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Studies of the upper 447 m of the DEEP site sediment succession from central Lake Ohrid, Balkan Peninsula, North Macedonia and Albania provided important insights into the regional climate history and evolutionary dynamics since permanent lacustrine conditions established at 1.36 million years ago (Ma). This paper focuses on the entire 584-m-long DEEP sediment succession and a comparison to a 197-m-long sediment succession from the Pestani site ~5 km to the east in the lake, where drilling ended close to the bedrock, to unravel the earliest history of Lake Ohrid and its basin development. 26Al/10Be dating of clasts from the base of the DEEP sediment succession implies that the sedimentation in the modern basin started at c. 2 Ma. Geophysical, sedimentological and micropalaeontological data allow for chronological information to be transposed from the DEEP to the Pestani succession. Fluvial conditions, slack water conditions, peat formation and/or complete desiccation prevailed at the DEEP and Pestani sites until 1.36 and 1.21 Ma, respectively, before a larger lake extended over both sites. Activation of karst aquifers to the east probably by tectonic activity and a potential existence of neighbouring Lake Prespa supported filling of Lake Ohrid. The lake deepened gradually, with a relatively constant vertical displacement rate of ~0.2 mm a−1 between the central and the eastern lateral basin and with greater water depth presumably during interglacial periods. Although the dynamic environment characterized by local processes and the fragmentary chronology of the basal sediment successions from both sites hamper palaeoclimatic significance prior to the existence of a larger lake, the new data provide an unprecedented and detailed picture of the geodynamic evolution of the basin and lake that is Europe’s presumed oldest extant freshwater lake.

ilustraciones Mediante el uso del ensayo de penetración con cono y medición de presión de poros (CPTu), es posible el cálculo de múltiples geoparámetros útiles para la caracterización del suelo y el diseño geotécnico, la mayoría de los parámetros geotécnicos que pueden obtenerse del ensayo provienen de correlaciones empíricas que requieren calibración con otras técnicas de exploración del subsuelo y ensayos de laboratorio. El trabajo plasmado en este documento presenta la caracterización geotécnica del depósito lacustre de Bogotá y los resultados de la calibración de los principales parámetros de interés geotécnico obtenidos del piezocono, que ostentan un alto grado de incertidumbre. Se realizó la calibración de las ecuaciones existentes o la generación de nuevos modelos que permitan la definición de parámetros de clasificación del suelo como el peso unitario total y parámetros asociados a la resistencia del material del depósito, su historia de esfuerzos y rigidez, como la resistencia al corte no drenado, la relación de sobre consolidación (RSC) y la velocidad de onda de corte. Los resultados se obtuvieron mediante análisis estadísticos y matemáticos a partir de la recopilación de información de campañas exploratorias localizadas en la zona de estudio, para un total de 140 perforaciones mecánicas, 87 piezoconos con longitudes de hasta 50 m y los ensayos de campo y laboratorio asociados. Los modelos matemáticos obtenidos en la investigación ofrecen mejores resultados con respecto a las ecuaciones actuales más comunes. Para la resistencia al corte no drenado se presenta una zonificación del Nkt que depende de la profundidad y la ubicación en el depósito. Para parámetros como la RSC y la velocidad de onda de corte se encontraron valores del coeficiente de determinación (R2) iguales a 0.61 y 0.95, respectivamente. En cuanto al peso unitario total y el ángulo de fricción interna del suelo, los resultados se ajustan a la tendencia general de los ensayos de laboratorio de referencia, con valores medios de 13 kN/m3 y 21°, respectivamente. (Texto tomado de la fuente) It is possible to calculate multiple parameters useful for soil characterization and geotechnical design using the Piezocone Penetration Test (CPTu). Most of the geotechnical parameters that can be estimated from the CPTu data are obtained using empirical correlations that require calibration and verification with other subsoil exploration techniques and laboratory tests. This document presents a geotechnical characterization of the Bogotá lacustrine deposit and the results of the calibration of the main parameters of geotechnical interest, which has a high degree of uncertainty. Calibration of existing equations or generation of new models was performed in order to define the soil classification parameters such as unit weight, and parameters associated with the deposit resistance, stress history and stiffness, such as undrained shear strength, overconsolidation ratio (OCR) and shear wave velocity. Results were obtained through statistical and mathematical analysis. Data of soil exploration campaigns distributed throughout the study area that included 140 mechanical perforations and 87 CPTu to depths of up to 50 m was compiled for the calibration. Mathematic models obtained during the research, provide better results regarding the current equations. For the undrained shear strength, a Nkt zonification is presented, which depends on the depth and location of the deposit. Parameters such as the OCR and the shear wave velocity show values of the coefficient of determination (R2) of 0.61 and 0.95, respectively. In terms of the unit weight and the intern friction angle, the results follow a general trend concerning to the laboratory test, with mean values of 13 kN/m3 and 21° respectively. (Texto tomado de la fuente) Maestría Magíster en Ingeniería Civil - Geotecnia Modelación y Análisis en Geotecnia

A 601 m long sedimentary sequence was drilled in Lake Acigöl, located in the lakes region of SW Anatolia, near the Denizli travertine from which the oldest hominin of Turkey was unearthed. Among all dating methods applied to the sedimentary sequence, paleomagnetism, through the recognition of geomagnetic chrons, was the most successful and led to a quasi linear age model, with the 601 m long sedimentary record covering the last 2.3 Ma. An attempt to use the atmospherically deposited 10Be as a dating method was not very successful but provides interesting clues on this new method. Long-term lake level changes are depicted through lithological variations, in particular the carbonates and evaporites abundance. This change could be influenced by both long term cooling during the last 2 Ma and tectonic activity, which may in particular be responsible for a maximum water depth at around 1.8 Ma. Despite active tectonic influence, the sedimentary facies description and the magnetic susceptibility record (cleaned from tephra intervals) show that climate fluctuations (i.e., glacial-interglacial alternations) are likely recorded in the sedimentary succession, with warm periods marked by enhanced carbonate precipitation and cold and dry periods characterized by more detrital input linked to reduced vegetation cover and consequently more erosion in the catchment area. Preliminary pollen data, used to interpret magnetic susceptibility fluctuations, show that an average dry and open landscape prevailed around Acigöl lake during the whole record. © 2019, 114Y723 Agricultural Marketing Service, AMS Agence Nationale de la Recherche, ANR Aligarh Muslim University, AMU Centre National de la Recherche Scientifique, CNRS, This research was funded by TUBITAK-CNRS bilateral cooperation with the grant number of 114Y723 during 2015–2017. The funds by 1) the ECCOREV Research Federation (OSU PYTHEAS, CNRS, AMU) for the project “ACIGOL”, 2) the Labex OT-MED (OSU PYTHEAS, CNRS, AMU) for the project BILAT, 3) and the projet EPICA (INSU 2018; Programme Tellus-INTERVIE) were received during 2017–2018. We thank the Wissenschaftliche Gesellschaft Freiburg im Breisgau for additional funding. We acknowledge the ALKIM Company for permitting us access and sampling to the core with special gratitude to Mr Hüseyin Ünlü (MSc) who was the director of ALKIM Company in Acigöl during the sampling and Mr. Mahmut Eser (MSc), the manager of the exploitation and Mr. Ünal Arık, present director of the company. The ASTER AMS national facility (CEREGE, Aix en Provence) is supported by the program INSU/CNRS INTERVIE, the ANR through the “Projets thématiques d'excellence” program for the “Equipements d'excellence” ASTER-CEREGE action and IRD. We thank S. Choy and L. Gacem for their help in the 9 Be measurements using the AAS of the LN2C (CEREGE). The data are archived at https://dx.doi.org/10.1594/PANGAEA.907658 . Appendix A, This research was funded by TUBITAK-CNRS bilateral cooperation with the grant number of 114Y723 during 2015?2017. The funds by 1) the ECCOREV Research Federation (OSU PYTHEAS, CNRS, AMU) for the project ?ACIGOL?, 2) the Labex OT-MED (OSU PYTHEAS, CNRS, AMU) for the project BILAT, 3) and the projet EPICA (INSU 2018; Programme Tellus-INTERVIE) were received during 2017?2018. We thank the Wissenschaftliche Gesellschaft Freiburg im Breisgau for additional funding. We acknowledge the ALKIM Company for permitting us access and sampling to the core with special gratitude to Mr H?seyin ?nl? (MSc) who was the director of ALKIM Company in Acig?l during the sampling and Mr. Mahmut Eser (MSc), the manager of the exploitation and Mr. ?nal Ar?k, present director of the company. The ASTER AMS national facility (CEREGE, Aix en Provence) is supported by the program INSU/CNRS INTERVIE, the ANR through the ?Projets th?matiques d'excellence? program for the ?Equipements d'excellence? ASTER-CEREGE action and IRD. We thank S. Choy and L. Gacem for their help in the 9Be measurements using the AAS of the LN2C (CEREGE). The data are archived at https://dx.doi.org/10.1594/PANGAEA.907658.

The Bahçeköy coal field, which is the subject of this study, is located in the Gölbaşı Neogene basin in the south of Ankara (central Turkey). The pre-Neogene basement rocks located in the west and south of the basin are mostly composed of Permo-Triassic carbonate rocks, Cretaceous ophiolites, and Eocene turbidites. The coals in the Bahçeköy area are observed in the lower part of the Pliocene lacustrine sedimentary sequence which fills the basin. In the western part of the basin, the basalts and the lacustrine sediments, which contain coal, show intrusive contact relations in the lateral direction, during the Pliocene period, with the effect of the volcanism developing at the same time with sedimentation. Diatomite intercalations were formed at the upper parts of the lacustrine sequence which reached 12 m. The widespread observation of diatomites is quite important and it implies that the silicon-rich solutions associated with volcanism are involved in the lacustrine environment. The thickness of the economic coal level in Bahçeköy area varies between 4 and 12 m. According to these thicknesses, the total coal reserves calculated for the Bahçeköy area reach up to 16 million tons. The obtained drilling data shows that Bahçeköy coals exhibit rapid thickness and quality changes in the lateral direction. The chemical analyses point out these coals have average calorific value ranging from 7762 to 12,413 kJ/kg and ash content ranging from 44 to 65%. © 2019, Saudi Society for Geosciences.

Pollen analysis was done on lacustrine sedimentary sequences dated by micromammals as late Pliocene–early Pleistocene that outcrop in two Neogene graben basins from SW Turkey. This study shows vegetation changes from steppe-like to more forested environments, very similar to the cyclic oscillations related to late Pleistocene glacial–interglacial climate changes. Artemisia was abundant during cold–arid periods, indicating that this species was already widespread in this area during the latest Pliocene and the beginning of the Pleistocene. A review of pollen records from Anatolia agrees with this study, suggesting that the spreading of this arid species occurred during a major climatic change: the beginning of the first glaciations and probably a change in seasonality towards summer aridity. Artemisia temporarily disappeared from the region during warm–wet periods and thus we suggest that glacial–interglacial-type oscillations already occurred in the area during the late Pliocene–early Pleistocene.

The major and trace element component of 48 recent sediment samples in three distinct intervals (0–10, 10–20, and 20–30 cm) from Lake Acıgöl is described to present the current contamination levels and grift structure of detrital and evaporate mineral patterns of these sediments in this extreme saline environment. The spatial and vertical concentrations of major oxides were not uniform in the each subsurface interval. However, similar spatial distribution patterns were observed for some major element couples, due mainly to the detrital and evaporate origin of these elements. A sequential extraction procedure including five distinct steps was also performed to determine the different bonds of trace elements in the < 60-µ particulate size of recent sediments. Eleven trace elements (Ni, Fe, Cd, Pb, Cu, Zn, As, Co, Cr, Al and Mn) in nine surface and subsurface sediment samples were analyzed with chemical partitioning procedures to determine the trace element percentage loads in these different sequential extraction phases. The obtained accuracy values via comparison of the bulk trace metal loads with the total loads of five extraction steps were satisfying for the Ni, Fe, Cd, Zn, and Co. While, bulk analysis results of the Cu, Ni, and V elements have good correlation with total organic matter, organic fraction of sequential extraction characterized by Cu, As, Cd, and Pb. Shallow Lake Acıgöl sediment is characteristic with two different redox layer a) oxic upper level sediments, where trace metals are mobilized, b) reduced subsurface level, where the trace metals are precipitated. © 2018, Springer International Publishing AG, part of Springer Nature.

The purpose of this thesis was to study the South Atlantic rift system in Congo by focusing on (1) the dynamic of the upstream paleoreliefs (rift shoulders), (2) the stratigraphic architecture and (3) sediment routing of the pre to syn-rift sedimentary infilling. Detailed field mapping allows to characterize the geometry of the incised valleys, sedimentary environments of thier sediment infilling and to discuss the geodynamic implications of these incised valleys in terms of rift dynamic and control of sedimentary systems. These incised valleys were cut through the Precambrian Mayombe basement by alluvial processes shaping pediments during the stretching period of the rift and filled with middle Aptian siliciclastic sediments of the Chéla formation. The sediment filling consists of flood-generated sublacustrine gravity flow deposits interbedded with organic-rich lacustrine shales, overlying unconformably the basement. These deposits are organized into an overall transgressive depositional sequence, characterized by stacked of elementary fining upward facies sequences. Detailled facies analysis of cores permits to determine the sedimentary environments of the Pointe-Noire, Pointe-Indienne and Chéla Formation, developed during the hyper-extended (sag) rift phase. The middle Barremian Pointe-Noire Formation consists of organic-rich shale-prone deep-lacustrine fan facies intertonguing locally with shallow-water platform carbonate facies and gravity-flow resedimented carbonate facies of the Toca Member that were deposited in an anoxic deep-lake. The Late Barremian–early Aptian Pointe-Indienne Formation is characterized by facies heterogeneity. This Formation consists of sand-rich sublacustrine-fan gravity facies of Mengo member overlain by storm influenced mixed siliciclastic-carbonate ramp facies (Argiles vertes Member) passing upward to deltaic facies of Tchibota member. The middle Aptian Chéla Formation represents a widespread transgressive unit, characterized by lateral and vertical changes in facies and a variety of depositional environnements. It is made up of interbedded coarse-grained alluvial bedload facies and sub-lacustrine gravity facies at the base, overlain by lacustrine-marine mixed bay facies passing upward to sabkha facies, which in turn are capped by evaporites of the Loémé Formation. The sebkha facies records the late middle Aptian marine transgression on the Congo basin prior to the deposition of Upper Aptian evaporites of Loémé Formation. Well-log stratigraphic correlations permit subdivision of the middle Barremian to middle Aptian syn-hyper-extended rift-related deposits into three major depositional sequences that display retrogradation, progradation, and retrogradation stacking pattern, respectively. Detrital zircon and apatite provenance analyses provide a better understanding of sediment routing systems of the pre to syn-rift infilling, and paleorelief and tectonic evolutions during the Early Cretaceous times. The results show changes in sediment provenances and two different source areas. The Berriasian-Valanginian Pre-rift sediments of the Vandji Formation were derived from multiple and relatively distant source areas, located either in the South America and southern of Africa plate, thus supporting the existence of large intracratonic basin prior to the rifting, fed by prominent large-scale drainage system. located toward the southwest. In contrast to the Pre-rift sediments, the Barremian syn-stretched rift sediments of the Djeno Formation and the Aptian syn- hyper-extended rift sediments of the Chela Formation were derived from adjacent Precambrian Mayombe belt that underwent phases of tectonic uplift during the rifting. Consequently, this implies an abrupt change in sediment provenance and relief between the pre-rift phase and the Syn-rift phase and indicate the persistence of local sources, i.e. from rift shoulders, from the stretching rift phase to the hyper-extended (sag) rift phase., Le propos de cette thèse est d’étudier le rift de l’Atlantique sud au Congo, en se focalisant sur (1) la dynamique des reliefs amont du rift (les épaulements de rift), (2) l’architecture stratigraphique du remplissage sédimentaire et (3) le routage sédimentaire ante- à syn-rift. L’etude de terrain a permis de reconstituer la géométrie des paléovallées, le cadre sédimentaire et stratigraphique du remplissage sédimentaire et de discuter des implications géodynamiques de ces paleovalleys en termes de dynamique du rift et de contrôle des systèmes sédimentaires. Ces paléovallées ont été incisées dans le substratum précambrien du Mayombe par des rivières alluviales pendant la phase d'étirement du rifting et remplies par des sédiments d’âge Aptien moyen de la Formation de Chéla. Le remplissage sédimentaire de ces paléovallées consiste en des faciès gravitaires sousaquatiques interdigités dans les argiles lacustres riches en matière organique, recouvrant en discordante le socle Précambrien du Mayombe. Ces depôts s'organisent en une séquence transgressive, caractérisée par l’empilement des séquences élémentaires de type finning-up . L’analyse sédimentologique de carottes a permis de caractériser les environnements de dépôts des Formations de Pointe-Noire, Pointe-indienne et de Chéla, correspondant à la phase d’hyperextension (sag) de l’evolution du rift. La Formation de Pointe-Noire d’âge Barrémien moyen est constituée des faciès gravitaires de cônes sous-lacustres profonds à dominance argileux et riches en matière organique dans lesquels s’intercalent localement des faciès carbonatés de plate-forme peu profonde et gravitaires resédimentés du membre de Toca, accumulés au cours d'une importante transgression associée à un évènement anoxique général. La Formation de Pointe-indienne d’âge Barrémien supérieur à Aptien inferieur est caracterisée par variations latérales et verticales de faciès. Elle comprend des faciès gravitaires gréso-argileux (membre Mengo) de cônes sous-lacustres profonds, surmontés par des faciès mixtes silicoclastiques et carbonatés de rampe interne à moyenne dominée par des vagues de tempêtes (Membre des Argiles vertes) passant progressivement vers le haut à des faciès deltaïques de Tchibota. La formation de Chéla d’âge Aptien moyen se caractérise par des variations latérales et verticales de faciès. Elle comprend des faciès sous-aquatiques de delta alluvionnaire passant latéralement aux faciès gravitaires sous-lacustres, suivi par des faciès de baies mixtes lacustres -marine, surmontés par des faciès de sabkha (membre Vembo) recourvets par les evaorites de Loémé. Les facies de sebkha au sommet de la Formation de Chéla témoignent d’une incursion marine avant la mise en place des évaporites. Les corrélations stratigraphiques entre puits ont permis de subdiviser la succession sédimentaire de la phase d’hyper-extension (sag) en trois principales séquences de dépôt montrant respectivement des tendances rétrogradante, progradante et rétrogradante. La datation des zircons et apatites détritiques a permis de reconstituer le routage sédimentaire ante- à syn-rift et l’évolution de reliefs en amant du rift. Les résultats montrent des changements spatio-temporels de sources de sediments et deux régions de provenance de sédiments. Les sédiments ante-rift (Formation de Vandji) d’age Berriasien proviennent des sources lointaines, confirmant l’existence d’un système pre-rift – et donc d’un bassin antérieur au système rift du segment central de l’Atlantique sud, alimenté de l’ouest à sud-ouest par des sources angolaise et brésilienne. Les sédiments syn-rift (Formation de Djéno) d’age Barremien inférieur et Sag (Formation de chéla) d’age Aptien moyen proviennent des sources locales (massif du Mayombe), ce qui implique un changement majeur de sources et de reliefs entre les phases pre-rift et syn-rift et l’existance des reliefs en amont de la faille bordière pendant les phases d’étirement et d’hyper-extension du rift.

Recurrence-plot-based recurrence networks are an approach used to analyze time series using a complex networks theory. In both approaches – recurrence plots and recurrence networks –, a threshold to identify recurrent states is required. The selection of the threshold is important in order to avoid bias of the recurrence network results. In this paper, we propose a novel method to choose a recurrence threshold adaptively. We show a comparison between the constant threshold and adaptive threshold cases to study period–chaos and even period–period transitions in the dynamics of a prototypical model system. This novel method is then used to identify climate transitions from a lake sediment record.

We investigated sediment bacterial metabolism in eight lakes with different inputs of allochthonous and autochthonous organic carbon in south-central Sweden. Sediment bacterial production, mineralization, and biomass were measured seasonally and along a lake depth gradient in lakes with different water and sediment characteristics. Sediment bacterial metabolism was primarily controlled by temperature but also by the quality and origin of organic carbon. Metabolism was positively correlated to measures of autochthonous influence on the sediment organic carbon, but did not show a similar increase with increasing input of allochthonous organic carbon. Hence, in contrast to what is currently known for the water column, increasing terrestrial organic carbon influence does not result in enhanced sediment bacterial metabolism. The role of allochthonous organic carbon as the main driver of sediment bacterial metabolism suggested so far is contrary to our findings. Meio- and macrobenthic invertebrate biomass were, at most, weakly correlated to bacterial metabolism and biomass, suggesting limited control of sediment bacteria by grazing. Bacterial metabolism in boreal lake sediments is constrained by low temperatures and by the recalcitrant nature of the dominant organic carbon, resulting in sediments being an effective sink of organic carbon. � 2012, by the Association for the Sciences of Limnology and Oceanography, Inc.

The Salada Mediana lacustrine sequence, central Ebro Basin, Spain (41 °30'10'N, 0°44'W, 350 m a.s.l.) provides an example of the potential and limitations of saline lake records as palaeoclimate proxies in the semi-arid Mediterranean region. Sedimentary facies analyses, chemical stratigraphy, stable isotopes (δ18O and δ13C) of authigenic carbonates, δ13C values of bulk organic matter and pollen analyses from sediment cores provide paleohydrological and vegetation change reconstructions for the Lateglacial and Late Holocene in the central Ebro basin. A preliminary chronology is based on 210Pb and 14C AMS dates. The lacustrine sequence is composed of three sedimentary Sections. The Lower Section was deposited in a permanent saline to brackish lake. This stage represents the most humid period in the record and it was accompanied by the expansion of temperate trees (particularly Corylus). The Middle Section was deposited in an ephmeral playa-lake complex. Frequent subaerial exposure conditions favour the colonisation of the playa lake floor by Chenopodiaceae during a low water table period. This interval reflects the most arid conditions in the Salada Mediana record, including the current environment. A secondary temperate tree expansion occurred after the maximum aridity period. Aquatic plants and cyanobacterial mats spread in the lake during periods of raised water tables. This paleohydrological and vegetational evolution attests to large changes in effective moisture during the Lateglacial in the semi-arid northeastern Spain. The abundance of Corylus during the Lateglacial indicates that refugia for temperate trees were located along the Ebro valley during the Last Glacial Maximum. The Holocene sediments in the Salada Mediana records have been eroded, and the Upper Section represents deposition during the last few centuries., The Research in Salada Mediana was partially funded by the National Science Foundation (USA) under the EAR 941-8657 program, and by the Estación Experimental de Aula Dei and Instituto Pirenaico de Ecologı́a — CSIC (Spain). P. González-Sampériz received a grant from the Goverment of Aragón (CONSI+D).

WOS: 000332444900003, The Sivas basin (Turkey) shows pronounced salt tectonics activity involving the Oligocene evaporites. Despite the complete exposure of the structures, the tectonic evolution of the basin has been so far misunderstood because it has only been envisioned in a context of thrust tectonics. The core of the basin, a 35x25 km area, displays rounded minibasins separated by evaporitic walls, and partially covered by remobilized gypsum (either sedimentary or flowage). The minibasins are filled by Mid-Oligocene to Early Miocene clastics (fluvial silts and sandstones), marls, and lacustrine to marine limestones, the thickness of which may reach 4 kilometres. The stratal architecture along evaporite walls records the progressive subsidence of the minibasins, with strong rotation of beds, unconformities and local reworking of evaporites. Within the basin, the sediments show lateral thickness variations and spectacular angular unconformities. The observed geometries show striking similarities with the seismic data from petroleum basins suffering strong salt tectonism (gulf of Mexico, Precaspian basin, Angolan margin)., Total SA; Total SA "Structural geology Chair" at University of Pau and Pays de l'Adour; Cumhuriyet University, We thank Total SA for financial support. J.-P. Callot acknowledges a grant from Total SA "Structural geology Chair" at University of Pau and Pays de l'Adour. Cumhuriyet University is warmly thanked for their support and help during field work. J.-F. Salel and V. Martin (Cobalt Energy) helped in retrieving seismic data. M. Jackson, M. Hudec, B. Vendeville, an anonymous reviewer and editor O. Lacombe are warmly thanked for their pertinent reviews. The field party is acknowledge: C. Mallard, A. Pichat, E. Legeay, R. Graham, J. Letouzey, A. Rouchy, G. Hoareau, E. Surmeli, M.F. Surmeli, T. Kus, F. Birol, N. Keskin, S. Emrahoglu.

Hydraulic engineering is increasingly relied upon to provide the necessary dry-season discharge for Peru's hydroelectricity generation. Redirecting stream flow can yield unintended consequences, however, and here we document the wholesale contamination of the Lake Junín National Reserve by acid mine drainage from the Cerro de Pasco mining district. Since construction of the Upamayo Dam in 1932, the Río (river) San Juan, which drains the Cerro de Pasco region, has been seasonally redirected into Lake Junín. As a result, the upper several decimeters of sediment in the lake contain peak concentrations of Cu, Zn, and Pb of ̃6000 ppm, ̃50,000 ppm, and ̃2000 ppm, respectively, with the latter two greatly exceeding the United States Environmental Protection Agency (EPA) limits for the entire 150 km2 lake basin. That the source of the contamination to Lake Junín is acid mine drainage from Cerro de Pasco is supported by spatial gradients in metal concentrations, authigenic calcite (marl) concentrations, and the isotopic record of Junín water. Today, the upper 50 cm of sediment in Lake Junín contain ̃60,400, 897,600, and 40,900 metric tons of Cu, Zn, and Pb, respectively, which is equivalent to ̃5.1 years' worth of Zn extraction and ̃0.7 years' worth of Pb extraction from mining operations at Cerro de Pasco at current rates.

Here we report the recognition of the Minoan tephra layer in the Acigol Basin (western Turkey), which represents the most eastward occurrence of this tephra on land and the first in continental deposits out of lacustrine sediments in mainland Turkey. The correlation is supported by glass and mineral geochemistry, which includes solution and laser-ablation ICP-MS data for trace and rare earth elements. Thickness and grain size data allow the extension of already described occurrences to an area of about 359000 km2, from the eastern Mediterranean to Black Sea throughout centralwestern Turkey. Coupling dispersal area and grain-size data suggests the joint influence of high and low atmosphere dynamics in dispersal of fine ash during volcanic eruptions. The thickness and lateral continuity of the Minoan tephra in the Acigol Basin testifies to the widespread impact on the Late Bronze Age environment of mainland Turkey of this important ash deposit. Copyright (c) 2013 John Wiley & Sons, Ltd.

During the period 2008-2009, eight sampling stations were carried out on Lake Uluabat to assess trace element distribution in the lake sediments and to identify major sources of the sediment pollution. Ten elements, including Iron (Fe), Manganese (Mn), Zinc (Zn), Chromium (Cr), Nickel (Ni), Copper (Cu), Lead (Pb), Cadmium (Cd), Arsenic (As), Boron (B) were determined in the sampled lake sediments. The lowest and highest variation intervals (5.0377-27664.197 mg kg(-1)) were found for Cd and Fe, respectively. Concentrations of Cr (131.627 mg kg(-1)), Ni (220.032 mg kg(-1)) and Cd (5.0377 mg kg(-1)) in sediment samples were higher than in the other regions. Moreover, suspended solids, conductivity, pH, temperature and the organic matter % were found to affect the concentrations of sediment. On the basis of the findings of the study, it was concluded that higher concentrations of trace elements in dry seasons increased with the increase in suspended matter, pH, percentage organic content, and conductivity.

The provenance of the Permo-Triassic series of the Talayuelas anticline (Iberian Ranges) have been studied using UPb geochronology (laser ablation inductively coupled plasma mass spectrometry) of detrital zircons. These intracontinental siliciclastic series were formed by extensive sandy braided fluvial systems associated with ephemeral lake deposits and aeolian sediments, with paleocurrents suggesting constant NW-SE transport directions. Upper Permian reddish sandstones from the Upper Alcotas Formation (Lopingian) contain a dominant Variscan zircon population (290-360 Ma), which indicates source areas located in the axial zone of the Variscan belt, in the core of the Ibero-Armorican arc. However, in the Lower Triassic sandstones of the Can ̃izar Formation (Olenekian), the Variscan zircon population is almost completely replaced by Cadomian zircons (520-750 Ma), with important Avalonian (390-520 Ma), Mesoproterozoic (900-1750 Ma), Eburnian (1.78-2.35 Ga), and post-Eburnian and Archaean (>12.4 Ga) zircon populations. This detrital zircon content now suggests source areas located more to the NW, in the Avalonian microcontinent, although a limited supply coming from the southern part of Laurentia cannot be ruled out. Finally, in the Middle Triassic (Anisian), the source areas returned to the Variscan axial zone, since the Variscan zircon population is again highly dominant during this period. The changes detected in the source areas of the Permo-Triassic series are related to the development and propagation of the Iberian rift, one of the large extensional structures that determined the generation of the sedimentary basins and finally caused the breakup of Pangea. The methodology followed in this article is very useful to understand the generation and evolution of these intracontinental basins and also the relationships between the different rift systems generated in the North Atlantic realm during the Permo-Triassic times.

To examine the status and risk of heavy metal pollution, the distribution of As, Cd, Cr, Ni, and Pb in the sediment of Lake Uluabat was characterized. The present study used a four-stage method to assess the ecotoxicological effects of the heavy metal and trace elements fractions in the sediment of Lake Uluabat. Total Cr and Ni concentrations in the sediment were determined to have exceeded the severe effect level (SEL) limit values. The percentages of the variable fractions of Cr and Ni were below 10%. Because of this reason, they were not defined to have a high risk. The relationships among the physicochemical parameters, heavy metals and trace elements in water and sediment were determined statistically. Pb, Cd, and As in the water were found in relation with some of the fractions. Moreover, it was thought that the amounts of the elements of As releasing into the water might be increased due to their relations with the physicochemical parameters.

International audience; This paper presents geophysical and core data obtained from several marine geology surveys carried out in the western Black Sea. These data provide a solid record of water-level fluctuation during the Last Glacial Maximum in the Black Sea. A Last Glacial Maximum lowstand wedge evidenced at the shelf edge in Romania, Bulgaria, and Turkey represents the starting point of this record. Then, a first transgressive system is identified as the Danube prodelta built under ~40 m of water depth. The related rise in water level is interpreted to have been caused by an increase in water provided to the Black Sea by the melting of the ice after 18,000 yr B.P., drained by the largest European rivers (Danube, Dnieper, Dniester). Subsequently, the Black Sea lacustrine shelf deposits formed a significant basinward-prograding wedge system, interpreted as forced regression system tracts. On top of these prograding sequences, there is a set of sand dunes that delineates a wave-cut terrace-like feature around the isobath −100 m. The upper part of the last prograding sequence is incised by anastomosed channels that end in the Danube (Viteaz) canyon, which are also built on the lacustrine prograding wedge. Overlying this succession, there is a shelfwide unconformity visible in very high-resolution seismic-reflection profiles and present all over the shelf. A uniform drape of marine sediment above the unconformity is present all over the continental shelf with practically the same thickness over nearby elevations and depressions. This mud drape represents the last stage of the Black Sea water-level fluctuation and is set after the reconnection of this basin with the Mediterranean Sea.

This field experimental study simultaneously analysed the effects of predation (top-down) and nutrients (bottom-up) on planktonic communities (phytoplankton, zooplankton, heterotrophic nanoflagellates and ciliates) in a warm temperate wetland in South America. The top-down and bottom-up controls were investigated by assessing the impact of omnivorous-planktivorous fish (Jenynsia sp.) and the effects of nutrient input from natural lake sediments, respectively. Three treatments and a control were run in triplicate in mesocosms and samples were taken at Days 0, 3, 7 and 15. The control contained all the planktonic components while treatments included all planktonic components plus the addition of either planktivorous fish (F), natural wetland sediments in dialysis bags (S) or both of them (SF). A bottom-up effect due to nutrient release from sediment (mainly total phosphorus) was noticed in treatments S and SF. Phytoplankton abundance increased in all treatments compared with the control. Thus, phytoplankton appeared to be bottom-up controlled while fish exerted a strong predation pressure on zooplankton (top-down), because treatments F and SF showed a marked decrease in mesozooplankton abundance. The results obtained in this study agree with the hypothesis that phytoplankton regulation by zooplankton might be weaker in warm temperate systems than in temperate ones. Fil: Sinistro, Rodrigo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución. Laboratorio de Limnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

We present the first record of the cardiid genus Monodacna from the Pliocene of Anatolia, Turkey. Monodacna imrei sp. nov. was found in the Pliocene Killik Formation from the western margin of the Baklan Basin, in very marginal brackish to freshwater lacustrine deposits. The new record extends the stratigraphic range of the modern Ponto-Caspian genus back into the Pliocene and adds to earlier evidence that modern Ponto-Caspian taxa originated in the Pliocene of south-western Turkey. © The Palaeontological Association.

[1] The Colima Volcanic Complex (CVC) is currently the most active Mexican volcano and is located in the western sector of the Trans–Mexican Volcanic Belt, inside the active Colima Rift, a regional N-S-striking extensional structure. The Colima Rift is filled by a ∼1 km-thick sequence of quaternary lacustrine sediments, alluvium, and colluvium, mostly underling the about 3000-m-thick volcanic pile of the CVC. In this work we present the results of a detailed morphostructural and field study of Quaternary faults and fractures in the CVC and the surrounding area, including the regional structures of the Colima Rift. We also present a geometrical modeling of the faults inside the volcano and a numerical model of the gravity-induced stress and strain fields of the CVC. The study attempts to characterize the geometry, kinematics, and dynamics of the deformation features of the CVC and relate it with the volcano structure, the geology of the substratum, and the geodynamic setting of the region. Our model considers that the observed deformation of the CVC and the surroundings results from the interplay between the active N-S-trending regional extensional tectonics and the southward spreading of the volcano over its basement forming an E-W-oriented volcanotectonic graben. The interaction between regional tectonics and previously unrecognized volcanic spreading can control magma migration and flank instability, in an area where eruptions and sector failures represent a potential high risk for more than 500,000 people.