## 4 Results  
The Conero promontory provided a set of data useful for better defining the morphoevolutive implications of the gravity-induced processes and landforms along the coastal zone. The entire coastal slope is affected by landslides of different typologies, which account for erosional landforms at the upslope zone and abundant landslide deposits along the mid- and footslope sites (Figure 1, Figure 2A, Figure 3, and Figure 4). Landslides are predisposed by low persistency of rock mass joints and by strata attitude whose dip is very close to the slope face direction. The largest mass movements surveyed in the area occur in the northern coastal sector, between the Portonovo village and the La Vela sea stack (Figure 1), where two adjacent, large landslides masses can be observed and ascribable to rock-avalanche/slide mechanism [44], as they are associated with wide detachment scars that typify the sharp edge of the coastal cliff and delimit seaward the calcareous ridge top (Figures 1 and 3A). The northern landslide (Portonovo landslide) shows a runout of about 500 m that flowed seaward, accounting for the shaping of a bay where Portonovo village developed. A series of typical compressional ridges characterize the distal zone of this mass movement. The southern landslide (La Vela landslide), on the contrary, shows a truncated toe, though observing the trend and geometry of the contour lines down to \(-10\) m b.s.l., the nearshore morphology of the seafloor indicates that a terminal landslide lobe is still detectable (Figure 1). Figure 3: Landforms and deposits due to gravity along the northern portion of the Conero rocky coast. (**A**) Panoramic view, towards the south, of the Portonovo and La Vela rocky coast (northern coastal sector). (**B**) Toe area of the Vela rockslide. In this sector, a late-glacial stratified slope deposit (i.e., eboulis ordonnee) overlays the landslide deposit. (**C**) Rock avalanche deposit at the toe of the Portonovo landslide exposed along a wave-cut scarp. The inset shows chaotic debris prevalently belonging to the Scaglia Rossa Fm. (SR) and incorporating a marly calcareous boulder belonging to the Marne a Fucoidi Fm. (MF). (**D**) Ridge-top depression in the Portonovo landslide backscatter area. Patches of a thin layer of stratified slope-waste deposits form outcrops along the cliff base (Figures 1 and 2B) and unconformably overlay the chaotic landslide deposits. Stratified slope deposits are widespread within the Umbria-Marche Apennines, even along the coastline [45], principally where bedrock particularly prone to frost shattering, as Maiolica and Scaglia Rossa formations, is exposed. These deposits typify cold, periglacial environments [46] and represent in the Apennine area the termination of the last glacial slope-fluvial sedimentation cycle [47], thus their chronological collocation is at the end of Late Pleistocene [48]. A characteristic wave-cut scarp parallel to the present shoreline delimits the toe of both the landslide masses and provides suitable exposures of the deposits that here are those typical of rock avalanche/slide phenomena: disrupted rock masses, including rock blocks; chaotic calcareous debris with sandy clay; and a subordinately clay matrix (Figure 3B,C). Rock blocks and calcareous debris belong to the Scaglia Rossa Fm. and subordinately to the Marne a Fucoidi Fm., confirming that both bedrock formations are involved in the mass movement. At the toe of the Portonovo landslide, a deposit belonging to a shallow reactivation of the main landslide body uncomfortably overlays the rock avalanche/slide deposit (Figure 3C). Along the backscatter of both landslides, a series of trenches and ridge-top depressions mark the releasing zone (Figure 3D). A plunging cliff characterizes the southern coastal sector, whose upslope and midslope zones are generally affected by rock-block slides and falls that strongly contribute to the cliff regression (Figure 4). A wide active talus deposit occurs at the footslope, often affected by secondary debris flows and fall phenomena.