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Baffin Bay hosts the largest and most productive of the Arctic polynyas: the North Water (NOW). Despite its significance and active role in water mass formation, the history of the NOW beyond the observational era remains poorly known. We reconcile the previously unassessed relationship between long-term NOW dynamics and ocean conditions by applying a multiproxy approach to two marine sediment cores from the region that, together, span the Holocene. Declining influence of Atlantic Water in the NOW is coeval with regional records that indicate the inception of a strong and recurrent polynya from ~ 4400 yrs BP, in line with Neoglacial cooling. During warmer Holocene intervals such as the Roman Warm Period, a weaker NOW is evident, and its reduced capacity to influence bottom ocean conditions facilitated northward penetration of Atlantic Water. Future warming in the Arctic may have negative consequences for this vital biological oasis, with the potential knock-on effect of warm water penetration further north and intensified melt of the marine-terminating glaciers that flank the coast of northwest Greenland.

La sebkha de l'Ariana est une lagune fermée qui fait partie des zones humides du Maghreb. Elle a une superficie de 30 à 35 km2 et est située sur la bordure nord-ouest du golfe de Tunis, au sud de l'oued Medjerda. Vers 190 000 ans BP, elle a été occupée par la mer Méditerranée. Actuellement, elle en est séparée par un cordon littoral. Ce dernier s'est mis en place lors du comblement d'un golfe peu profond sous l'impulsion d'importantes quantités d'alluvions déposées par le fleuve de la Medjerda sur sa plaine deltaïque dont elle fait partie. Cette étude de l'évolution et de la dynamique de la sebkha de l'Ariana, ainsi que des changements environnementaux récents qui gouvernent la sédimentation, est basée sur une approche sédimentologique, paléontologique et isotopique. Six carottes longues de 20 m à 50 m, prélevées dans les dépôts alluviaux de la sebkha, ont fait l'objet d'une étude détaillée qui a permis de suivre la répartition spatio-temporelle du stock sédimentaire - formé essentiellement de silts argileux vaseux à la base, surmontés de sables - et de mettre en évidence des associations faunistiques particulières traduisant des modifications environnementales : environne­ment marin (Pléistocène moyen), lagune ouverte (Holocène) et sebkha (Actuel). Cette évolution d'un milieu marin franc vers un environnement typi­quement évaporitique (sebkha) pratiquement azoï'que, est probablement en rapport avec le changement climatique quaternaire. The Sebkha of Ariana, covering 30 to 35 km2 is a closed lagoon, located south of the Medjerda and considered to be part of the Maghreb humid zones. It belongs to the Mediterranean coast and is positioned on the N-W margin of the Gulf of Tunis. The Sebkha is situated on Quaternary lowland resulting from the filling-up of a shallow gulf by alluvial deposits sourced from the Medjerda delta. Historically at - 190 ka, the lagoon was related to the sea but at the present time, being bunged up from the sea-side by a beach barrier, is shaped to the sediments of the Madjerda low valley. The study of the evolution and the dynamics of the Ariana Sebkha as well as the recent environmental changes which have governed sedimentation are based on a sedimentological, palaeontological and isotopic approach. For that, six cores (from 20 to 50 m) were realised from four sites of the Sebkha respectively. Furthermore, correlations between the different cores throughout the lagoon have allowed the reconstruction of the spatial-temporal distribution of sedi­ments. The granulometric analyses revealed an alluvial sedimentation mainly composed of argillaceous silts at the base, becoming sandy towards the top. On the other hand, the benthonic fauna determinations of the six cores show a distinct evolution from an open-marine environment to a typically lagoonal environment where fauna are rare to absent. Moreover, the palaeontological study yielded particular benthonic foraminifera associations suggesting important palaeonvironmental changes which in turn are related to Quaternary climatic changes.

La Formación Tubará en el Arroyo Piedras (169 m) es dividida en tres segmentos, interpretados como producto de la sedimentación en ambientes marino marginales relacionados con la evolución del paleo-delta del río Magdalena durante el Plioceno Temprano: El segmento inferior, es interpretado como resultado de sedimentación siliciclástica en una llanura aluvial/deltaica; el segmento intermedio, como el resultado de sedimentación lagunar y/o en pantanos costeros y el superior, como la transición entre ambientes de anteplaya/bahía y frente de playa superior, caracterizados por una considerable reducción en el aporte de material terrígeno, al parecer, producto de una migración del paleo-delta del río Magdalena., 96 p., The Tubara Formation in the Arroyo Piedras Creek (169 m) is divided in three segments, that are interpreted as the result deposition on marginal marine environments related to the Early Pliocene evolution of the Magdalena river paleo-delta: The lower segment is interpreted as the result of siliciclastic sedimentation in an alluvial/deltaic plain; the intermediate as the result of sedimentation on a lagoon and/or coastal swamps, and the upper in the foreshore/bay – upper shoreface transition, characterized by a considerable terrigenous input decrease, maybe, originated by a migration in the Magdalena paleo-delta river system., Contenido parcial: Contexto Geológico -- Descripción de litofacies -- Distribución estratigráfica de los Foraminíferos -- Significado paleoambiental de las asociaciones de foraminíferos -- Contexto geológico durante la acumulación de la Formación Tubará.

Benthic foraminifera were investigated from 20 grab samples collected from a large marine embayment, Disko Bugt, along the west Greenland margin. Agglutinated and calcareous foraminifera were found throughout Disko Bugt, with agglutinated species dominating 19 out of the 20 samples. The most common species are Adercotryma glomerata, Spiroplectammina biformis, Textularia earlandi, Cribrosto- moides crassimargo and Reophax fusiformis. Six faunal assemblage zones were identified from cluster analysis and detrended correspondence analysis. The relationship between the foraminifera and environmental variables was investigated using canonical correspondence analysis. From this analysis, bottom water salinity and water depth were identified as the most important environmental variables explaining the fora- miniferal assemblages. This result suggests water mass characteristics in Disko Bugt are an important control on the benthic foraminiferal assemblage zones. Where the warm and saline West Greenland Current water mass impinges on the seafloor, the assemblage is dominated by A. glomerata, T. earlandi, R. fusiformis and Reophax pilulifer. Sites with the cold, lower salinity Polar Water mass at the seafloor are dominated by S. biformis and A. glomerata, with common Cuneata arctica and C. crassimargo. In shallow locations with a relatively warm and low salinity surface water mass and coarse sediments the fauna is dominated by Cibicides lobatulus. In similar hydrographic locations with fine-grained sediments a mixed faunal assemblage dominated by Ammos- calaria pseudospiralis and Eggerella advena is found.

We investigated the distribution and presence of theratological specimens in benthonic foraminiferal assemblages along the coast of the Sorrento Peninsula (southern part of the Tyrrhenian margin). Thirtyeight samples were analyzed from surficial shallow water sediments and a total of 97 benthonic foraminiferal species, belonging to 21 families, were identified along the shelf zone (between -6 and -102 m). Calcareous forms were dominant and equal to 82.6 % of the total population, whereas agglutinated forms characterised only 17.4 % of the total assemblage. A small number of specimens, related to eleven species, Connemarella rudis, Quinqueloculina disparilis, Q. milletti, Q. seminulumsp., Adelosina pulchella, Peneroplis pertusus, Asterigerinata mamilla, Elphidium crispum, Cibicides lobatulus and Planorbulina mediterranensis, from six calcareous families and one agglutinated familyten distinct types of morphological deformities of their tests. These include: (1) aberrant chamber shape and lack of sculpture; (2) aberrant shape of last chamber; (3) abnormal growth of last chamber; (4) double aperture; (5) wrong coiling; (6) anomalous protuberance; (7) tendency to siamese twin; (8) high spire giving a spiroconvex test, (9) additional chambers and (10) poor development. Morphological deformities are independent of latitude, taxonomic position, mode of life, and feeding strategy of foraminifera. They can occur within the range of natural variability of a givgiven environmental conditions. Benthonic foraminifera can reflect human-induced environmental perturbation and can be used as bioindicators for monitoring coastal pollution.

Se analizaron 13 muestras superficiales ("core-tops") de sedimentos de la Cuenca de Panamá, Pacífico Colombiano, de las que se extrajeron los foraminíferos bentónicos de la fracción >150mm. A partir del contenido microfaunal de las muestras superficiales se divide la Cuenca de Panamá en tres zonas: (1) región eutrófica norte (~8º y 5,5ºN), caracterizada por una alta concentración del flujo de carbono orgánico al fondo oceánico, sedimentos oxigenados, e influencia de las surgencias de la Cuenca de Panamá y Domo de Costa Rica, (2) región mesotrófica media (~5,5 y 2ºN), caracterizada por bajos valores en el flujo de carbono orgánico al fondo oceánico, sedimentos oxigenados, influencia terrígena y fluctuaciones de los sistemas de surgencia presentes en la cuenca, y (3) región eutrófica sur (al sur de ~2ºN), caracterizada por la mayor concentración de flujo de carbono orgánico al fondo oceánico, con contenidos de oxígeno bajos pero sin alcanzar condiciones anóxicas, e influencia de la Divergencia Ecuatorial. Thirteen deep-sea samples (core-tops) from the Panama Basin, Colombian Pacific, were analysed for benthonic foraminifera in the >150mm size fraction. Based on the microfaunal content, three zones are recognised in the Panama Basin: (1) northern euphrophic region (~8º to 5,5ºN), characterized by a high concentration of organic matter flux to the seafloor, oxygenated sediments, and influence of the Panama Bight and the Costa Rica Dome upwelling systems, (2) mesotrophic region (~5,5 to 2ºN), characterized by low fluxes of organic carbon to the seafloor, oxygenated sediments, terrigenous influence and fluctuations of the upwelling systems of the basin, and (3) southern euphotic region (south of ~2ºN), characterized by a larger organic carbon flux to the seafloor, low oxygen content (disoxia) and influence of the Equatorial Divergence.

The Mahakam delta is a mixed, fluvial and wave dominated delta located in the eastern part of the island of Borneo (the East Kalimantan province of Indonesia). The distribution of benthic fauna in this delta system is influenced by the combined or antagonistic action of three main parameters: fluvial input of fresh water and sediment, tide, and a strong regional north to south drift current. A model of the present-day faunal distribution has been established taking into account the perturbations induced by the tide and by the regional drift current. This model has been extrapolated into the recent past through the study of shallow cores that permit the reconstruction of late Holocene deltaic regression patterns. ––– Recherches micropaléontologiques dans le delta actuel de la Mahakam, Est de l'île de Kalimantan (Indonésie).- Le delta de la Mahakam est un delta mixte, influencé par les apports fluviaux et la marée, localisé sur la partie est de l'île de Bornéo (province indonésienne de Kalimantan Est). La répartition de la microfaune benthique est controlée par l'action parfois combinée, parfois antagoniste de trois principaux facteurs, l'apport fluvial d'eau douce et de sédiments, de la marée et de l'action d'un fort courant balayant du Nord vers le Sud le détroit de Makassar qui sépare l'île de Bornéo de l'archipel des Célèbes. Un modèle de distribution de la microfaune actuelle a été établi prenant en compte les perturbations induites par l'action de la marée et du courant de dérive. Ce modèle de distribution a pu être extrapolé au passé par le biais de l'étude de carottages superficiels illustrant la régression holocène.

Thirteen deep-sea samples (core-tops) from the Panama Basin, Colombian Pacific, were analysed for benthonic foraminifera in the >150µm size fraction. Based on the microfaunal content, three zones are recognised in the Panama Basin: (1) northern euphrophic region (~8° to 5,5°N), characterized by a high concentration of organic matter flux to the seafloor, oxygenated sediments, and influence of the Panama Bight and the Costa Rica Dome upwelling systems, (2) mesotrophic region (~5,5 to 2°N), characterized by low fluxes of organic carbon to the seafloor, oxygenated sediments, terrigenous influence and fluctuations of the upwelling systems of the basin, and (3) southern euphotic region (south of ~2°N), characterized by a larger organic carbon flux to the seafloor, low oxygen content (disoxia) and influence of the Equatorial Divergence.

Planktonic and larger benthonic foraminifers of the Upper Cretaceous (Santonian-Maastrichtian)-Lower Tertiary (Danian) rock units from north, northwest and central Anatolian fore-are basins have been investigated in order to improve the biostratigraphic resolution of this time interval. Total abundance and diversity of planktonic foraminifers vary from rare (the sequence from the Haymana region) to high (the sequences from the Cide, Caycuma, Hanonu and Yenikonak regions) and preservation is poor to moderate due to lithologic variation. First and last appearances of the planktonic foraminifera evaluated as major bio-events have been used to establish the biostratigraphic framework. Planktonic foraminiferal zonation from bottom to top of the succession consists of zones defined by Dicarinella concavata, Dicarinella asymetrica, Globotruncanita elevata, Globotruncana, ventricosa, Radotruncana calcarata, Globotruncanella havanensis, Globotruncana aegyptiaca, Gansserina gansseri, Abathomphalus mayaroensis and Morozovella pseudobulloides. Ten Orbitoides and Lepidorbitoides species have been identified. The different phylogenetic development stages of Orbitoides and Lepidorbitoides populations and other larger benthonic foraminifers, Pseudosiderolites vidali, Siderolites calcitrapoides, Siderolites denticulatus, Omphalocylus macroporus, Cideina sozerii, Hellenocyclina beotica, and Clypeorbis mamillata have been calibrated with the planktonic foraminiferal zonation established in the same successions. Hence, an integrated zonational scheme composed of planktonic foraminifers and larger benthonic foraminifers has allowed a detailed stratigraphy of these successions to be erected.

WOS: 000085050300006, Planktonic and larger benthonic foraminifers of the Upper Cretaceous (Santonian-Maastrichtian)-Lower Tertiary (Danian) rock units from north, northwest and central Anatolian fore-are basins have been investigated in order to improve the biostratigraphic resolution of this time interval. Total abundance and diversity of planktonic foraminifers vary from rare (the sequence from the Haymana region) to high (the sequences from the Cide, Caycuma, Hanonu and Yenikonak regions) and preservation is poor to moderate due to lithologic variation. First and last appearances of the planktonic foraminifera evaluated as major bio-events have been used to establish the biostratigraphic framework. Planktonic foraminiferal zonation from bottom to top of the succession consists of zones defined by Dicarinella concavata, Dicarinella asymetrica, Globotruncanita elevata, Globotruncana, ventricosa, Radotruncana calcarata, Globotruncanella havanensis, Globotruncana aegyptiaca, Gansserina gansseri, Abathomphalus mayaroensis and Morozovella pseudobulloides. Ten Orbitoides and Lepidorbitoides species have been identified. The different phylogenetic development stages of Orbitoides and Lepidorbitoides populations and other larger benthonic foraminifers, Pseudosiderolites vidali, Siderolites calcitrapoides, Siderolites denticulatus, Omphalocylus macroporus, Cideina sozerii, Hellenocyclina beotica, and Clypeorbis mamillata have been calibrated with the planktonic foraminiferal zonation established in the same successions. Hence, an integrated zonational scheme composed of planktonic foraminifers and larger benthonic foraminifers has allowed a detailed stratigraphy of these successions to be erected. Copyright (C) 1999 John Wiley & Sons, Ltd.

The carbonate Transgressive Systems Tracts included within the two Depositional Sequences from the "Muschelkalk" of Pyrenees (DS2.17, Late Anisian - Early Ladinian and DS2.12, Late Ladinian-Carnian pro parte) contain assemblages of alpine-type benthonic Foraminifera and palynomorphs. The first sequence is pointed by the local presence of Meandrospira gr. pusilla-dinarica which was only recognized in the Spanish Pyrenees, not studied herein. The second one includes a diversified microfauna which is relatively constant along the totality of the range, Spanish Pyrenees included. The corresponding assemblage, illustrated for the first time in this part of Pyrenees to the East of the Garonne, is characterized by numerous lnvolutinacea (Aulotortus praegaschei, Triadodiscus eomesozoicus and Lamelliconus multispirus) and also by Endothyridae (Endothyranella wirzi), Duostominidae and Glomospirillinae. This assemblage is similar to the synchronous one which was recently quoted in the Catalonian Pyrenees, Balearic Islands (Minorca) and Corsica.

Three of the Triassic depositional sequences outcropping in Corsica, in the Balagne Autochthon (Ladinian-? Carnian sequence at 228 Ma) and in the Prepiemontaise Zone (Lower Rhaetian (R1), at 225 Ma, and Upper Rhaetian-Hettangian (R2), at 211 Ma, sequences) contain, particularly in their transgressive limestones, two benthonic Foraminifera associations which are well known on the future European margin of the Tethys. The earliest assemblage, assigned to Ladinian-? Carnian, principally consists of Involutinacea such as Triadodiscus eomesozoicus and Aulotortus praegaschei ; the latest (Rhaetian) includes various taxa such as Aulotortus ftiedli, Gandinella falsofriedli, Agathammina ? inconstans and A. austroalpina. The analysis of the Foraminifera, their comparison with micropaleontological associations from other localities of a North Tethyan type and the detailed study of the palaeogeographical distribution and of the palaeoecology of Agathammina ? inconstans and Gandinella falsofriedli which characterize the two microfaunal associations, have been carried out.

Bathymétrie repartition of the benthic Foraminifera on the continental shelf. From the data obtained by several workers, it is possible to propose some general patterns of the present foraminiferal bathymétrie distribution. Four main faunal breaks are evidenced at 50-70 m, 90-100 m, 100-120 m and 180-200 m depth. The most important factors are the seasonnal thermic variations and the light intensity. The 50-70 m boundary is the most conspicuous, its location appears to be linked with the thermocline. At this level we note the disapearance of a lot of species thus considered as eurythermal. This species are also, despite few exceptions, adapted to high light intensities and often contain symbiotic algae. Above this limit, the population is rich in forms with porcelaneous tests. Miliolidae, Peneroplidae, Elphidiidae, Discorbidae, Rotaliidae, Cibicididae and, locally, Amphisteginidae, Nummulitidae are frequent. Their percentages vary from a biotope to another and are controlled by several ecological parameters other than depth (salinity, turbulence, grain size of the sediment, vegetation etc...). The lower limits are marked by successives appearances of more and more stenothermal taxa, the most of which extending down to the upper slope. The proportion of the hyaline tests increases to the detriment of porcelaneous ones. Bathyal agglutinated forms are pre sent below 150-180 m. These criteria may be used with caution for paleoecologieal interpretations. The 50-70 m boundary is the most conspicuous, its location appears to be linked with the thermocline. At this level we note the disapearance of a lot of species thus considered as eurythermal. This species are also, despite few exceptions, adapted to high light intensities and often contain symbiotic algae. Above this limit, the population is rich in forms with porcelaneous tests. Miliolidae, Peneroplidae, Elphidiidae, Discorbidae, Rotaliidae, Cibicididae and, locally, Amphisteginidae, Nummulitidae are frequent. Their percentages vary from a biotope to another and are controlled by several ecological parameters other than depth (salinity, turbulence, grain size of the sediment, vegetation etc...). The lower limits are marked by successives appearances of more and more stenothermal taxa, the most of which extending down to the upper slope. The proportion of the hyaline tests increases to the detriment of porcelaneous ones. Bathyal agglutinated forms are pre sent below 150-180 m. These criteria may be used with caution for paleoecologieal interpretations., A partir des données obtenues par de nombreux auteurs, il a été possible de dégager quelques tendances générales concernant la répartition bathymétrique des foraminifères actuels sur la plate-forme continentale. Quatre coupures fauniques majeures sont observées à 50-70 m, 90-100 m, 120-150 m, 180-200 m. Les facteurs principaux de la zonation sont l'écart thermique saisonnier et l'intensité lumineuse. La coupure à 50-70 m est la plus nette, sa profondeur dépend de celle de la thermocline. A ce niveau on note la disparition d'un stock faunistique considéré comme eurytherme. Ces formes tolèrent, en outre, pour la plupart, les fortes luminosités et hébergent souvent des algues symbiotiques. Au-dessus de cette limite, la population est riche en formes à test porcelané. Miliolidae, Peneroplidae, Elphidiidae, Discorbidae, Rotaliidae, Cibicididae et, localement, Amphisteginidae, Nummultitidae sont abondants. Leurs pourcentages varient dans les différents biotopes en fonction de paramètres écologiques locaux (salinité, turbulence, granulométrie du sédiment, végétation, etc...). Les coupures suivantes correspondent à des apparitions successives de formes de plus en plus sténothermes dont la plupart se rencontrent jusqu'au sommet de la pente bathyale. La proportion des tests hyalins augmente aux dépends des tests porcelanés. Des formes arénacées bathyales sont présentes à partir de 180 m. Ces critères peuvent être utilisés, avec précaution, pour les interprétations paléoécologiques., Blanc-Vernet Laure. Répartition bathymétrique des Foraminifères benthiques sur la plate-forme continentale. In: Géologie Méditerranéenne. Tome 15, numéro 1, 1988. Indicateurs bathymétriques biologiques des milieux actuels de la marge continentale. pp. 5-12.

A continuous core in the marine deposits of the Bosq d'Aubigny formation (Manche department, France) has been examined from a palynological and a micropaleontological (Foraminifera) point of view. A relative chronostratigraphical datation, based on palynological data, has been proposed : two pollen-zones were distinguished and correlated with the end of the Tiglian A and early Tiglian В of the Netherlands. Foraminifera belong to benthonic species and show the difficulties involved to establish a common chronostratigraphical scale between synchronous marine and continental events, when both occur in the coastal environment., L'étude d'un forage au Bosq d'Aubigny (Manche) effectué dans des sédiments marins a été examinée du point de vue palynologique et micropaléontologique (Foraminifères). Une datation chronostratigraphique relative a été proposée par la palynologie : deux zones polliniques sont distinguées, pouvant être mises en corrélation avec la fin du Tiglien A et le début du Tiglien В des Pays-Bas. Les Foraminifères sont des espèces benthiques de faciès littoral de type Pliocène et ne varient pas qualitativement tout au long du forage. Les résultats ont permis de mesurer la difficulté à établir une échelle chronologique commune entre des éléments synchrones marins et continentaux dans un domaine marin peu éloigné du littoral., Clet-Pellerin Martine, Le Calvez Yolande, Pareyn Claude. Le Tiglien dans le Cotentin. Essai de datation par les pollens et les Foraminifères d'un forage effectué au Bosq d'Aubigny (Manche) / Tiglian in Normandy. Tentative dating by pollen and Foraminifera from a borehole at Bosq d'Aubigny (Manche). In: Sciences Géologiques. Bulletin, tome 38, n°1, 1985. Palynologie. pp. 67-71.