Plate 103

Association of tool and fluid-made marks

Another case of bed turned upside down, this time in a Cretaceous flysch (Monghidoro Formation, northern Apennines), displays finely chiseled basal markings. Subdued flute casts are associated with a variety of shallow scratches (groove, striation and impact casts). In addition, they are overprinted by short, sinuous, keeled marks made by organisms (trace fossils: see plates 156, 157). The paleocurrent direction is determinable. Can you do it?