Search results for "sea level"
showing 10 items of 123 documents
SEA-LEVEL AND CLIMATIC CHANGES DURING THELAST 41,000 YEARS IN THE OUTER SHELF OF THE SOUTHERN TYRRHENIAN SEA: EVIDENCE FROM FORAMINIFERA AND SEISMOST…
2012
Submerged speleothems and sea level reconstructions: a global overview and new results from the Mediterranean Sea
2021
This study presents a global overview of the submerged speleothems used to reconstruct paleo sea levels and reports new results from two stalactites collected in the Mediterranean Sea. Coastal cave deposits significantly contributed to the understanding of global and regional sea-level variations during the Middle and Late Quaternary. The studied speleothems cover the last 1.4 Myr and focused mainly on Marine Isotope Stages (MIS) 1, 2, 3, 5.1, 5.3, 5.5, 7.1, 7.2, 7.3 and 7.5. The results indicate that submerged speleothems represent extraordinary archives that can provide detailed information on former sea-level changes. The two stalactites collected in the central Mediterranean Sea, at Fa…
Reply to comment by C. Morhange, C. Flaux, P.A. Pirazzoli, M.B. Carre on “Holocene Sea level Change in Malta”
2013
The pits of Birzebbugia are located near the present-day mean sea level, and some are partially submerged. They were dated using pottery discovered in an archaeological site close to the coast, dated to the Bronze Age (Zammit, 1928; Abela, 1999). As they have been interpreted as sites for the retting of flax, during their utilization they should have remained dry and the sea could not submerge them. This is the reason why these structures are not directly related to the sea level, as suggested by Biolchi et al. (2011), so they represent an upper limit.
Vermetid reefs in the Mediterranean Sea as archives of sea-level and surface temperature changes
2011
Vermetid reefs are among the most important bioconstructions in the Mediterranean Sea, with a distribution restricted to the warmest part of the basin. Their structure, and vertical and geographical distribution make them good biological indicators of changes in sea level and sea-surface temperature over the last two millennia.
Modalites sequentielles de la transgression aaleno-bajocienne sur le sud-est du Bassin parisien
2000
Abstract Sedimentologic, biostratigraphic and diagenetic studies made on Middle Aalenian to Lowermost Bathonian deposits in 25 outcrops of the Burgundy High (southeastern Paris basin) lead to a sequence stratigraphy subdivision of the early Dogger record into 7 third order depositional sequences. These sequences make up a second-order transgressive phase whose lower limit is a tectonically enhanced unconformity (the Mid-Cimmerian unconformity), associated with a large scale uplift during the Upper Toarcian and the Lower Aalenian. In the largest outcrops, where the geometry of sedimentary bodies is observable at the hectometre to kilometre scale, the combination of diagenetic, biostratigraph…
Markers of the last interglacial sea level high stand along the coast of Italy: Tectonic implications.
2006
A compilation of the Marine Isotope Substage (MIS) 5.5 high stand (similar to 125Ka) sites spanning the coastline of Italy allows a picture of the vertical displacement pattern affecting the Central Mediterranean coasts since the Late Pleistocene to be drawn. For each of the 246 listed sites, the accurate elevation of the high stand is defined through well-known markers. Coupled with a refilled age assessment locally Supported by new radiometric dating, these markers provide robust constraints oil deformation. Significant alongshore differences in site elevation between + 175 and - 125 m a.s.l. resulted from the interplay of regional and local tectonic processes, including faulting and volc…
Assessing vermetid reefs as indicators of past sea levels in the Mediterranean
2020
Abstract The endemic Mediterranean reef building vermetid gastropods Dendropoma petraeum complex (Dendropoma spp) and Vermetus triquetrus develop bio-constructions (rims) on rocky shorelines at about Mean Sea Level (MSL) and are therefore commonly used as relative sea-level (RSL) markers. In this study, we use elevations and age data of vermetid reefs to (1) re-assess the vertical uncertainties of these biological RSL indicators, and (2) evaluate the vertical growth rates along a Mediterranean east-west transect, in attempt to explain the differences found in both growth rates and uncertainties. In Israel, Differential Global Positioning System (DGPS) and laser measurements relative to the …
The Brolo Island, a lentil in the “Ocean”
2010
The north-eastern Sicily coast reflects the effects of Holocene active tectonics associated to subduction system of Ionian crust beneath the Calabrian arc (CAPUTO et alii, 1970; WESTAWAY, 1993, DOGLIONI et alii, 1999). The latter, characterized by a stack of crystalline rock and its sedimentary cover, is the highest structural element in the Sicily chain. The Calabrian arc is a region that records one of the major Quaternary vertical tectonic movement in the whole Mediterranean basin. This uplift, well documented from Last Interglacial, is expressed as vertical variation of the height of the Quaternary marine terraces inner margin that characterize the north-eastern Sicily coast. The uplift…
Eustatic and oceanographic control on sedimentary evolution of middle-late Quaternary shelf margin-to-upper slope deposits on the Egadi Islands offsh…
2016
During the past decades a number of sequence stratigraphy studies illustrated how, during Quaternary, interaction between sea level changes and sediment supply controlled the depositional evolution along continental margins, giving a cyclic signature to the sedimentary infilling. However, as both deposition and erosion are processes ultimately controlled by balance between environmental energy and sedimentary influx, also the oceanographic regime takes part in controlling the sedimentary growth along the continental margin. This is exactly what occurs on physiographic settings as islands offshore areas, where bottom currents can be very energetic. In the western Sicily offshore, southwards …
Future coastal hazard scenarios. A case study in NE Sicily (Italy)
2012
The coastal dynamics is the result of several causes that contribute to change the balance of beach deposits over time. The beach system is not always able to maintain coastal balance: the factors contributing to this phenomenon are to be found in both natural and anthropogenic spheres. In this context we present the analysis of marine geology and coastal geomorphological data of a sector between Rocca di Caprileone and Tindari (north-eastern Sicily) with the aim to: i) determine their onland-offshore area relationships, ii) analyze which natural features may contribute to coastal retreat, iii) present coastal hazard scenarios. Until fifty years ago the natural balance of this coastal area …