Search results for "BASIN"

The morphological diversity within a species can obscure the correct identification

2022

Critical points of various diagnostic characters and a paucity of information relating to the geographical distribution of several marine species can hinder real species delimitation, particularly if they are supposed to be cosmopolitan. Such constraints characterize many amphipod species and are mainly due to the variation in morphological characters during growth. Specifically, the benthic filter-feeding corophiid Cheiriphotis mediterranea Myers, 1983 displays different shapes for the male gnathopod 2 as it grows. This variation has hitherto never been described but an extensive sampling has provided us with the opportunity of studying it in detail. More than six thousand individuals, bel…

The fossil rodent faunas of the localities Alcoy 2C and 2D (Alcoy Basin, Spain). Implications for dating the classical locality of Alcoy-Mina

2014

In the Gormaig area (Alcoy basin, SE Spain) a number of fossil mammal localities are known, of which only the classic site of Alcoy-Mina, known since the mid-19th century, has yielded remains of macrofauna. In the vicinity of this site are the localities of Alcoy-2C (AL2C) and Alcoy-2D (AL2D), probably representing the levels of Alcoy-Mina. The faunal assemblage allows dating the AL2C and AL2D localities as Early Pliocene (end of the Early Ruscinian or early-late Ruscinian boundary, MN14-MN15). Several taxa (Pliopetaurista and Glis) are thought to have affinities for humid and close biotopes. En el área del Gormaig (cuenca de Alcoy, SE España), se conocen toda una serie de yacimientos de ma…

Fast extension but little exhumation: the Vari detachment in the Cyclades, Greece

2003

Markedly different cooling histories for the hanging- and footwall of the Vari detachment on Syros and Tinos islands, Greece, are revealed by zircon and apatite fission-track data. The Vari/Akrotiri unit in the hangingwall cooled slowly at rates of 5–15 °C Myr−1 since Late Cretaceous times. Samples from the Cycladic blueschist unit in the footwall of the detachment on Tinos Island have a mean zircon fission-track age of 10.0±1.0 Ma, which together with a published mean apatite fission-track age of 9.4±0.5 Ma indicates rapid cooling at rates of at least ∼60 °C Myr−1. We derive a minimum slip rate of ∼6.5 km Myr−1 and a displacement of <∼20 km and propose that the development of the detach…

Spatial analysis techniques for mapping the annual surface runoff in Sicily under the Budyko’s framework

2016

This work shows a new approach, based on the Budyko framework, for mapping the mean annual surface runoff and deriving the probability distribution of the annual runoff in arid and semi-arid watersheds. We analytically provide the annual runoff distribution as the derived distribution of annual rainfall and potential evapotranspiration. The simulated long-term annual runoff and its distribution have been compared with historical records at several gauged stations, obtaining satisfactory matching.

Assessing sediment connectivity in dendritic and parallel calanchi systems

2019

Abstract Calanchi, a type of Italian badlands created by a combination of water erosion processes and environmental constraints controlling their development, is a striking example of long-term landscape evolution. Sediment connectivity can be defined as the degree to which a system facilitates the fluxes of sediments through itself. The goal of this research is testing the use of simple morphometric variables for assessing sediment connectivity of calanchi landforms distinguishing between dendritic and parallel systems. For detecting the morphological characteristics controlling the sediment connectivity of calanchi basins, literature data (146 calanchi basins) and measurements carried out…

The origin and timing of multiphase cementation in carbonates: Impact of regional scale geodynamic events on the Middle Jurassic Limestones diagenesi…

2009

The Middle Jurassic carbonates of the eastern part of the Paris Basin display surprisingly low values of porosity and permeability (Φ < 15‰ and K < 0.5 mD). The main objective of this study is to determine the causes and timing of the cementation that altered the petrophysical properties of these carbonates thereby destroying their potential as oil reservoirs; a fate that did not befall their equivalents in deeper, central parts of the Paris Basin. Using petrographic and geochemical analyses (stable O and C isotopes, Sr isotopes, major elements), we identify six calcitic spar stages, two dolomite stages, and several episodes of fracturing and stylolitization ordered in paragenetic sequence.…

Submarine canyon morphologies in the Gulf of Palermo (Southern Tyrrhenian Sea) and possible implications for geo-hazard

2011

12 pages, 12 figures, 1 table.

Potential Cyclic Steps in a Gully System of the Gulf of Palermo (Southern Tyrrhenian Sea)

2016

Multibeam bathymetric data revealed the occurrence of atrain of bedforms along a gully system in the Gulf of Palermo, Southern Tyrrhenian Sea. The observed gullies, located in the westernmost sector of the Gulf of Palermo, incise the outer shelf at a depth of 120 m and converge at the Zafferano Canyon, connecting to the Palermo Basin at a the depth of 1300 m. Bedforms develop along these gullies and along the thalweg of the canyon, displaying an average wavelength of 200 m, with maximum values of 340 m. Their gully floor location combined with their wave length, upslope asymmetry and crescent shape point to a possible cyclic steporigin of these bedforms. Preliminary numerical modeling sugge…

Carbonate platform-basin systems of Sicily through the Triassic/Jurassic Boundary: Stratigraphic constraints for the paleogeographic reconstructions.

2004

Sedimentology of a Late Quaternary lacustrine record from the south-eastern Carpathian Basin

2021

The Upper Pleistocene geoarchives in the south‐eastern Carpathian Basin are represented predominantly by loess–palaeosol records. In 2015, a 10 m sediment core composed of clay‐rich lacustrine sediments was recovered by vibracoring a dry lake basin located between the Vršac Mountains (Serbia) and the Banat Sands in the south‐eastern Carpathian Basin; a location relevant for placing regional archaeological results in a palaeoenvironmental context. Here, we present results from geoelectrical prospection and a lithostratigraphic interpretation of this sequence supported by a detailed granulometric study supplemented by ostracod analysis. An age model based on luminescence dating is discussed a…