The late Messinian Lago-Mare episode in the central Mediterranean Basin: new data from the onshore Mondragone 1 well.

The Mondragone 1 well, drilled in 1968 by Agip, for hydrocarbon exploration, is located in the plain of the Garigliano River, at about 3 km to the east of Cellole village (lat. 41° 12’ 17”, long. 13° 48’ 52”). The Mondragone 1 well cut across siliciclastic fine-to-coarse-grained upper Miocene-Quaternary deposits, for a total depth of 2002 m.Drilling the Mondragone 1 well, fourteen sediments cores have been recovered from 495 m down to 2000 m; SP and resistivity logs have been also recorded (fig. 1).At 495 m depth, dipping strata measurements on sediment cores have shown a strong angular unconformity between 'Plio-Pleistocene coarse-grained deposits (17-25° dip) and the underlying fine- and coarse-grained upper Miocene deposits (40-55° dip). These latter deposits from –675 down to –1570 m consist of four 60-70 m-thick pebble horizons interbedded with clays, silts, marls and sands. From a depth of -1570 m to the bottom of the hole, sandstones with sulphatic-clayey cement were drilled. Moreover, from –1800m down to the bottom (-2002 m), the Mondragone 1 well drilled through sandstones with anhydrite-filled veins.Below the 675 m-depth angular unconformity the recovered samples (sediment cores 3-14) showed Paratethyan ostracods assemblages from –800 down to –2000 m-depth (Agip-Dimi, 1969, revised by Gliozzi in Cipollari et al., 1999). The Mondragone 1 sediment cores have been recently re-sampled and analysed. This paper deals both with the results of the biostratigraphical analyses performed on the Mondragone 1 re-sampled sediment cores and with the significance of the Mondragone 1 well data in the central Mediterranean scenario during the late Messinian Lago-Mare episode. Moreover, data from seismic lines have been used to reconstruct the geometry and the structural setting of the Garigliano Basin during the latest Messinian.