The early Toarcian oceanic anoxic event, as defined by both relatively high TOC values and ammonite and nannofossil
biostratigraphy, is clearly synchronous across Europe and undoubtedly prove to be so in global context, given its recent investigation in Argentina [12, 26-28].
The sediments were also examined for palynomorphs, planktonic foraminifera, and calcareous nannofossils
, even though few were expected to be found.
(2011): The uppermost Middle and Upper Albian succession at the Col de Palluel, Hautes-Alpes, France: An integrated study (ammonites, inoceramid bivalves, planktonic foraminifera, nannofossils
, geochemistry, stable oxygen and carbon isotopes, cyclostratigraphy).
As a result from the ramp morphology and controlled by regional tectonics and sea level changes, the thickness of these units increases towards the west, which are biostratigraphically well constrained due to the abundance of benthic and nektonic fauna, namely ammonites and calcareous nannofossils
(Silva et al., 2011; Duarte et al., 2010; Oliveira et al., 2007; Dommergues and Mouterde, 1987; Mouterde, 1953, 1967) (Fig.
(1993): Biochronology of the terminal Cretaceous calcareous nannofossil
Zone of Micula prinsii.
The ranges of more than 1100 bioevents, planktic and benthic foraminifers, nannofossils
, dinoflagellates, ammonites, bivalves, echinoids, calcareous algae, magnetochrons, geochemical events and sequence stratigraphic markers are defined in this database (Scott et al., 2000; and Aguilera-Franco, 2000).
(in press ): Correlation of the Pliocene-Quaternary foraminiferal and nannofossil
zonations in the Northern Atlantic.
(1992): Correlation of Late Cretaceous calcareous nannofossil
zones with ammonite zones and planktonic Foraminifera: the Austrian Gosau sections.
In addition to earlier works (Maurrasse et al., 1979/1985; 1982b) more detailed studies of planktonic foraminiferal and nannofossil
assemblages allowed to distinguish a complete biostratigraphic succession across the K/T transition (Lamolda et al., 1997b).
To recognise temperature changes, all nannofossil
taxa have been divided according to their association with warm or cold waters.
These syn-rift deposits are unconformably overlain by marine calcareous muds, consisting of nannofossil
oozes and nannofossil
chalks, ranging in age between Berriasian--lower Valanginian (Hole 1069A), Valanginian--Barremian (Hole 1068A) and late Aptian (Hole 1070A).