EXPLORATION POTENTIAL IN PLATFORM TO BASIN TRANSITIONAL SETTINGS: EXAMPLES FROM PERI-ADRIATIC TETHYS CARBONATES

Abstract

The area between the platform margin and the distal basin represents a depositional setting where various types of deposits produced and shed by the carbonate platform can accumulate. These deposits can be caused by high-energy catastrophic events related to the tectonic or gravitational collapse of the platform margin or by turbidite currents controlled by carbonate production rates; sea level variations and tectonic activity.

The accumulated sediments can vary from massive megabreccias to turbidites. With their thickness, dimension and distribution strongly controlled by palaeotopography, they can represent prolific, albeit elusive, exploration targets.

During the Mesozoic and the lower Cenozoic the Adriatic region hosted two very extensive carbonate platforms, the Apulian Platform and the Adriatic Platform. Each produced enormous amount of sediments accumulating in the basins separating the two platforms.

These deposits outcrop extensively in Italy, Croatia and Albania and represent excellent analogues for some of the offshore Adriatic discoveries and for some of the plays identified in the basin and that will be targeted by future exploration activity.

This talk demonstrates how the study of carbonate platform margins outcropping in peri-Adriatic areas is of fundamental help in interpreting seismic data for exploration play definition.

For example the distribution and stacking of megabreccias and calcareous turbidites with reservoir potential is often controlled by the structural setting and the fault network existing at the time of deposition. Outcrop analogues are necessary to develop models linking structural to depositional geometries that can be calibrated and applied to subsurface data in order to delineate platform margin plays.

Megabreccias and calcareous turbidites deposited in the platform to basin transition settings of the peri-Adriatic areas represent interesting exploration targets and also analogues for similar plays elsewhere. (Go to www.searchanddiscovery.com to see figures.)

AAPG Datapages/Search and Discovery Article #90226 © 2015 European Regional Conference and Exhibition, Lisbon, Portugal, May 18-19, 2015