Resumen de Oolitos ferruginosos en el Mioceno inferior-medio de Mallorca: posición estratigráfica y significado paleogeográfico
Emilio Ramos Guerrero, B. Segovia
The syn-orogenic early-middle Miocene of Mallorca constitutes a sequence which records the deepening and intill ot small foredeeps related to flexural subsidence caused by the Betic orogene thrusting. In the syn-orogenic Miocene of the central part of the island', an oolitic iron bed (< 20 cm thick) is first described in order to consider their stratigraphic, environm ental and palaeogeographic significance. The oolites are highly spherical and range from less than 0.25 to more than 6 mm in size. They are formed by concentric thin laminae (< 10 pm) of goethite, but traces of greenalite have been noted. The largest-sized oolites also contain calcite laminae. The oolitic bed can be correlated with the maximum flooding surface, and records the maximum aieal extent ot the marine platform. After this deposit, deeper turbiditic sedimentation is recorded in the basin. The Burdigalian volcanism described in the zone is invoked as the iron source.
