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New high-quality multibeam and seismic data image the western slope of the Great Bahama Bank and the adjacent fl oor of the Straits of Florida. The extensive survey reveals several unexpected large-and small-scale morphologies. These include bypass areas, channel-leveelobe systems, gullied slopes, and products of slope instabilities at various scales, including long slump scars at the lower slope and mass transport complexes that extend ~30 km into the adjacent basin fl oor. The toe of the slope is irregularly covered with deep-water carbonate mounds. The abundance of the individual morphological features varies from north to south. From 26°00′N to 25°20′N, the slope is dissected by numerous deep canyons that abruptly end southward, where the slope is characterized by a smooth lower portion and small regularly spaced furrows in its upper part. Further south, two long (25-50 km) scars document instability at the lower slope. One of these scars is the source area of a large mass transport complex. In addition to this large-scale feature, several types of gravity-induced sedimentary processes are revealed. Most of the morphologies and inferred processes of this carbonate system are similar to those observed in siliciclastic systems, including mass transport complexes, gravity currents initiated by density cascading, and overspilling channeled turbidity currents. For the fi rst time, a clear asymmetric channel-levee system has been identifi ed along the slope, suggesting similitude in sorting processes between carbonate and siliciclastic systems and enhancing the reservoir-bearing potential of carbonate slopes. Notable differences with siliciclastic systems include: the lack of connection with the shallow and emerged part of the system (i.e., bank top), and the small size of the sedimentary system.

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A 220-meters thick carbonate-dominated succession has been deposited in shallow-water, saline lake environments during the Lower to Middle Priabonian (MP17A-MP18 mammal zones) in the Saint-Chaptes Basin (south-east France). The palaeoenvironmental, paleoclimatic and palaeogeographic significance of such salt lake carbonates has been deciphered on the basis of a multi-proxy analyses including 1) depositional and diagenetic features, 2) biological components (molluscs, benthic foraminifera, characean gyrogonites, spores and pollens), 3) carbon and oxygen stable isotopes, 4) trace elements and 5) clay mineralogy. Five stages of lacustrine system evolution have been identified: 1) freshwater closed lake under dry climate (unit U1); 2) fresh to brackish water lacustrine deltaic system with a mixed carbonate-siliciclastic sedimentation under relatively wet climatic conditions (unit U2); 3) saltwater lacustrine carbonate system under humid climatic setting (unit U3); 4) evaporitic lake (unit U4); and 5) closed lake with shallow-water carbonate sedimentation under subtropical to Mediterranean climate with dry seasons (unit U5). Upper Eocene aridification is evidenced to have started as early as the earliest Priabonian (unit U1: MP17A mammal zone). A change from humid to dryer climatic conditions is recorded between units U3 and U4. The Lower-Mid Priabonian saline lake is interpreted as an athalassic (inland) lake that have been transiently connected with neighboring salt lakes influenced by seawater and/or fed with sulfates deriving from recycling of evaporites. Maximum of connection with neighboring salt-lakes (Mormoiron Basin, Camargue and Central grabens, Hérault Basin) likely occurred during unit U3 and at the base of unit U5. The most likely sources of salts of these adjacent basins are: 1) Triassic evaporites derived from salt-diapirs (Rhône valley) or from paleo-outcrops located east of the Durance fault or offshore in the Gulf of Lion; or 2) marine incursions from the south, through Paleogene grabens in the Gulf of Lion.