External Controls on Deep-Water Depositional Systems

The principal objective of the meeting from which this set of papers arose was to gain an overview of the current state of knowledge of the roles and interplays of external controls on deposition in deep marine environments. By external controls we mean allocyclic or allogenic factors, i.e., those that are unrelated to the self-organization of the depositional system (autocyclic or autogenic); principal among these are climate, sea level, sediment supply, and tectonics. One of the big questions that the meeting sought to address concerned the comparability of the recent high-frequency, high-resolution record with the older, generally lower-frequency stratigraphic record of “deep time”; to what extent are the apparent differences a function of resolution, or of comparisons between a glacial and a nonglacial Earth? In fact, as the papers in this volume illustrate, the variability between individual systems, even in Late Glacial time, and the paucity of constraints on older systems makes these questions difficult to answer, but some useful conclusions can be drawn. The papers presented at the meeting were organized into themes that included: overviews of glacial sea-level change, and of climate modeling; external controls on large river-fed submarine fans, including the effects of climate and sea level on the fluvial system itself; influences of climate, sea level, and tectonics on a range of smaller modern systems; deep marine processes; the outcrop record of the pre-Pleistocene Earth; the subsurface record of the pre-Pleistocene Earth; and syntheses. The organization of the volume largely reflects this structure.
Climatic Control on Deposition of Upper Pliocene Deepwater, Gravity-Driven Strata in the Apennines Foredeep (Central Italy): Correlations to the Marine Oxygen Isotope Record
-
Published:January 01, 2009
-
CiteCitation
Gino Cantalamessa, Claudio Di Celma, Maria Potetti, Paola Lori, Petros Didaskalou, Andrea Albianelli, Giovanni Napoleone, 2009. "Climatic Control on Deposition of Upper Pliocene Deepwater, Gravity-Driven Strata in the Apennines Foredeep (Central Italy): Correlations to the Marine Oxygen Isotope Record", External Controls on Deep-Water Depositional Systems, Ben Kneller, Ole J. Martinsen, Bill McCaffrey
Download citation file:
- Share
Abstract
The thick upper Pliocene to lower Pleistocene succession of hemipelagic mudstones of the Marche Apennines foredeep (central Italy) is punctuated by several mostly coarse-grained, cyclic turbidite systems. Integrated and detailed analyses of sedimentary facies, physical stratigraphy, biostratigraphy, and magnetostratigraphy have provided a high-resolution sequence stratigraphic framework for sediments of two of these coarse-grained systems, each resulting from the stack of five deepwater, high-frequency depositional sequences backfilling the mouth and lower reaches of a long-lived submarine canyon. The tight chronostratigraphic control available on these two turbidite systems and encasing hemipelagic sediments allows a precise correlation of the component high-frequency sequences with the Pliocene marine oxygen isotope curve. This reveals that the cyclic arrangement occurred near the Gauss–Matuyama polarity transition and the onset of the Olduvai subchron in response to recurring, obliquity-driven global changes in sea level. Each depositional sequence, 20 to 65 m thick, includes sediments that were deposited by a range of gravity-driven processes, resulting in sedimentary motifs that contain a deep marine record of both glacial and interglacial stages. A typical depositional sequence comprises: (1) a lowstand systems tract composed of cohesionless-debris-flow conglomerates (braided submarine channel complex), which passes down-dip into turbidite sandstones (frontal-splay complex); (2) an overlying transgressive to early falling-stage systems tract composed of a mud-rich masstransport complex of slumped horizons and cohesive-mud-flow pebbly mudstones eventually overlain by a thin interval of hemipelagic mudstones. This stacking pattern records variations in depositional style, and hence, variations in canyon activity during eustatic changes in sea level.
External Controls on Deep-Water Depositional Systems
SEPM Special Publication No. 92 (CD version), Copyright © 2009
SEPM (Society for Sedimentary Geology), ISBN 978-1-56576-200-8, p. 247–259.