Abstract
On the Mediterranean continental shelves the post-glacial transgressive succession is a complex picture composed of seaward progradations, related to sea level stillstands and/or increased sediment supply to the coasts, and minor flooding surfaces, associated with phases of enhanced rates of sea level rise. Among Late Pleistocene examples, major mid-shelf progradations have been related to the short-term climatic reversal of the Younger Dryas event, a period during which the combination of increased sediment supply from rivers and reduced rates of sea level rise promoted the formation of progradations up to tens-meter thick. While the documentation of coastal and subaqueous progradations recording the Younger Dryas interval is widely reported in literature, the model of compound progradation within transgressive deposits has not yet been proposed. Here we present the documentation of a deltaic system where both delta front sands and related fine-grained subaqueous progradations (prodeltaic to shallow marine) have been preserved. The Paleo Gargano Compound Delta (PGCD) formed offshore the modem Gargano Promontory (southern Adriatic Sea), and is composed of a coastal coarse-grained delta of reduced thickness and a muddy subaqueous clinoform, up to 30 m thick. The PGCD, probably the first worldwide documentation of a compound delta within the transgressive record, provides the opportunity to investigate the processes controlling the formation of a compound delta system during an overall sea level rise and the factors that allowed its preservation. The finding of the PGCD provides the opportunity for a comparison with modern worldwide compound systems. (C) 2015 Elsevier B.V. All rights reserved.
Original language | English |
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Pages (from-to) | 43-59 |
Number of pages | 17 |
Journal | Marine Geology |
Volume | 362 |
Early online date | 28 Jan 2015 |
DOIs | |
Publication status | Published - 1 Apr 2015 |
Bibliographical note
AcknowledgmentsWe are grateful to the Editor for its suggestions, the anonymous reviewer for his detailed comments and suggestions and to the reviewer Liviu Giosan for his comments and suggestion. We thank Captain, the Crew of campaigns and all the researches on board R/V Urania (CNR) that during the last decades acquired chirp sonar profiles and sediment cores. We thank Gwenael Jouet, Bernard Dennielou, and Elda Miramontes García for their insights, and Mickael Rovere and Angelique Roubi for their skilled assistance in calcimeter and grain size analysis at Ifremer GM-LES in Brest. We thank Andrea Gallerani for the X radiography at ISMAR-CNR in Bologna. We thank Alessandra Asioli for her consulting and Elisabetta Campiani and Federica Foglini for their support on GIS. This is ISMAR-CNR contribution number 1857.
Keywords
- Compound delta
- Mediterranean Sea
- Younger Dryas
- Subaqueous clinoform
- Transgressive deposits
- Late Quaternary
- Sediment Accumulation