Search results for "Sediment"
showing 10 items of 1648 documents
Magnetostratigraphy and biostratigraphy of the Carnian/Norian boundary interval from the Pizzo Mondello section (Sicani Mountains, Sicily)
2001
The 146.5 m-thick Upper Triassic limestone section at Pizzo Mondello in the Sicani Mountains of western Sicily is characterized by high quality of exposure, accessibility, and stratigraphic continuity. Magnetostratigraphic results delineate 12 normal and reverse polarity magnetozones, labelled successively from the base upwards as PM1n, PM1r, PM6n, PM6r. The Carnian/Norian boundary, based on conodont biostratigraphy, falls somewhere in the PM3n to PM5n interval which corresponds to the E14n to E16n magnetozone interval in the Newark reference sequence of polarity reversals. Comparison of magnetobiostratigraphic data from the Newark basin, Pizzo Mondello and other Late Triassic marine sectio…
Unraveling the origin of the Late Triassic multitaxic bone accumulation at Krasiejów (S Poland) by diagenetic analysis
2012
Abstract A study of aquatic and terrestrial vertebrate remains from a bonebed in the Late Triassic continental succession near Krasiejow (S Poland) shows it was deposited by a single catastrophic event, perhaps a flood. Hardparts of Metoposaurus, Paleorhinus, and Stagonolepis show sedimentary infill and geochemical evidence for early diagenesis at different times and in different microenvironments. The infills in the aquatic animal bones (sediment, pyrite and calcite) show deposition in a freshwater environment, while those in the terrestrial Stagonolepis remains (mainly barite) point to an arid terrestial environment. The trace element content of the remains, together with the absence of a…
Trophic Transfer of Trace Elements in an Isotopically Constructed Food Chain From a Semi-enclosed Marine Coastal Area (Stagnone di Marsala, Sicily, M…
2012
Trace element accumulation is particularly important in coastal and transitional environments, which act as contaminant buffers between the continental and marine systems. We compared trace element transfer to the biota in two locations with different open-sea exposures in a semi-enclosed marine coastal area (Stagnone di Marsala, Sicily, Italy) using isotopically reconstructed food chains. Samples of sediment, macroalgae, seagrasses, invertebrates, fish, and bird feathers were sampled in July 2006 and analysed for stable carbon and nitrogen isotopes (δ(13)C, δ(15)N) and trace elements (arsenic [As], cadmium [Cd], total mercury [THg], and lead [Pb]). Trophic magnification factors were calcul…
Vertical stratification of bacteria and archaea in sediments of a small boreal humic lake
2019
Efecto de la carga orgánica y de nutrientes y su biorremediación en sedimentos de ecosistemas acuáticos con distintas características ecológicas
2014
En la presente tesis se seleccionaron como sistemas modelo de estudio dos ecosistemas acuáticos con características ecológicas muy distintas aunque con una problemática ambiental en común: la acumulación de materia orgánica en sus sedimentos (en distinto grado) como consecuencia de la actividad humana. En ambos casos se abordó el estudio tanto del efecto de la adición externa de nutrientes como de la desorción de estos desde sus sedimentos. Posteriormente se evaluó la eficacia de diferentes técnicas de biorremediación para reducir la carga orgánica y de nutrientes en estos sedimentos. El primero de los sistemas acuáticos seleccionados, la Laguna de Talayuelas, se trata de una laguna endorre…
The fate aspects of pharmaceuticals in the environment : biotransformation, sedimentation and exposure of fish
2012
Zawartość niektórych metali ciężkich w osadach dennych wybranych zbiorników retencyjnych
2005
Geochemistry and petrography of box-core sediments from a methane seep setting in the Strait of Sicily, central Mediterranean
2008
Middle Miocene–Early Pliocene wedge-top basins of NW Sicily (Italy): constraints for the tectonic evolution of a ‘non-conventional’ thrust belt, affe…
2014
The study of geological evolution of a multiphase orogenic belt is complex, expecially when the tectonic events are superimposed in a coaxial fashion. The Sicilian fold-and-thrust belt represents an interest- ing case study, as a non-coaxial superimposition of structures is recognizable, owing to large synkinematic clockwise rotations during each of two subsequent compressional events. These rotations involved also the syntectonic basins that developed in the wedge-top depozone. This study aims to constrain the tectono-depo- sitional evolution of the NW Sicily fold-and-thrust belt and the associated wedge-top depozone between the middle Miocene and the early Pliocene. Integrated analyses of…
Sedimentological and diagenetic influences on low permeability properties of the Middle Jurassic limestones (Paris Basin, France)
2009
A detailed sedimentological, geochemical and mineralogical study is carried out on the Early Bajocian to Early Callovian (Middle Jurassic) limestones of the Paris Basin. Deposits include 18 lithofacies which are stacked into 10 third-order depositional sequences. Our geochemical study including a compilation of bibliographic data allows us to refine the existing sea surface palaeotemperature pattern. A cooling from the latest Early Bajocian to the Late Bajocian and a subsequent warming from the earliest Callovian to the Early/Middle Callovian transition are described using a proxy of sea surface temperatures. Together with δ13C and mineralogical data, our new δ18O values suggest a palaeo-cl…