Palaeontological and sedimentologic criteria for high resolution environmental analysis: the Pleistocene succession at Torre Ovo (Salento, south italy)

Abstract

D’Alessandro A. & Loiacono F., Palaeontological and sedimentologic criteria for high resolution environmental analysis:
The Pleistocene succession at Torre Ovo (Salento, South Italy). (IT ISSN 0394-3356, 2010).
The about 15 m thick middle and upper Pleistocene succession outcropping near Torre Ovo (south of Taranto, Salento), contains
diverse assemblages of body and trace fossils. The assemblages are sensitive indicator of environmental parameters and allow to
recognize stratigraphic key surfaces and infer sedimentation dynamics. The lower unit (1) is a marine faintly layered muddy fine sand,
that may be attributable to the middle Pleistocene. The following unit (2) is a marine calcarenite, possibly deposited during M.I.S. 5.5.
Blocks of algal calcarenite included in the basal transgressive lag are reworked from inferred M.I.S.7 deposits. The succession ends
with a continental unit subdivided into sub-units 3A and 3B, which are late Pleistocene or Holocene in age. Unit (1) includes rare trace
fossils in paramoudra-preservation. During a phase of subaerial exposure in a hot, semi-arid climate, the deposit was subjected to
intense vadose diagenesis. Unit (2) can be subdivided into four sub-units: 2A and 2B represent the trangressive systems tract, 2C
records the condensed maximum flooding zone, and 2D the regressive systems tract. Greyish calcarenite (3A), laps onto the basal
part of unit 2. Its upper part includes pebbles and blocks of sub-unit 2D. The sediment is pervasively bioturbated (Camborygma
shafts). This ichnogenus is indicative of a terrestrial environment, firm substrate and is influenced by the ground water level. Sub-unit
3B, partly coeval to sub-unit 3A, is a reddish terrigenous conglomerate including few Camborygma shafts in rare sand lenses.
Tentatively, the deposit has been attributed to M.I.S 3.