Palaeoenvironmental reconstruction of late Quaternary foraminifera and molluscs from the ENEA borehole (Versilian plain, Tuscany, Italy)

AbstractForaminifera and molluscs from the 90 m deep ENEA borehole (Versilian plain, central Italy) were studied for paleoenvironmental purposes. Palaeontological analyses, integrated with U/Th and radiocarbon data, helped to recognize late Quaternary sea-level changes and supplied results on tectonic mobility of the area. The study highlighted four sedimentary phases. The first phase consists of a shore environment attributed to MIS 7.1. A hiatus corresponding to MIS 6 is hypothesized at the top of this interval. Recognition of the paleo-shoreline of MIS 7.1 at − 72.8 m signifies a vertical displacement due to the extensional tectonics of the Apennine orogenesis. The second phase consists of a transgressive succession with evidence of warm temperatures, which was interpreted as part of the transgression leading to the MIS 5.5 highstand. The third phase includes sub-aerial and lacustrine deposits. Radiocarbon dates and palaeoecological reconstruction led us to attribute this interval to MIS 4, MIS 3 and MIS 2. The fourth phase begins with a lagoon environment attributable to Holocene sea-level rise and ends with marsh episodes, signifying the progradation of the alluvial plain. This reconstruction confirms the hypothesis of tectonic stability for the Versilian area during the Holocene.

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Late Quaternary Deglaciation, Glaciomarine Sedimentation and Glacioisostatic Recovery in the Rivière Nastapoka Area, Eastern Hudson Bay, Northern Québec

Géographie physique et Quaternaire ◽

10.7202/010331ar ◽

2005 ◽

Vol 57 (1) ◽

pp. 65-83 ◽

Cited By ~ 15

Author(s):

Patrick Lajeunesse ◽

Michel Allard

Keyword(s):

Sea Level ◽

Late Quaternary ◽

Phase 1 ◽

Second Phase ◽

Hudson Bay ◽

Silty Clay ◽

Paleoenvironmental Reconstruction ◽

Relative Sea Level ◽

Radiocarbon Dates ◽

Fluvial Terraces

Abstract This study presents a paleoenvironmental reconstruction of deglaciation dynamics and chronology, glaciomarine and postglacial sedimentation, as well as glacioisostatic recovery in the Rivière Nastapoka area, eastern Hudson Bay. Results indicate that the retreat of Québec-Labrador ice was mainly controlled by topography and was marked by four phases. Radiocarbon dates indicate that deglaciation began about 8.3 ka cal. BP and was characterized by a stillstand of the ice margin in the Nastapoka Hills that lead to the deposition of a drift belt in a high relative sea-level (Phase 1). After this stabilisation, the ice margin retreated rapidly eastward in a region of low relief and deposited a drape of silty clay in a falling relative sea-level (Phase 2). A second phase of stabilization of the ice margin lasted until at least 7.2 ka cal.BP on the higher shield peneplaine east of the limit of the Tyrrell Sea (Phase 3). This lead to the deposition of a belt of glaciofluvial deltas in a lower relative sea-level. Following this stillstand, the eastward retreat and subsequent ablation of the ice in central Québec-Labrador generated meltwater that transported large volumes of glacial sediments by fluvial processes and downcutting of fluvial terraces in previously deposited glaciofluvial and marine sediments (Phase 4). Glacioisostatic rebound reached 0.07 m/yr during the early phase of deglaciation and decreased to 0.04 m/yr between 6 and 5 ka cal. BP and 0.016 m/yr in the last 1000 years.

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Relative sea-level changes in crete: reassessment of radiocarbon dates from Sphakia and west Crete

The Annual of the British School at Athens ◽

10.1017/s0068245400017378 ◽

2002 ◽

Vol 97 ◽

pp. 171-200 ◽

Cited By ~ 11

Author(s):

Simon Price ◽

Tom Higham ◽

Lucia Nixon ◽

Jennifer Moody

Keyword(s):

Sea Level ◽

Late Antiquity ◽

Isotopic Fractionation ◽

Sea Level Changes ◽

Relative Sea Level ◽

Radiocarbon Dates ◽

Sea Levels ◽

Catastrophic Earthquake ◽

Radiocarbon Data ◽

Calendar Dates

This article is concerned with the recognition and dating of Holocene relative sea-level changes along the coast of west Crete (an island located in the active Hellenic subduction arc of the southern Aegean) and in particular in Sphakia. Radiocarbon data for changes in sea levels collected and analysed previously must (a) be recorrected to take into account isotopic fractionation, and (b) recalibrated by using the new marine reservoir value. These new radiocarbon dates are analysed using Bayesian statistics. The resulting calendar dates for changes in sea level are younger than previously assumed. In particular the Great Uplift in western Crete in late antiquity must be dated to the fifth or sixth century AD, not to AD 365. Moreover, recent work on tectonics suggests that the Great Uplift need not have been accompanied by a catastrophic earthquake. Finally, we consider the consequences of the Great Uplift for some coastal sites in Sphakia.

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Late Quaternary sea-level changes along the Tyrrhenian coast near Orbetello (Tuscany, central Italy): palaeoenvironmental reconstruction using ostracods

Marine Micropaleontology ◽

10.1016/s0377-8398(99)00023-7 ◽

1999 ◽

Vol 37 (3-4) ◽

pp. 289-311 ◽

Cited By ~ 59

Author(s):

I. Mazzini ◽

P. Anadon ◽

M. Barbieri ◽

F. Castorina ◽

L. Ferreli ◽

...

Keyword(s):

Sea Level ◽

Late Quaternary ◽

Central Italy ◽

Sea Level Changes ◽

Palaeoenvironmental Reconstruction

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Transgressions and regressions: a model for the influence of tectonic subsidence, deposition and eustasy, with application to Quaternary and Carboniferous examples

Geological Magazine ◽

10.1017/s0016756800013819 ◽

1990 ◽

Vol 127 (2) ◽

pp. 117-128 ◽

Cited By ~ 34

Author(s):

R. E. Ll. Collier ◽

M. R. Leeder ◽

J. R. Maynard

Keyword(s):

Sea Level ◽

Late Quaternary ◽

Sediment Accumulation ◽

Vertical Displacement ◽

Sea Level Changes ◽

Stratigraphic Sequence ◽

Upper Carboniferous ◽

Orbital Parameters ◽

Rates Of Change ◽

Milankovitch Orbital

AbstractThe position of a coastline in time and space is determined by (1) the vertical displacement and/or tilting of the depositional surface, (2) the rate of sediment accumulation or erosion across that surface, and (3) variation of sea-level. All three rates of change may vary through time. We present computer simulations of coastline movements that illustrate the interaction of the above variables, with (1) and (2) held at various defined levels whilst (3) is varied according to the late Quaternary glacio-eustatic sea-level curve. The Corinth Canal section in central Greece exposes uplifted late Quaternary coastal transgressive cycles, each of which may be related to a radiometrically dated, c. 100 ka duration, cycle of sea-level change. Observed stratigraphic sequence geometries are predicted by forward modelling based on the known glacio-eustatic history over the last 430 ka. Milankovitch orbital parameters are calculated for the Carboniferous period. The obliquity and precession parameters are found to have been significantly shorter than at present. A simulation is presented of the effects of sea-level changes across low gradient, fluvio-deltaic environments such as existed in northern England and other parts of the Laurentian continental margin during Upper Carboniferous time.

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Zur relativen und absoluten Geochronologie der Reliefentwicklung an der Küste des mittleren Südwestafrika

E&G Quaternary Science Journal ◽

10.3285/eg.26.1.15 ◽

1975 ◽

Vol 26 (1) ◽

pp. 241-250

Author(s):

Friedrich Wieneke ◽

Uwe Rust

Keyword(s):

Sea Level ◽

Late Quaternary ◽

Coastal Region ◽

Sea Level Changes ◽

Namib Desert ◽

Radiocarbon Dates ◽

Tectonic Movements

Abstract. Results concerning Quaternary geomorphic events in Coastal Namib Desert are presented. We found two high stands and one low stand of the sea level. We obtained radiocarbon dates of Intra-wurm age (ca. 26 000 B.P.) for the younger one of the high stands. This is a eustatic high stand. Late Quaternary tectonic movements of the coastal region have to be considered. The sea level changes are linked to stages of terrestrian morphogenesis. The high stands of the sea level correspond with „arid", the low stands with „humid" environments.

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Late Quaternary Sea Level Changes on Brock and Prince Patrick Islands, Western Canadian Arctic Archipelago

Géographie physique et Quaternaire ◽

10.7202/032973ar ◽

2007 ◽

Vol 48 (1) ◽

pp. 69-84 ◽

Cited By ~ 12

Author(s):

Douglas A. Hodgson ◽

Robert B. Taylor ◽

John G. Fyles

Keyword(s):

Arctic Ocean ◽

Sea Level ◽

Late Quaternary ◽

The Arctic ◽

Sea Level Changes ◽

The South ◽

Radiocarbon Dates ◽

The North ◽

The Arctic Ocean ◽

Ice Loads

ABSTRACT Emerged shorelines are few and poorly defined on Prince Patrick and Brock islands. The sparse radiocarbon dates show emergence of only 10 m through the Holocene on the Arctic Ocean coast, increasing to 20 m 100 km to the east. Hence, from Brock Island, representative of westernmost coasts, the sea level curve since the latest Pleistocene has a very low gradient, whereas on eastern Prince Patrick Island the curve takes the more typical exponential form. A decline in isobases towards the west is thus registered. Drowned estuaries, breached lakes, and coastal barriers, particularly in southwest Prince Patrick Island, suggest that the sea is now transgressing at a rate that decreases towards the north end of the island, hence there is also a component of tilt to the south. Delevelling is assumed to result from undefined ice loads, but may have a tectonic component. The sole prominent raised marine deposit is a ridge probably built in a period of more mobile sea ice, possibly at a time of stable or slightly rising sea level in the middle or early Holocene. It winds discontinuously along several hundred of kilometres of the shores of the Arctic Ocean and connecting channels, declining to the south.

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