The present study retraces the evolution of the delphino-helvetic basin from the Kimmeridgian to the Valanginian in the area of the Bornes and Platé massifs (Haute-Savoie, France). Biostratigraphic correlations demonstrate the importance of submarine erosion affecting the sedimentation in the northern Subalpine mountains between the Upper Tithonian and the Middle Berriasian. The distribution of bioclastic sediments (very abundant in the Lower Berriasian and at the Berriasian-Valanginian boundary) is controled by paleoslopes which strike NE-SW and dip NW or SE. Sedimentological analysis indicates the existence of a bioclastic source area located to the NE of the study area. Detailed description of six sections allows to illustrate and interpret the mode of transportation and emplacement of the major types of resedimented deposits, which up to now have been termed «pseudo-breccias» or «intraformational breccias».