Search results for " Sediment"

Effects of glaciation on karst hydrology and sedimentology during the Last Glacial Cycle: The case of Granito cave, Central Pyrenees (Spain)

2021

In Alpine regions, speleothem development on karst systems largely occurs during warm interglacial or interstadial phases due to their limited growth during cold stages. Still, recent attention has been given to the role of clastic sediments in caves, less dependent on temperature conditions. Yet, only a small number of caves worldwide preserve both speleothems and detrital deposits. Here we present an outstanding record of fine-grain laminated sediments and carbonate speleothems from the Granito cave (South Central Pyrenees, Spain) associated with seasonal to annual hydroclimatic pulses through the Last Glacial Cycle (LGC). Analysis of cave clastic facies together with new absolute dates o…

Heterogeneity of volatile sources along the Halmahera arc, Indonesia

2021

co-auteur étranger; International audience; The parallel Halmahera and Sangihe arcs in eastern Indonesia are sites of active arc-arc collision of considerable interest in developing understanding of the geodynamics and geochemistry of subduction zones. Owing to the comparative remoteness of the region, few ground-based studies of the volcanoes have been undertaken. Here, we report and integrate gas measurements and (isotope) geochemical analyses of lava samples for Dukono, Ibu, Gamkonora, Gamalama, and Makian volcanoes of the Halmahera arc. Summing gas fluxes for all five volcanoes indicates arcscale emission budgets for H 2 O, CO 2 , SO 2 , H 2 S, and H 2 of 96300±27000, 2093±450, 944±400,…

Birth and Early evolution of a Jurassic Escarpment: Monte Kumeta, Western Sicily

2002

The accurate reconstruction of the facies architecture in the Jurassic succession of Monte Kumeta, coupled with a detailed biostratigraphy, allow to define dynamics and genetic factors controlling the conversion of a Bahamian-type carbonate platform to a pelagic escarpment. A change from tidalites to oolites i.e. from the restricted, interior lagoon to a more open-marine sandy depositional environment, records the establishment of a basin south of the Monte Kumeta sector in late Hettangian-Sinemurian times. The oolitic limestones are overlain by earliest Carixian bioclastic grainstones and packstones with micritized grains and by wackestones with radiolarians and sponge spicules, organized …

STOP 10: Kame terrace in the Upper Daugava depression at Rakuti, near Krāslava

2014

Clastic injection dynamics during ice front oscillations: A case example from Sólheimajökull (Iceland).

2015

18 pages; International audience; Soft-sediment deformation structures are being increasingly used as a tool for reconstructing palaeoenvironments and porewater pressure conditions in glacial settings. However, the potential of hydrofractures and clastic injections in the reconstruction of ice dynamics remains poorly constrained. This paper presents the results of a detailed study of a clastic injection network outcropping in the Sólheimajökull forefield (South Iceland). Sedimentological descriptions are combined with microscopic to macroscopic analyses of clastic injection geometries, sediment-fills, and cross-cutting relationships. The 250 m long and 20 m high exposure observed along the …

Geophysical investigation of Pleistocene volcanism and tectonics offshore Capo Vaticano (Calabria, southeastern Tyrrhenian Sea)

2015

Abstract Magma upwelling forming volcanic plumbing systems in back arc settings is typically controlled by extensional tectonic structures of the upper crust. Here we investigate this process in the area between the volcanic arc of the Aeolian Islands and the Calabrian arc (SE Tyrrhenian Sea) by integrating morpho-bathymetry and reflection seismic data with the outcomes of “Inverse 3D magnetic modeling” of previously gathered aeromagnetic data. Morpho-bathymetric data highlight the presence of a seamount ∼10 km offshore Capo Vaticano Promontory (eastern Calabria). This feature, named Capo Vaticano seamount is composed of a series of NE-trending ridges, the greatest of which (R1) is ∼12 km l…

Potential and limits of combining studies of coarse- and fine-grained sediments for the coastal event history of a Caribbean carbonate environment

2013

The coastal deposits of Bonaire, Leeward Antilles, are among the most studied archives for extreme-wave events (EWEs) in the Caribbean. Here we present more than 400 electron spin resonance (ESR) and radiocarbon data on coarse-clast deposits from Bonaire’s eastern and western coasts. The chronological data are compared to the occurrence and age of fine-grained extremewave deposits detected in lagoons and floodplains. Both approaches are aimed at the identification of EWEs, the differentiation between extraordinary storms and tsunamis, improving reconstructions of the coastal evolution, and establishing a geochronological framework for the events. Although the combination of different method…

Water resource assessment in karst and fractured aquifers of Termini Imerese-Trabia Mts. (Northern central Sicily, Italy).

2014

The carbonatic siliciclastic Mesozoic reliefs of Termini Imerese-Trabia Mts. (Northern central Sicily) were selected in order to investigate groundwater resources, as these fissured to karstic aquifers are used for potable water supply. These reliefs, part of the Sicilian Apennine Chain, consist of a tectonic units (deformed and emplaced during the Miocene-Pleistocene, and collapsed during the Plio-Pleistocene) mostly formed by clayey pelagic limestones (Sicilidi domain) overthrusting Meso-Cenozoic carbonate and silicoclastic rocks (Imerese Basin, Late Triassic-Early Oligocene) and terrigenous covers (Numidian Flysch, Late Oligocene-Early Miocene). The evolution of karstic network and subsu…

Geological Map of the Rocca Busambra-Corleone region (western Sicily, Italy): explanatory notes

2011

The geology of the Rocca Busambra-Corleone region, in centralwestern Sicily, is relevant to the understanding of the central sector of the Maghrebian-Sicilian fold-and-thrust belt. In the investigated area Mesozoic shallow- and deep-water carbo - nate deposits pertaining respectively to the Trapanese and the Sica - nian successions, and a thick Oligo-Miocene numidian flysch body, crop out. Minor outcrops of Cretaceous-Palaeogene Sicilide complex and syn-orogenic deposits of the Late Serravallian-Early Messinian Castellana Sicula and Terravecchia formations are also present. A structural analysis reveals complex tectonic relationships between the Trapanese carbonate platform tectonic unit (t…

Deep controls on foreland basin system evolution along the Sicilian fold and thrust belt

2015

Abstract Neogene-Quaternary wedge-top-basins arose during the Sicilian fold and thrust belt (FTB) build-up. The infilling sedimentary successions are: i) middle-upper Miocene silicoclastics succession, accommodated on top of the accreted Sicilide and Numidian flysch nappes; ii) upper Miocene-lower Pliocene deepening-upwards sediments unconformably overlying the inner Meso-Cenozoic deep-water, Imerese and Sicanian thrust units; iii) Upper Pliocene-Quaternary coastal-open shelf deposits unconformably covering (in the outer sector of the FTB) a tectonic stack (Gela thrust system). These successions are characterized by a basal unconformity on the deformed substrate believed to be the depositio…