The Linkage between Alluvial and Coeval Nearshore Marine Successions: Evidence from the Late Quaternary Record of the PO River Plain, Italy

  1. Michael D. Blum2,
  2. Susan B. Marriott3 and
  3. Suzanne F. Leclair4
  1. Alessandro Amorosi and
  2. Maria Luisa Colalongo

Published Online: 17 MAR 2009

DOI: 10.1002/9781444304350.ch15

Fluvial Sedimentology VII

Fluvial Sedimentology VII

How to Cite

Amorosi, A. and Colalongo, M. L. (2009) The Linkage between Alluvial and Coeval Nearshore Marine Successions: Evidence from the Late Quaternary Record of the PO River Plain, Italy, in Fluvial Sedimentology VII (eds M. D. Blum, S. B. Marriott and S. F. Leclair), Blackwell Publishing Ltd., Oxford, UK. doi: 10.1002/9781444304350.ch15

Editor Information

  1. 2

    Baton Rouge, Louisiana, USA

  2. 3

    School of Geography and Environmental Management, University of the West of England, Bristol BS16 1QY, UK

  3. 4

    Department of Earth and Environmental Sciences, Tulane University, Dimwiddie Hall, New Orleans, LA 70118, USA

Author Information

  1. Università di Bologna, Dipartimento di Scienze della Terra e Geologico-Ambientali, Via Zamboni 67, 40127 Bologna, Italy

Publication History

  1. Published Online: 17 MAR 2009
  2. Published Print: 15 FEB 2005

Book Series:

  1. Special Publication Number 35 of the International Association of Sedimentologists

Book Series Editors:

  1. Ian Jarvis

Series Editor Information

  1. School of Earth Sciences and Geography, Centre for Earth and Environmental Science Research, Kingston University, Penrhyn Road, Kingston-upon-Thames KT1 2EE, UK

ISBN Information

Print ISBN: 9781405126519

Online ISBN: 9781444304350

SEARCH

Keywords:

  • quaternary fluvial systems;
  • linking alluvial and coeval nearshore marine successions;
  • linkage between fluvial and marine deposits in Po basin;
  • stratigraphical architecture of Holocene deposits of Po coastal plain;
  • non-arboreal pollen (NAP);
  • key surfaces for sequence stratigraphical interpretation;
  • sequence boundary (SB), the transgressive surface (TS) and maximum flooding surface (MFS);
  • Galloway's model - maximum flooding surface chosen as bounding surface

Summary

Detailed facies analysis of cores, up to 200 m long, within the Late Quaternary fluvial to shallow-marine succession of the Po River Plain, reveals characteristic cyclic changes in lithofacies and channel stacking pattern. Transgressive surfaces are readily identifiable, showing a greater extent and correlation potential than sequence boundaries or maximum flooding surfaces. Stacked transgressive–regressive (T–R) sequences, 50–100 m thick and spanning time intervals of about 100 kyr, form the basic motif of the Late Quaternary Po Basin fill. At relatively seaward locations (coastal sections), the lower parts of these 4th-order cycles show coastal-plain aggradation and rapid shoreline transgression (retrograding barrier–lagoon–estuary systems), forming thin transgressive systems tracts (TST). Transgressive deposits are overlain by characteristic shallowing-upward successions, related to delta and strandplain progradation (highstand systems tracts or HST). Subsequent long phases of sea-level fall are recorded by exceptionally thick (up to 60 m) successions of interbedded alluvial and coastal-plain deposits (falling-stage (FST) and lowstand (LST) systems tracts). At landward locations, within non-marine strata, bounding surfaces of T–R sequences are marked by abrupt facies changes from amalgamated fluvial-channel gravel and sand, formed mostly at lowstand conditions, to mud-dominated floodplain deposits, with isolated channel bodies and organic horizons (transgressive alluvial deposits or TST). This section grades upward into thick alluvial plain deposits, showing increased channel clustering and sheet-like geometries (regressive alluvial deposits, including HST, FST and LST). The sharp lower boundaries of T–R sequences identified within the alluvial sections can be traced physically into the transgressive surfaces recognized at seaward locations. The transgressive surfaces are characterized by well identifiable pollen assemblages. Correlation with the marine oxygen-isotope record documents strict relationships between T–R sequences and glacial–interglacial cycles, showing that transgressive surfaces correlate invariably with the onset of warm-temperate (interglacial) phases.