MAGNETOSTRATIGRAPHY AND BIOSTRATIGRAPHY O F THE TOARCIAN AMMONITICO-ROSSO FORMATION FROM THE IONIAN ZONE (EPIRUS, GREECE)

Magnetostratigraphic results were obtained from three sections of Ammo nitico-Rosso Formation in Epirus (Greece). These red nodular limestone s display standard magnetic characteristics. Magnetite and haematite a s pigment contribute to the natural remanence. The stable characterist ic magnetic component was recognized by thermal demagnetization in the range of 350-550-degrees-C. Magnetic polarity sequences were establis hed for each section. Few ammonites were found at some levels, mainly in the Middle Toarcian. The conjunction of biostratigraphic and magnet ostratigraphic data allow to propose correlations between the sections studied and with the Toarcian ammonitico-rosso limestones section of Iznalloz (Betic Cordillera. Spain). The extension of the Ammonitico-Ro sso Formation is variable depending on the sections and does not cover the whole Toarcian stage. The appareance of the ''Calcaires a Filamen ts'' Formation succeeding the red nodular limestones seems to be synch ronous over the two distinct paleogeographic units studied through the Ionian basin.