The project to redevelop the Angoulême station district (Îlot Renaudin) motivated the prescription of a preventive archeological search, which revealed several indices of recent Azilian, Laborian then mesolithic and neolithic settlements. The studied area concerns the connection to the east of the lower slope of the front of the Turonian cuesta of Angoulême on the left bank of the alluvial plain of the Charente to the west. A deep test pit in the western part of the plot permitted to cross a large closed depression of about 300 m² and 5 m depth. Two additional perpendicular transects were made to describe the nature and the geometry of this Lateglacial-Holocene transition deposits that fill this depression directly above the Laborian level (site effect). We observed two sedimentary groups, consisting (i) in the lower part, rhythmic levels of pseudo-peat greyish tuffy clayey limestone silts, dated at the bottom by 14C at 9,940 ± 40 BP. These features reveal a low-energy sedimentation and a water-filled environment. The fluctuation of the water table in the depression forced the Laborian groups to move up their occupation zones on the slope. These changes are visible from a geological point of view and also from a typo-technological point of view on the lithic material. Thus, this morpho-sedimentary dynamic has conditioned the spatial organization of the successive settlements. Malacological and palynological studies should clarify these interpretations and provide further paleoenvironmental information on successive occupations. (ii) This lower group is sealed by a powerful tufa deposit (protective position) dated at 7,800 ± 40 BP. The geometry of the upper tufa deposits shows a feeding from the cuesta. This configuration is ideal for the preservation of terrestrial molluscs and the geochemical study (δ18O and δ13C) for paleoclimatic reconstitution in relation with Mesolithic and Neolithic settlements.