Resultatet visar att eleverna menar att bildämnet har störst betydelse som en kreativ paus bland annan undervisning, men att bildämnet också har en viss betydelse för annat lärande, personligt uttryck och som grundläggande kunskaper i framtiden.

NEW DATA ON THE CHRONOLOGY OF THE VALE DO FORNO SEDIMENTARY SEQUENCE (LOWER TAGUS RIVER TERRACE STAIRCASE) AND ITS RELEVANCE AS FLUVIAL ARCHIVE OF THE MIDDLE PLEISTOCENE IN WESTERN IBERIA

NEW DATA ON THE CHRONOLOGY OF THE VALE DO FORNO SEDIMENTARY SEQUENCE (LOWER TAGUS RIVER TERRACE STAIRCASE) AND ITS RELEVANCE AS FLUVIAL ARCHIVE OF THE MIDDLE PLEISTOCENE IN WESTERN IBERIA Pedro P. Cunha 1, António A. Martins 2, Jan-Pieter Buylaert 3,4, Andrew S. Murray 4, Luis Raposo 5, Paolo Mozzi 6, Martin Stokes 7 1 MARE - Marine and Environmental Sciences Centre, Department of Earth Sciences, University of Coimbra, Portugal: pcunha@dct.uc.pt 2 MARE - Marine and Environmental Sciences Centre, Dep. Geociências, University of Évora, Portugal; aam@uevora.pt 3 Centre for Nuclear Technologies, Technical University of Denmark, Risø Campus, Denmark; jabu@dtu.dk 4 Nordic Laboratory for Luminescence Dating, Aarhus University, Risø DTU, Denmark; anmu@dtu.dk 5 Museu Nacional de Arqueologia, Lisboa, Portugal; 3raposos@sapo.pt 6 Department of Geosciences, University of Padova, Italy; paolo.mozzi@unipd.it 7 School of Geography, Earth and Environmental Sciences, University of Plymouth, UK; m.stokes@plymouth.ac.uk The stratigraphic units that record the evolution of the Tagus River in Portugal (study area between Vila Velha de Ródão and Porto Alto villages; Fig. 1) have different sedimentary characteristics and lithic industries (Cunha et al., 2012): - a culminant sedimentary unit (the ancestral Tagus, before the drainage network entrenchment) – SLD13 (+142 to 262 m above river bed – a.r.b.; with probable age ca. 3,6 to 1,8 Ma), without artefacts; - T1 terrace (+84 to 180 m; ca. 1000? to 900 ka), without artefacts; - T2 terrace (+57 to 150 m; top deposits with a probable age ca. 600 ka), without artefacts; - T3 terrace (+43 to 113 m; ca. 460 to 360? ka), without artefacts; - T4 terrace (+26 to 55 m; ca. 335 a 155 ka), Lower Paleolithic (Acheulian) at basal and middle levels but early Middle Paleolithic at top levels; - T5 terrace (+5 to 34 m; 135 to 73 ka), Middle Paleolithic (Mousterian; Levallois technique); - T6 terrace (+3 to 14 m; 62 to 32 ka), late Middle Paleolithic (late Mousterian); - Carregueira Sands (aeolian sands) and colluvium (+3 a ca. 100 m; 32 to 12 ka), Upper Paleolithic to Epipaleolithic; - alluvial plain (+0 to 8 m; ca. 12 ka to present), Mesolithic and more recent industries. The differences in elevation (a.r.b.) of the several terrace staircases results from differential uplift due to active faults. Longitudinal correlation with the terrace levels indicates that a graded profile ca. 200 km long was achieved during terrace formation periods and a strong control by sea base level was determinant for terrace formation. The Neogene sedimentary units constituted the main source of sediments for the fluvial terraces (Fig. 2). Geomorphological mapping, coupled with lithostratigraphy, sedimentology and luminescence dating (quartz-OSL and K-feldspar post-IRIR290) were used in this study focused on the T4 terrace, which comprises a Lower Gravels (LG) unit and an Upper Sand (US) unit. The thick, coarse and dominantly massive gravels of the LG unit indicate deposition by a coarse bed-load braided river, with strong sediment supply, high gradient and fluvial competence, during conditions of rapidly rising sea level. Luminescence dating only provided minimum ages but it is probable that the LG unit corresponds to the earlier part of the MIS9 (ca. 335 to 325 ka), immediately postdating the incision promoted by the very low sea level (reaching ca. -140 m) during MIS10 (362 to 337 ka), a period of relatively cold climate conditions with weak vegetation cover on slopes and low sea level. Fig. 1. Main Portuguese reaches in which the Tagus River can be divided (Lower Tagus Basin): I – from the Spanish border to Arneiro (a general E–W trend, mainly consisting of polygonal segments); II – from Arneiro to Gavião (NE–SW); III – from Gavião to Arripiado (E–W); IV – from Arripiado to Vila Franca de Xira (NNE-SSW); V – from Vila Franca de Xira to the Atlantic shoreline. The faults considered to be the limit of the referred fluvial sectors are: F1 – Ponsul-Arneiro fault (WSW-ENE); F2 – Gavião fault (NW-SE); F3 – Ortiga fault (NW-SE); F4 – Vila Nova da Barquinha fault (W-E); F5 – Arripiado-Chamusca fault (NNE-SSW). 1 – estuary; 2 – terraces; 3 – faults; 4 – Tagus main channel. The main Iberian drainage basins are also represented (inset). The lower and middle parts of the US unit, comprising an alternation of clayish silts with paleosols and minor sands to the east (flood-plain deposits) and sand deposits to the west (channel belt), have a probable age of ca. 325 to 200 ka. This points to formation during MIS9 to MIS7, under conditions of high to medium sea levels and warm to mild conditions. The upper part of the US unit, dominated by sand facies and with OSL ages of ca. 200 to 154 ka, correlates with the early part of the MIS6. During this period, progradation resulted from climate deterioration and relative depletion of vegetation that promoted enhanced sediment production in the catchment, coupled with initiation of sea-level lowering that increased the longitudinal slope. The Vale do Forno and Vale da Atela archaeological sites (Alpiarça, central Portugal) document the earliest human occupation in the Lower Tagus River, well established in geomorphological and environmental terms, within the Middle Pleistocene. The Lower Palaeolithic sites were found on the T4 terrace (+26 m, a.r.b.). The oldest artefacts previously found in the LG unit, display crude bifacial forms that can be attributed to the Acheulian, with a probable age of ca. 335 to 325 ka. The T4 US unit has archaeological sites stratigraphically documenting successive phases of an evolved Acheulian, that probably date ca. 325 to 300 ka. Notably, these Lower Palaeolithic artisans were able to produce tools with different sophistication levels, simply by applying different strategies: more elaborated reduction sequences in case of bifaces and simple reduction sequences to obtain cleavers. Fig. 2. . Simplified geologic map of the Lower Tagus Cenozoic basin, adapted from the Carta Geológica de Portugal, 1/500000, 1992). The study area (comprising the Vale do Forno and Vale de Atela sites) is located on the more upstream sector of the Lower Tagus River reach IV, between Arripiado and Chamusca villages. 1 – alluvium (Holocene); 2 – terraces (Pleistocene); 3 – sands, silts and gravels (Paleogene to Pliocene); 4 – Sintra Massif (Cretaceous); 5 – limestones, marls, silts and sandstones (Mesozoic); 6 – quartzites (Ordovician); 7 – basement (Proterozoic to Palaeozoic); 8 – main fault. The main Portuguese reaches of the Tagus River are identified (I to V). The VF3 site (Milharós), containing a Final Acheulian industry, with fine and elaborated bifaces) found in a stratigraphic level located between the T4 terrace deposits and a colluvium associated with Late Pleistocene aeolian sands (32 to 12 ka), has an age younger than ca. 154 ka but much older than 32 ka. In the study area, the sedimentary units of the T4 terrace seem to record the river response to sea-level changes and climatically-driven fluctuations in sediment supply. REFERENCES Cunha P. P., Almeida N. A. C., Aubry T., Martins A. A., Murray A. S., Buylaert J.-P., Sohbati R., Raposo L., Rocha L., 2012, Records of human occupation from Pleistocene river terrace and aeolian sediments in the Arneiro depression (Lower Tejo River, central eastern Portugal). Geomorphology, vol. 165-166, pp. 78-90.