Abstract: Sequence Stratigraphy in Active Tectonic Setting--Plio-Pleistocene of Tyrrhenian Sea and Sicily--Comparison With The Gulf Of Mexico

R. Catalano, E. Di Stefano, S. Infuso, A. Sulli, P. R. Vail, F. P. Vitale

A chronostratigraphic framework of the Plio-Pleistocene on and offshore Sicily has been constructed using the sequence stratigraphy interpretative processes and tools. The study analyzed a number of outcropping reference succession on land using facies analysis, high resolution calcareous plankton integrated biostratigraphy and magnetostratigraphy. Physical and biochronological correlations of buried succession in the Tyrrhenian Sea and Sicily Channel have also been provided using well-log pattern analysis and seismic stratigraphy analysis. The main transgressive-regressive facies cycles are pointed out, among which are developed ten third order depositional sequences and their systems tracts in the interval 4.8-0.8 My, and eight minor order sequences reflecting the high-frequency sea level fluctuations occurred between 0.8 My and the Holocene.

One of the most important aspect investigated is the interplay between the tectonic influences and the eustatic oscillations on the basin fills: we demonstrate that the studied successions are characterized by very similar stratal geometries both in the tectonically active and passive margins. Moreover, our data indicate as substantially sinchronous the sequence boundaries ages all over the area, and striking similarities with the Plio-Pleistocene chronostratigraphic chart of the Gulf of Mexico (Wornardt and Vail, 1991). A common stratigraphic signature is evidentiated in the mainland and both northern and southern margins successions: thrusting and transgression until 3.0 My,

regression and synsedimentary extensional tectonics between 3.0 and 2.4 My, compression and regression to 1.2 My, transgression and regional subsidence to 0.8 My, compression and regression to 0.5 My, subsidence coupled with strong vertical tectonics from 0.5 to Holocene. These widespread regional character in the record suggests an eustatic origin for the main unconformities, as well as stratal pattern accommodations and subsidence variations in response to the main tectonic events and related structures growth.

AAPG Search and Discovery Article #90986©1994 AAPG Annual Convention, Denver, Colorado, June 12-15, 1994