bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of different forms of organic carbon on the partitioning and bioavailability of nonylphenol
Authors: Burgess Robert M. , Pelletier Marguerite C. , Gundersen Jennifer L. , Perron Monique M. , Ryba Stephan A. 
Published: June 2005

Abstract
Oxygenated nonpolar organic contaminants (NOCs) are underrepresented in studies of the partitioning and bioavailability of NOCs, including nonylphenol. In this investigation, we evaluated the toxicity, partitioning, and bioavailability of nonylphenol as affected by different forms of organic carbon. Along with organic carbon content, the role of organic carbon polarity was assessed. Toxicity of nonylphenol to a mysid and amphipod was comparable to results reported in the literature for marine organisms with median lethal concentrations (LC50s) of 82.3 and 236 μg/L, respectively. The presence of the different forms of organic carbon in every instance altered, often statistically significantly, the toxicity and bioavailability of the nonylphenol and increased the LC50 by approximately a factor of two. Partition coefficients (KPs) for nonylphenol ranged from 21.3 for cellulose to 9,770 for humic acid; log organic carbon-normalized partition coefficients (KOCs) ranged from 1.71 for cellulose to 4.71 for sediment. An exercise to predict nonylphenol effects using our toxicity data and normalized partition coefficients indicated organic carbon content was most protective and also highlighted the need for further research to better understand nonylphenol bioavailability. These data suggested that with regard to partitioning and bioavailability, the oxygenated NOC nonylphenol behaves like conventional NOCs. The data also suggest that, with refinements, polarity may have some advantages in predicting nonylphenol bioavailability.
Acute and chronic toxicity of lead in water and diet to the amphipod Hyalella azteca
Authors: Besser John M. , Brumbaugh William G. , Brunson Eric L. , Ingersoll Christopher G. 
Published: June 2005

Abstract
We evaluated the influence of waterborne and dietary lead (Pb) exposure on the acute and chronic toxicity of Pb to the amphipod Hyalella azteca. Test solutions were generated by a modified diluter with an extended (24-h) equilibration period. Acute (96-h) toxicity of Pb varied with water hardness in the range of 71 to 275 mg/L as CaCO3, despite similar dissolved Pb concentrations. Acute toxicity was greatest in soft test water, with less than 50% survival at the lowest dissolved Pb concentration (151 μg/L). Survival also was significantly reduced in medium-hardness water but not in hard test water. In chronic (42-d) studies, amphipods were exposed to waterborne Pb and fed either a control diet or a diet equilibrated with waterborne Pb levels. For animals fed the control diet, the median lethal concentration (LC50) for Pb was 24 μg/L (as dissolved Pb), and significant reductions in survival occurred at 16 μg/L. Exposure to Pb-treated diets significantly increased toxicity across a wide range of dissolved Pb concentrations, with a LC50 of 16 μg/L and significant reductions in growth and reproduction at 3.5 μg/L. Significant effects on growth and reproduction occurred at dissolved Pb concentrations close to the current U.S. chronic water-quality criterion. Our results suggest that both aqueous- and dietary-exposure pathways contribute significantly to chronic Pb exposure and toxic effects in aquatic biota.
Effects of ionic liquids on the survival, movement, and feeding behavior of the freshwater snail, Physa acuta
Authors: Bernot Randall J. , Kennedy Erin E. , Lamberti Gary A. 
Published: June 2005

Abstract
Room-temperature ionic liquids (ILs) are being promoted as environmentally friendly alternatives to volatile organic solvents currently used by industry. Because ILs are novel and not yet in widespread use, their potential impact on aquatic organisms is unclear. We studied the effects of several ILs on the survivorship and behavior (movement and feeding rates) of the freshwater pulmonate snail, Physa acuta. Median lethal concentrations (LC50s) of ILs with imidazolium- and pyridinium-based cations and Br− and PF−6 as anions ranged from 1 to 325 mg/L. Toxicity was greatest for ILs with eight-carbon alkyl chains attached to both imidazolium and pyridinium rings and declined with shorter alkyl chains, indicating a positive relationship between alkyl chain length and toxicity. Compared to controls, snails moved more slowly when exposed to butyl- and hexyl-cation ILs at 1 to 3% of LC50 concentrations but were not affected at higher IL concentrations (4–10% of LC50), which is characteristic of U-shaped dose-response curves. Snail movement was not affected by ILs with octyl alkyl groups. Grazing patterns, however, indicated that snails grazed less at higher IL concentrations. Physa acuta egestion rates were reduced in the presence of ILs at 3 to 10% of LC50 concentrations. Thus, nonlethal IL concentrations affected P. acuta behaviors, potentially impacting individual fitness and food web interactions. These results provide initial information needed to assess the potential hazards of ILs should they reach freshwater ecosystems.
Datation par les foraminiferes planctoniques d'une activite volcanique d'age lutetien a Toubab Dialow (Senegal occidental)
Authors: Sarr Raphael , Ndiaue Papa Moussa , Niang-Diop Isabelle , Gueye Mamadou 
Published: June 2005

Abstract
A level of silicified limestones with nummulites and daucines has been discovered in Toubab Dialaw, located in the horst of Ndiass. Interbedded between the diatreme and the ferruginous lateritic crust, this level is characterized by sheath folds. The biostratigraphic analysis revealed the presence of nummulites, daucina and a planktonic association with Globigerinatheka kugleri (Bolli, Loeblich et Tappan, 1957) which characterizes P11-P13 zones of late Lutetian to early Bartonian age. This indicates that the Tertiary volcanic activity in the Cap Vert peninsula, here represented by the Toubab Dialaw diatreme, till now considered late Eocene to late Pliocene, began earlier, during the Middle Eocene and more precisely between 48 and 45 Ma. Moreover, the presence of sheath folds indicates that the sedimentary material has been subject to a submarine slide along a low slope. Finally, all the petrographical, palaeontological and structural data allow to precise the set up history of the volcanic and sedimentary formations constituting the littoral cliffs of Toubab Dialaw.
The Paleocene/Eocene-boundary interval of a Tethyan deep-sea section (Austria) and its correlation with the North Sea basin
Authors: Egger Hans , Heilmann-Clausen Claus , Schmitz Birger 
Published: June 2005

Abstract
The Anthering-section is one of the most expanded upper Paleocene - lower Eocene sedimentary sequences known to date and records several of the Paleocene/Eocene boundary events, including the delta 13 C isotope excursion. Within 250 m of abyssal-plain deposits, calcareous mud-turbidites originating from the basin slope alternate with hemipelagic claystones. The average rate of sedimentation for the lower part of Zone NP9 is calculated at 22.7 cm/ky and for the upper part of Zone NP9 and Zone NP10 at 9.1 cm/ky. In the lower part of Zone NP10 closely spaced bentonite layers occur which mainly display immobile element concentrations typical for alkaline basalts. However, the thickest bentonite (X1), situated at the base of the ash series, plots into the trachyte field. Dinoflagellate stratigraphy strongly suggests that the ash-series at Anthering is synchronous with the main occurrence of ash layers in the North Sea region which display a comparable chemical composition. The biostratigraphical and geochemical correspondence of both ash-series point to a common source of magma. Especially, a correlation of layer +19 of the North Sea region with layer X1 at Anthering seems probable. We therefore consider the bentonites from the Anthering-section as distal deposits of the "positive" ash-series of the North Sea region which obviously represent unique and widespread correlation tools.
Orbital control on pelagic clay sedimentology; the case of the late Albian "Amadeus Segment" (central Italy)
Authors: Tateo Fabio , Morandi Noris , Nicolai Annarita , Ripepe Maurizio , Coccioni Rodolfo , Galeotti Simone , Baudin Francois 
Published: June 2005

Abstract
The Amadeus Segment which falls within the Oceanic Anoxic Event 1c, is a composite stratigraphic interval of late Albian age, composed by frequent alternation of black shales characterised by organic carbon content usually lower than 1% and carbonate-richer sediments. Geochemical and clay mineral signatures indicate a coarser grain size for the black shales, and geochemical data from literature indicate a continental origin of the organic matter. Most of the geochemical variables analyzed show a record which follows an orbital cyclicity, with the exception of Mn and Ba, whose mobility after burial was identified by independent compositional criteria. The spectral analysis succeeded in identifying such compositional peculiarities, and also enabled to correlate the Amadeus Segment with the Segment-1 of the nearby Piobbico Core. The Milankovitch cyclicity (low eccentricity and obliquity) deeply affects the sedimentation of the Amadeus Segment, because orbital frequencies characterize the distribution of foraminiferal and compositional variables, which are both controlled by organic productivity and by detrital supply (dilution effect excluded). The high frequency changes from carbonate-rich layers to black shales are interpreted as changes in oceanographic regimes which in turn caused variations in the dispersal regime of continental inputs and in productivity.
New data on the flora and fauna from the ?uppermost Carboniferous-Lower Permian of Buxieres-les-Mines, Bourbon l'Archambault Basin (Allier, France); a preliminary report
Authors: Steyer J. Sebastien , Escuillie Francois , Pouillon Jean-Marc , Broutin Jean , Debriette Pierre , Freytet Pierre , Gand Georges , Poplin Cecile , Rage Jean-Claude , Rival Jacques , Schneider Joerg W. , Stamberg Stanislav , Werneburg Ralf , Cuny Gilles 
Published: June 2005

Abstract
New fossils from the ?uppermost Carboniferous-Lower Permian have been found at Buxieres-les-Mines (Massif central, France). In this preliminary article we report on algae, stromatolites, palynomorphs, macroflora, ostracods, insects, elasmobranchs, acanthodians, actinopterygians and amphibians. Elasmobranchs and amphibians are diversified compared with those of other European localities. Most taxa indicate lacustrine deposits and an Asselian age, and permit us to address the question of the palaeoecosystem evolution of the Bourbon-l'Archambault Basin, during the Lower Permian.
Des boules de bousiers fossiles et leurs terriers dans les sites a Australopitheques du Pliocene tchadien
Authors: Duringer Philippe , Brunet Michel , Cambefort Yves , Beauvilain Alain , Mackaye Hassane Taisso , Vignaud Patrick , Schuster Mathieu 
Published: June 2005

Abstract
The structures under study belong to the Pliocene continental formation of the palaeo-lake Chad system. This formation is famous for the discovery, in 1995, of the first australopithecine from Chad associated with a rich fauna of mammals, birds, reptiles and fishes. The analysis of this fauna and the interpretation of the depositional environment reveal a landscape of gallery forest, savannah grasslands, and ephemeral rivers interrupted by lacustrine episodes. The sandstone facies contains sandstone balls of 4 to 12 centimetres in diameter, lightly flattened at the poles. These structures are characterized by an external husk or crust and by a centimetric cavity in the upper part of the ball. Between the husk and the cavity, there exists a number of concave laminae, similar to those of a bulb, whose concavity is directed toward the upper cavity. These balls are associated with a vast metre-scale gallery network. This sandstone balls are interpreted as fossil brood-balls of dung beetles (Coleoptera, Scarabaeidae). Comparisons between these structures and the brood-balls of modern Scarabaeidae reveal great similarity, especially in the external husk, the concave internal laminae, and the chamber for the larva in the upper part of the structures.
Les oeufs de dinosaures du Cretace superieur du bassin de Villeveyrac-Meze (Herault, France); description d'une nouvelle ooespece de Prismatoolithus
Authors: Garcia Geraldine , Feist Monique , Cabot Alain , Valentin Xavier , Vianey-Liaud Monique 
Published: June 2005

Abstract
The dinosaurian eggshell localities, found recently in the Villeveyrac-Meze basin allow to precise the datation of the continental levels overlaying the Villeveyrac Campanian series. They also provide information on the oospecies diversity in the Campano-Maastrichtian of southern France. Seven Megaloolithidae species which are already known in the Aix basin have been identified as well as a new prismatoolithid species, Prismatoolithus caboti.
Modification of the original stratigraphic distribution of Globigerina hillebrandti Orue-Etxebarria, 1985 and its inclusion in another genus; one more planktonic foraminifer species surviving the mass extinction of the K/T boundary
Authors: Orue-Etxebarria Xabier , Apellaniz Estibaliz 
Published: June 2005

Abstract
The detailed study of K/T sections in western Pyrenees, SE of the Iberian Peninsula and Tunisia demonstrate that Hedbergella hillebrandti previously thought to be restricted to the Lower Paleocene also occurs from the Upper Maastrichtian. This species originally attributed to the genus Globigerina is transferred in Hedbergella and is one of the planktonic foraminifers surviving the mass extinction of the K/T boundary.
Mode d'empilement et distorsion de sequences genetiques en milieu marin restreint; facies et architecture des depots hettangiens du sud-ouest du bassin de Paris
Authors: Merzeraud Gilles , Rauscher Raymond , Hoffert Michel , Verdier Francois 
Published: June 2005

Abstract
In the southwestern part of the Paris Basin (Sologne region), dolomite and limestone deposits of Hettangian age represent an excellent cover for a thick sandstone reservoir, which is being worked by "Gaz de France" for natural gas storage in underground aquifers. The "genetic sequences" of these shallow marine deposits and their stacking patterns are associated with two orders of relative sea-level fluctuations. The thinnest genetic sequences are arranged in transgressive/regressive hemicycles that include distinct facies assemblages. The facies changes are related to rapid palaeogeographic variations that occur during the onset of each genetic sequence. On a different scale, the stacked genetic sequences are organized into three geometric patterns, which are related to long-term eustatic fluctuations (eg. aggradational, retrogradational, and progradational patterns). For each of these stacked geometries, the partitioning of sediment volumes, the degree of symmetry, and the two-dimensional architecture of the genetic sequences had been modified through time. These changes are related to the effects of two superimposed short-term and long-term sea-level oscillations that distort the stratigraphic record.
Les glissements rocheux du versant sud du Layens (Vallee d'Aspe, Pyrenees occidentales)
Authors: Fabre Richard , Desreumaux Christian , Lebourg Thomas 
Published: June 2005

Abstract
Detailed geological surveys carried out recently on the Layens have permitted to redefine the lithostratigraphy and to establish the structure of its south slope where several rockslides have been precisely located. This south slope is composed of a carbonaceous Mesozoic series ranging from the Triassic up to the Lower Cretaceous which is located on the reverse flank of a large overfolded north north-eastern syncline. The lithological and structural heritage, together with its special geodynamic setting, generate many brittle zones which favour the mechanical instability of the slope. On this basis the morphostructural position of the rockslides has been established, some of which are unstable while others are stable. Two stages in the evolution of the rockslides have been deduced from the geomorphology and mapping. These field observations have enabled us to distinguish three different rockslides (A, B, C) which are either deep or superficial. The analysis of the causes of their instability have been considered by taking into account the orientation of the major mechanical discontinuities, inherited from the structural context, as well as the sensitivity to the slipping of Triassic clay formations. The natural causes of the destabilization of the south slope of the Layens have been established for the most active rockslide : the geological surveys permit an evaluation of the volume and the total displacements.
Utilisation du 10 Be cosmogenique produit in-situ pour l'etude de la dynamique et de l'evolution des sols en milieux lateritiques
Authors: Braucher Regis , Siame Lionel , Bourles Didier , Colin Fabrice 
Published: June 2005

Abstract
In situ-produced cosmonuclides result from nuclear reactions between cosmic-rays derived particles and the elements constituting the Earth's surface material. Cosmogenic 10 Be (T1/2 = 1,5Ma) and 26 Al (T1/2 = 0.73 Ma) produced within the quartz mineral fraction of surficial rocks have been used to quantitatively study the emplacement and development of laterites. Depth distributions of in situ-produced 10 Be along quartz veins and soil profiles permit: (1) to clarify mechanisms involved in soil formation and landform evolutions, (2) to quantify burial or denudation rates. Lateral variations of the in situ-produced 10 Be concentration along stone-lines allow to determine whether the stone-line constituting material has an allochthonous or an autochthonous origin, and, in the latter case, to estimate the lateral displacement rates.
Les lahars; depots, origines et dynamique
Authors: Lavigne Frank , Thouret Jean-Claude 
Published: June 2005

Abstract
A lahar is a flowing mixture of rock debris and water (other than normal streamflow) from a volcano, which encompasses a continuum from debris flows (sediment concentration &gt; or =60% per volume) to hyperconcentrated streamflows (sediment concentration from 20 to 60% per volume). Debris flow deposits are poorly sorted and massive with abundant clasts. Lahars can be either syn-eruptive, post-eruptive or have a non-eruptive origin. Four types of lahars can be generated during an eruption, based on distinct sources of water (i.e. ice, snow, crater lake, river, and rain) that allow the sediments to be removed and incorporated in the lahar (e.g., Mount St.-Helens in 1980, Nevado del Ruiz in 1985). Post-eruptive lahars, which are rain-triggered, occur during several years after an eruption (e.g., still occurring at Pinatubo). Non-eruptive lahars are flows generated on volcanoes without eruptive activity, particularly in the case of a debris avalanche or a lake outburst (e.g., Kelud or Ruapehu). Lahars flow as pulses, whose velocity and discharge are much higher than those of streamflows, including catchments similar in size. Sediment transport capacity of lahars is exceptional, owing to buoyancy, dispersive pressure, and to the amount of cohesive clay and silt. However, the finding of recent experimental works indicates that even clay-rich lahar mixtures have little true cohesion. Therefore, the typical classification of lahars into "cohesive" and "non cohesive" seems to be inappropriate at present. Besides, past work on lahar mechanics used models based on the Bagnold's or the Bingham's theories. Recent advances in experimentation show that a lahar has specific rheological properties: it moves as a surge or series of surges, driven by gravity, by porosity fluctuation, and by pore fluid pressures, in accordance with the Coulomb grain flow model. Grain size distribution and sorting control pore pressure distribution. Lahar mechanics depend on much more than steady-state rheology, because lahars are highly unsteady and typically heterogeneous flows. Lahar can show a succession of debris flow phases, hyperconcentrated flow phases, and sometimes transient streamflow phases. Therefore, some fluids-mechanics concepts and terminology, such as "viscous", "laminar" or "non-Newtonian" are inappropriate to describe the mechanical properties of lahars. Processes of deposition are complex and poorly known. Interpretation of massive and unsorted lahar deposits commonly ascribe the deposition regime to a freezing en masse process. However, recent laboratory experiments highlight that debris-flow deposits may result from incremental deposition processes.
Caracteres structuraux et dynamiques d'un bassin en transtension; la plate-forme tunisienne a l'Ypresien terminal
Authors: Gourmelen Claude , Rigane Adel , Broquet Paul , Truillet Rene , Aite Mohamed Ouramdane 
Published: June 2005

Abstract
In Tunisia, Ypresian carbonate deposits occur on a platform preserving vestige of an inherited fault network. The fault network delineates blocks of different sizes accounting for the platform morphology and in turn for variation in thickness of the Ypresian sequence. The nummulitic limestone carapace of the Ypresian sequence is fractured by faults and joints of various orientations which are systematically sealed by marly beds of early Lutetian age. This indicates that the fault network was reactivated during late Ypresian. Geometric and kinematic study indicates that this strike slip late reactivation is accomodated by normal fault. These structures originated in soft sediment undergoing diagenesis. Depending on bed competency, both ductile and brittle deformation features were recognized in the fault. This superficial tectonic event represents, a recent reactivation of ancient fractures cartographically located on the boundaries of late Ypresian megablocks. Kinematic study of the deformation within and along the boundaries of one of these blocks, (Ousseltia block), indicates a late Ypresian, early Lutetian strike-slip distensive faulting dynamic. Stress-field orientation indicates a rapid re-orientation in time from a predominantly NW-SE extensional tectonic to a NE-SW extensional event. Stratigraphic dating of that tectonical crisis coincides with a turbulent period of relative motions between Europe and Africa.
La desilicification des silex des formations residuelles a silex de l'ouest du bassin de Paris
Authors: Laignel Benoit , Meyer Robert 
Published: June 2005

Abstract
In NW Europe, chalk areas are generally covered with clay-with-flints (CWF). These formations are made of flints with a clayey or silty-clayey matrix. In the literature devoted to CWF, the flint dissolution during the weathering of chalk was poorly studied. In this study, we provide an estimation of this phenomenon in the western Paris Basin, by comparisons between the flints of CWF and those of chalks based on mineralogy, size, cortex and surface cavities of flints. Our results show that the mineralogy and thickness of flints have not been affected by the weathering. Only the volumes of cortex and surface cavities have increased. These two parametres allow us to quantify the flint dissolution. Flint dissolution is low: the amount of dissolved silica in flints varies between 0.9 and 7.3%. These low values show that weathering of chalk who has led to the creation of CWF has not reached the intensity of a lateritic type weathering, as is the case in the ferralitic soil.
Morphodynamique fluviale et neotectonique dans la vallee de l'Oise (Bassin parisien, France)
Authors: Larue Jean-Pierre 
Published: June 2005

Abstract
To show the impact of neotectonics on fluvial morphodynamics, the author presents a geomorphological study of the Oise valley where it crosses the Pays de Bray anticline, and of the gullies and the dry valleys of the Pays de Thelle. The analysis of alluvial and colluvial forms and formations makes it possible to reconstruct the longitudinal profiles of successive river beds, from the valley heads to the Oise valley and thus to reveal anomalies. Tectonics control fluvial dynamics, but impacts are only observed if the climatic conditions are favourable: hence it can be deduced that the gullies were formed during the wet Subboreal period.