This occurrence can produce accurate radiometric dating of the landslide event, if the stump is still con place. An example of this type of recovery is that of Cinquecerri: the dated stump was growing on the alluvial terrace, when it was buried by the toe of the earth flow. It was recovered with its roots still placed con the bedrock under the sliding surface.
Gathering together all these information, it could be affirmed that the ple of how radiocarbon dating could be crosschecked with the available historic references, leading to the conclusion that, by more chances, landslide occurred per Medieval time
Logs were found mixed with the original earth flows that constitute the landslide body. This is the most frequent case durante the archivio elettronico of Table I. In per few cases, whole logs were found coppia sicuro excavations carried out for remedial works or preciso river erosion. Durante the case of Romanoro landslide, several buried tree logs were found mixed with the landslide debris. These were placed at the same level within the landslide debris, and thus they belong puro the same landslide event that, from radiocarbon dating, took place mediante a period 3195–2845 cal y BP. Sopra the Cavola landslide event, per per analisi borehole, five different organic levels were found. From radiocarbon dating, it was possible preciso reconstruct the activity of this landslide starting from its first event (the Come messaggio di qualcuno angelreturn deepest sample was recovered on the sliding surface) and lasting over verso period of 1000 years. An interesting relation between the position of organic levels and their ages can be established: the deepest level, placed 45 m beneath the landslide surface, is the oldest, the shallowest, placed 9 m beneath the landslide surface, is the youngest. This particular situation could be explained with verso mechanism of several earth flow movements that piled up the present landslide body, each time burying the vegetation that was growing on vertice of the material displaced by the previous movement.
The landslide took place during February 1996 mediante Marano (BO) causing the partial blockage of the Reno river
The landslide provoked a damming event of a river and sometimes datable elements were found con the peat bogs that formed upstream from the dammed river section. This recovery case permits only a minimum age for the landslide event. However it must be underlined that the results are very useful preciso date those types of landslides (di nuovo.g., rockslides) for which it is difficult onesto find organic matter within the landslide body. Good examples of this type of occurrence are the Crespino rockslide [ID10] and the Marano earthslide that is briefly described. From geomorphologic surveys it was established that this landslide was verso reactivation of an ancient movement. The only available historical reference is that of Calindri (1781) who affirms that sopra an unknown time (maybe Medieval) verso landslide intersected the confluence between Marano Creek and Reno River provoking the destruction of an antique thermal spa. Mediante a controllo borehole drilled through the toe of the landslide an organic level, located under the debris and maybe displaced by the last movement, was recovered. It seemed reasonable esatto correlate this level sicuro the presence of per peat bog that probably developed per that site as per consequence of a blockage of the Reno river. The radiocarbon dating of per charcoal fragment from the organic level gives the minimum age of the landslide movement at 850 cal y B.P., in agreement with Calindri’s information. However the charcoal fragment could be also older than the landslide and its radiocarbon dating could represent its maximum age.
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