A south Adriatic shelf offshore the prevalently carbonate Apulian coast is characterized by a peculiar rough topography interpreted as relic karst formed at time of lowered sea level. The study area covers a surface of ca. 220 km2 in a depth range of 50- 105 m. The most relevant and diagnostic feature is represented by circular depressions a few tens to 150 m in diameter and 0.50 to 20 m deep thought to be dolinas at various stages of evolution. The major dolina (Oyster pit) has its top at ca. 50 m water depth and is 20 m deep. Its crater is partly filled by episodic mass failure from the dolina's flanks remobilizing Pleistocene pebbly-shelly sediments. Bedrock samples from the study area document that Plio-Pleistocene calcarenites (tentatively correlated with Calcarenite di Gravina Fm.) are a prime candidate of carbonate rocks involved in karstification, although the presence of other units (Peschici and/or Maiolica Fms) is not discarded. The area containing this subaerial karst landscape was submerged ca. 12500 years ago as a result of the postglacial transgression over the continental shelf.
Drowned karst landscape offshore the Apulian Margin (Southern Adriatic Sea, Italy)
MORSILLI, Michele;
2012
Abstract
A south Adriatic shelf offshore the prevalently carbonate Apulian coast is characterized by a peculiar rough topography interpreted as relic karst formed at time of lowered sea level. The study area covers a surface of ca. 220 km2 in a depth range of 50- 105 m. The most relevant and diagnostic feature is represented by circular depressions a few tens to 150 m in diameter and 0.50 to 20 m deep thought to be dolinas at various stages of evolution. The major dolina (Oyster pit) has its top at ca. 50 m water depth and is 20 m deep. Its crater is partly filled by episodic mass failure from the dolina's flanks remobilizing Pleistocene pebbly-shelly sediments. Bedrock samples from the study area document that Plio-Pleistocene calcarenites (tentatively correlated with Calcarenite di Gravina Fm.) are a prime candidate of carbonate rocks involved in karstification, although the presence of other units (Peschici and/or Maiolica Fms) is not discarded. The area containing this subaerial karst landscape was submerged ca. 12500 years ago as a result of the postglacial transgression over the continental shelf.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
