Alpine plate kinematics revisited: The adria problem

Abstract

Tectonic evolution of the Alpine Tethys is controlled by the plate movements of Africa, Europe, and the Adriatic microplate. It is, however, unclear to which extent and at what times the motion of Adria was related to Africa. Kinematic models which assume a rigid connection between Africa and Adria have difficulties in explaining the Alpine rock record. Reconstructions based on the Alpine record are, on the other hand, in conflict with the involved kinematics. To resolve these conflicts, they require complicated motions or the introduction of additional microplates. Here we present a solution which is based on a rigid connection between Africa/Adria during Jurassic/Cretaceous times. Our model requires only four plates, involving Africa, Europe, Iberia, and Adria. It describes a self-consistent kinematic evolution of the western Tethyan microplate motions from Jurassic to Miocene times. The initial (Early Jurassic) plate configuration was found by iterative forward modeling. The resulting Jurassic plate configuration is unusual and provides new insights into Alpine geology. The obtained model is, however, in good agreement with the available geological data and suggests that the assumption of independent movements of Adria during Jurassic/Cretaceous times is not a necessity.