The structure and evolution of the Central Kerguelen Plateau (CKP), located between 54°-57°S and 61°-84°E, is derived from the seismic stratigraphic interpretation of multichannel seismic data and from Ocean Drilling Program results at Site 747. The CKP formed 120-110 m.y. ago by excessive volcanic activity at the axis of the spreading ridge that separated India from Antarctica. At 72 Ma, a major pre-rift tectonic episode stretched the basement of the CKP in an east-west direction; the 77°E Graben consists of several rift units, somewhat similar to the structure observed in the East African continental rift system. At 42 Ma, the breakup between the Kerguelen Plateau and Broken Ridge was accompanied by a period of nonsedimentation of about 15-m.y. duration. After the breakup, the sedimentation was generally continuous but evolved during the Pliocene-Pleistocene in response to climate changes.

The evolution of the Raggatt Basin in the Southern Kerguelen Plateau, since the Late Cretaceous, was deduced from seismic stratigraphic interpretations of the multichannel seismic data and Ocean Drilling Program results at Sites 748 and 750. Synthetic seismograms were built using in situ and corrected core velocity values. Corrections were based on Wyllie's law, and exponential variations of porosity were calculated from logging data at Site 750. The synthetic seismograms in conjunction with the seismic sections allowed us to correlate the lithologic units and the seismic sequences.After the emplacement of oceanic basaltic basement at 110 Ma, the Late Cretaceous history of the Raggatt Basin was controlled by two rifting episodes at 88 Ma to the east and at 66 Ma to the west. The first rifting episode, with an axis of extension striking northwest-southeast, formed the eastern flank of the Southern Kerguelen Plateau. The second rifting episode, along a north-south axis, formed the 77°E Graben. At 45-42 Ma, the separation by seafloor spreading of the Kerguelen Plateau-Labuan Basin and Broken Ridge-Diamantina Zone marks a third rifting episode, which was recorded on the Southern Kerguelen Plateau by erosion.

During Leg 120, weather conditions and time constraints restricted logging operations to Sites 747 and 750; only the seismic-stratigraphic combination was run at these sites. For some intervals, the sonic digital tool produced extremely noisy velocity logs that made interpretation of the data very difficult, even impossible. Three types of noise were observed: phase skipping, oscillations caused by noncompensated heave, and discrete aberrant velocity values. The heave-related oscillations recorded on the velocity logs were eliminated by deriving a simple model simulating the tool movement. The aberrant velocity values, essentially caused by failures in recording the signal from one of the two transmitters, were eliminated by inspection of the individual waveforms using an interactive software package. This software program was also used to pick the compressional arrival time. A composite velocity log accounting for all these corrections and complemented for the unlogged part of the hole with the core-measured velocities was used to derive a synthetic seismogram at Site 747. The synthetic seismogram was correlated with a multichannel seismic reflection profile and the lithologic units, which allowed us to define four seismic sequences that could be identified with the K2-K3, P1-P2, PN1, and NQ1 sequences of the Raggatt Basin in the Southern Kerguelen Plateau.

ENGJE LL PRENJASI, FATMIR FEZGA and VI L S ON BAR EGil and Gas Institute, Fier, A lba rriaThree following tectonic units are the main integral parts of the Western Albania .1) Sazani zone or Pre-Apulian platform represents a big monocline composed of the Cretaceous carbonates that dips gradually northeastwards under Albania Thrust Belt .2) Albania'Thrust Belt represents a tectonic assemblage composed of several tectónic zones that Zie southeast-no rthwestwards in direct no rthern continuation of the Hellevides .Thé Thrust Belt consists of four rocky formations as follów : a) The Carbonate formation ranges from the Upper Triassic to the Eocene age . They sometimes are in#érrupted by the evaporitc rocks of the Upper Triassic age that have emerged from the ir normal position owing to a common effect of tectonic forces and diapirism phenomenon .b) The Flysch formation of the Oligocene ' age that often increases considerably its thickness, due to a verg complex common effect of lithological changes, téctonic folding and clay diapirism.

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