EC-PROMESS 1 project: stratigraphic synthesis of the hole PRAD1-2 (Middle Pleistocene-Holocene of the Central Adriatic).

We present the stratigraphic synthesis of the borehole PRAD1-2 (EC-PROMESS 1
project) drilled in 186 m water depth on the western flank of the Central Adriatic basin.
The borehole recovered ca. 71 m of continuous sedimentary sequence. The stratigraphy
is based on the ecobiostratigraphy of planktic and benthic foraminifera, O and C
stable isotope record, magnetic parameters, seismic stratigraphy, lithology, grain-size
and XRF data. Based on semi-quantitative and quantitative analysis of the planktic
and benthic foraminifera assemblages, we recognize a succession of glacial and interglacial
intervals referred to MIS 1 to MIS 10. Interglacial periods are characterised by
abundant planktic foraminifera. Glacial periods show very scarce or absent planktic
foraminifera assemblages, and a generally very rich benthic foraminifera assemblage
indicative of a mid- to inner-shelf environment.
The shallowest paleo-bathymetry (inner shelf) is reached during the MIS 10 when
coarser grain-size values are observed. Several intervals are characterised by dark and,
in some cases, laminated sediments, as well as by low values of the 18O and 13C, and
low Anhysteretic Remanent Magnetization values. These intervals are dominated by
(deep-) infaunal benthic foraminifera assemblages indicating low-oxygen bottom waters,
and in some particular intervals the sediment is even void of benthic fauna. During
these intervals Neogloboquadrinids or Globigerinoides ruber (pink variety with
thin and inflated test) dominate the planktic assemblage during glacial or interglacial
periods, respectively. These intervals are also associated with abrupt decreases in the
Sortable Silt fraction. These intervals can be considered as the Central Adriatic equivalents
of the Eastern Mediterranean sapropels S1, S3, S4, S5, S6, S7, S8, S9, Si and
S10 and they can be considered as control points for the chronology of the borehole.
The magnetic parameters also allowed recognise a geomagnetic excursion between
MIS 7 and MIS 6 that has been referred to the Iceland Basin Excursion (about 188 kyr
B.P.).
Acknowledgements: PROMESS 1 is an European Community funded project of the
5th Framework Programme (EVR1-2001-41). It belongs to the OMARC cluster of
projects. It is a companion project of the joint Euro-US "EUROSTRATAFORM"
project. See http://promess1.wdc-mare.org/