TRIASSIC-MIOCENE PALEOGEOGRAPHY AND BASIN EVOLUTION OF THE SUBBETIC ZONE BETWEEN RONDA AND MALAGA, SPAIN

During the Triassic, continental and supratidal environments prevailed in the north of the Ronda-Malaga region whereas intertidal and shallo w marine environments characterize the south. From the Jurassic up to the Miocene, the Ronda-Malaga region was the scene of shallow marine e nvironments in the north and open or deeper marine environments in the south. The Miocene reveals rapidly changing paleo-environments. Durin g the Aquitanian a submarine fan system developed with elastic supply from an emerged area in the north. In the Burdigalian, deformation sta rted to the south of the study area and depositional patterns complete ly reversed, now showing detritus supply from an emerged area in the s outh. The entire area emerged during Langhian and Serravallian times a nd several local extension basins developed in the Tortonian. Backstri pping analysis reveals four phases of accelerated subsidence related t o extension in the Mesozoic: Anisian-Ladinian (241-235Ma), Norian-Hett angian (223-203Ma), Callovian-Tithonian (161-146Ma), and Cenomanian-Tu ronian (97-89Ma). These phases can be correlated with tectonic events in the Central Atlantic Ocean. The Tertiary subsidence record shows a change from slow to rapid subsidence in the Late Oligocene and Early M iocene related to a change from extensional to compressional tectonics . Throughout the Middle and Late Miocene and the Pliocene, strike-slip tectonics resulted in local extension and compression giving rise to renewed basin development. The paleogeographic reconstructions togethe r with subsidence analysis allow to discuss the tectonostratigraphic e volution of the Ronda-Malaga region within the framework of western Me diterranean plate tectonics.