Ключевые слова: abstract, apennines, background, close, delicate, emilia, erode, erosion, europe, geological, geology, grass, grey, irregular, italia, italy, limestone, mineral, mountain, nature, piacenza, profile, rock, romagna, sandstone, shade, shadow, silhouette, smooth, stone, surface, texture, trebbia, up, val, valley, valtrebbia, wallpaper,