Apparent polar wander path for Adria extended by new Jurassic paleomagnetic results from its stable core: Tectonic implications

• Published in: Tectonophysics 2017-03, Vol.700-701, p.1-18
• Main Authors: Márton, Emő, Zampieri, Dario, Ćosović, Vlasta, Moro, Alan, Drobne, Katica
• Format: Article
• Language: English
• Subjects: 167–41 Ma apparent polar wander; Carbonates; Cretaceous; Eocene; Geographical distribution; Geological time; Jurassic; Kinematics; Magnetic fields; Plate tectonics; Rotation; Shallow water; Stable Adria; Studies; Tectonic implications
• ISSN: 0040-1951; 1879-3266
• DOI: 10.1016/j.tecto.2017.02.004

As a continuation of a systematic paleomagnetic research in the northern part of stable Adria, which provided a well-defined apparent polar wander (APW) path for the Cretaceous-Eocene, we present new paleomagnetic results for the Jurassic. These new data were obtained from 15 geographically distributed localities from the Trento platform (eastern Southern Alps) using standard paleomagnetic approach. The Lower Jurassic shallow water carbonates are not considered for tectonic interpretation, due to inconsistent inclinations. The Middle and Upper Jurassic Rosso Ammonitico provided excellent kinematic constraints. With the new Jurassic results, an APW is now defined for Adria for the 167–40Ma interval. It is well constrained for timing of important changes, like the speed and the sense of rotations. This APW suggests that the CW rotation and southward shift changed to the opposite at 155.1±5.3Ma, signifying a dramatic change in the life of the Neo-Tethys, from opening to closing. The latter is manifested in fast CCW rotation and northward movement of Adria up to 102.9±2.4Ma and moderate displacements in the same manner in post-103Ma times. Combined data sets from stable Istria and the foreland of the Southern Alps point to an approximately 15° CW rotation with respect to Africa at the end of the Cretaceous, and an about 25° in the CCW sense, after the Eocene. •The new 167–41Ma APW for stable Adria is based on data from its northern parts.•The APW exhibits a hairpin between 167 and 103Ma, with a turning point at 153Ma.•The hairpin is due to shift to S/N and CW/CCW rotation of Adria before/after 153Ma.•The above movements are related to the opening/initial closing of the Neo-Tethys.•Adria rotated relative to Africa 15°CW around 80Ma, and 30 CCW after the Eocene.