Search results for "carbonate platform"

Multi-scale dissolution events in Western-Tethyan peritidal carbonates close to the Triassic/Jurassic boundary

2015

The stratigraphical and sedimentological study of uppermost Triassic-lowermost Jurassic sections of peritidal carbonates, in north-western Sicily, allows to differentiate multi-scale dissolution events that affected the carbonate platform interior during the uppermost Rhaetian. The Triassic cycles show extensive phenomena of stratabound dissolution that can be differentiated in three main types: vug, moldic and “spongy-like”. The dissolution horizons are particularly concentrated in the subtidal members of cycles. The creation of different type of porosity seems to be mainly controlled by the textural characters of the host-rock. In particular the cm-scale bioturbation in muddy sediments, p…

Processi paleocarsici e geositi: il caso del “libeccio antico” nel distretto marmifero di Custonaci, Sicilia nord-occidentale

2016

Abstract The Upper Triassic strata that crops out along the northern slope of Monte Sparagio, in the Custonaci “marble” district in northwestern Sicily, show an extensive development of dissolution cavities with a very variable shape and dimensions. Several different types of dissolution morphologies can be differentiated from microkarst to giant caverns. The cavities are filled up by polychrome silts or calcite cements or, in the larger caverns, by collapse breccias. The matrix between the collapse breccias is a polychrome silt that gives rise to an attractive ornamental stone, quarried in the past with the name of “Libeccio Antico”. The diagenetic processes that have controlled the format…

Carbonate platform-basin systems in Sicily around the Triassic/Jurassic boundary: new data from the Campofiorito area (Sicani Mountains, western Sici…

2006

Sequence stratigraphy of a mesozoic carbonate platform-to-basin system in Western sicily

2009

Abstract Sequence stratigraphic studies of the Triassic through Paleogene carbonate successions of platform, slope and basin in western Sicily (Palermo and Termini Imerese Mountains) have identified a sedimentary cyclicity mostly caused by relative oscillations of sea level. The stratigraphic successions of the Imerese and Panormide palaeogeographic domains of the southern Tethyan continental margin were studied with physical-stratigraphy and facies analysis to reconstruct the sedimentary evolution of this platform-to-basin system. The Imerese Basin is characterized by a carbonate and siliceous-calcareous succession, 1200–1400m thick, Late Triassic to Eocene in age. The strata display a typ…

Triasina hantkeni limestones from western Sicily

2010

End Triassic karstification of a south Tethyan carbonate platform: the genesis of the “Libeccio Antico” a famous Baroque dimension stone.

2010

Acidification processes in a peritidal carbonate succession across the Triassic/Jurassic boundary (Sicily)

2017

For the first time, a correlation between biostratigraphic events and δ13C curve was attempted along an UpperTriassic-Lower Jurassic peritidal limestone succession cropping out in westernmost Sicily. The peritidal carbonates are organized in shallowing upward cycles characterized by subtidal skeletal mudstone to grainstone, intertidal microbial mats and supratidal paleosoils. About 300 meters of this succession covering the Triassic-Jurassic interval were studied in details. On the base of the macro- and microfossil assemblages from the subtidal facies, four informal units have been recognized along the studied section. Unit R1 (at the base, 111 m thick) is dominated by large megalodonts, r…

Triassic/Jurassic boundary in peritidal carbonates from western Tethys

2016

A carbonate platform from the western margin of the Ionian Tethys has been investigated for biotic and geochemical variations across the Triassic/Jurassic boundary (TJB). The section of Mount Sparagio (north-western Sicily) exposes a peritidal succession of Rhaetian-Hettangian age with a thickness of about 400 m. The peritidal sediments are organized in metre-scale shallowing upward cycles formed by subtidal, intertidal and supratidal facies. Along the section, the subtidal facies vary from bioturbated mud/wackestones with rare mollusc shells, to Megalodont-rich wacke/packstones to, more rarely, coral bafflestones, most likely as response to variations of the accommodation space and water e…

A facies distribution model controlled by a tectonically inherited sea bottom topography in the carbonate rimmed shelf of the Upper Tithonian–Valangi…

2016

The Upper Tithonian–Valanginian shallow-water carbonates outcropping in the Palermo Mts (NW Sicily) consist of several facies associations reflecting different depositional environments of a carbonate rimmed shelf, pertaining to the Southern Tethyan continental margin. The reconstructed depositional model, based on the sedimentological features, cyclic facies arrangement and biota distribution, shows that a wide protected lagoon, dominated by algae, molluscs and scattered patch reefs, was bordered landward by a tidal flat, where stromatolitic algal mats were cyclically subaerial exposed, and seaward by a marine sand belt and reef complex. Oolitic packstone-grainstone lithofacies, cyclically…

Early Jurassic normal faulting in a carbonate extensional basin: characterization of tectonically driven platform drowning (High Atlas rift, Morocco).

2009

18 pages; International audience; This paper describes a tectonostratigraphic model of the synrift evolution of the Early Jurassic High Atlas rift of Morocco. The model is constrained by mapping of a set of inverted extensional blocks, by facies analysis of carbonate platform and turbiditic to hemipelagic synrift deposits, and by high-resolution (n 3 100 ka) biostratigraphy of the Early Jurassic succession. The chronostratigraphic packages of the High Atlas of Rich vary significantly in thickness, facies and architecture from one tectonic block to another. Our study shows how synrift strain varied in space and time over a long time interval (14 Ma) around the High Atlas rift. Initially, in …