The problem of the absence of allochthonous units (Ligurides s.I.), which characterizes the Romagna Apennines, was faced with three main methodological approaches: estimation of illite crystallinity in the Marnoso-Arenacea Formation; structural analysis of the upper Messinian post-evaporitic conglomerates and of the clastic "intrapenninic" Pliocene deposits; study of the composition of ruditic deposits belonging to the depositional sequence of the Apenninic border, whose clasts come from the Ligurian units and the Epiligurian Sequence. The preliminary results of these studies seem to indicate that the Mamoso-Arenacea Formation was overthrusted by the Ligurian allochthonous units. The following erosion should have taken piace mainly during the uplift of Pleistocene age, corresponding the enormous volumes of clastic deposits in the sequence of the Apenninic border. The geometric-kinematic relationships between thrusts displacing the MamosoArenacea Formation and residual allochthonous sheets (Marecchia Valley, "Sillaro Structural System") suggest a duplex structure for the entire belt sector.
L'assenza delle Liguridi nell'Appennino Romagnolo: Relazioni con il sollevamento quaternario e implicazioni strutturali
SARTI, GIOVANNI
1997-01-01
Abstract
The problem of the absence of allochthonous units (Ligurides s.I.), which characterizes the Romagna Apennines, was faced with three main methodological approaches: estimation of illite crystallinity in the Marnoso-Arenacea Formation; structural analysis of the upper Messinian post-evaporitic conglomerates and of the clastic "intrapenninic" Pliocene deposits; study of the composition of ruditic deposits belonging to the depositional sequence of the Apenninic border, whose clasts come from the Ligurian units and the Epiligurian Sequence. The preliminary results of these studies seem to indicate that the Mamoso-Arenacea Formation was overthrusted by the Ligurian allochthonous units. The following erosion should have taken piace mainly during the uplift of Pleistocene age, corresponding the enormous volumes of clastic deposits in the sequence of the Apenninic border. The geometric-kinematic relationships between thrusts displacing the MamosoArenacea Formation and residual allochthonous sheets (Marecchia Valley, "Sillaro Structural System") suggest a duplex structure for the entire belt sector.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
