I’m a specialist of vertebrate tracks. During a long stay at Kinshasa, I discovered a number of tracks of early mammals, on slabs of purple sandstone. The tracks are of bad quality; however, they are interesting: they would be the first vertebrate tracks in Congo, and they are very similar to Brasilichnium elusivum and similar tracks, from Botucatu Formation and Caiuá Group, LK, in Brazil. Those sandstones are very common at Kinshasa, also on the sidewalks. They came from natural outcrops and quarries inside W outskirts of the town of Kinshasa, on the banks of Congo river, in the quarters of Kinsuka, Mbudi, Pompage. I could not find in situ or in internet any detailed Geological map of the Phanerozoic of Congo and of Kinshasa. To publish these tracks, I need the name and if possible the dating of this formation. Can any colleague help me? Thank you. Giuseppe Leonardi
Dear Dr. Leonardi,
even if you could only provide us with a limited insight into the surface phenonmena of these sandstones I would discard the idea of being biogenic in origin and I would rather attribute this kind of sandstone structures to what might be called sensu lato as parting (lineation). It is not uncommon at outcrop and when used as glading it shows this man-made way of exfoliation. You might find these structures in some otherwise monotonous arenaceous series such as those created by turbidite currents.
With kind regards
H.G.Dill
Dear Dr. Dill,
thank you very much for you kindness and competent answer. Yes, really, I could shaw very little of my material. Very kindly and thankfully, I’ll say that I’ve seen and studied a lot of sandstones; and I know parting lineation. However, the roundish cavities, accompanied by a crescent convexity from those slabs from Kinshasa, are very similar (although they are bad quality) to footprints and sure trackways from the Cretaceous of Brazil. Here I join two examples of trackways Brasilichnium elusivum Leonardi, 1981, from Brazilian LK, on very similar kind of sandstone.
All the very best. Giuseppe