engleski

New insights into the tectonic history of the external dinarides based on mesozoic paleomagnetic results

Adria is a crustal block of African origin, playing an important role in the geodynamic history of the Central Mediterranean s.l. It comprises a gently deformed „autochthonous” core and thrusted and folded margins, including the External Dinarides. As a result of systematic paleomagnetic research, a well- defined Jurassic–Eocene APW is now available for the core, based on direct data, which is moderately, but systematically displaced from the APWs transferred to stable Adria from outside. This APW can serve as a paleomagnetic reference frame from describing possible relative movements between the core and the deformed margins. In this presentation we shall discuss the situation in the External Dinarides, using Jurassic and Cretaceous paleomagnetic results from the Northern and Central Adriatic islands and the Velebit and Gorski kotar area on the mainland. Our results from stable Adria as well as from the External Dinarides were obtained from biostratigraphically precisely dated (often to a stage) sediments and the age of the magnetization constrained by positive tilt test or at least improving scatter (mostly subhorizontal strata) on tilt corrections. Moreover, each of the studied areas is represented by paleomagnetic directions of different ages, enhancing the reliability of the main tectonic conclusions, which are the followings. Stable Adria and what is called imbricated NE margin (comprising all of the studied Adriatic islands) should be considered as an entity, with no large scale relative movements between its different parts. The Velebit Mts and Gorski Kotar belong to an other tectonic superunit, which was either an independent carbonate platform during the Mesozoic or changed orientation with respect to stable Adria during overthrusting imbricated Adria.

External Dinarides; Mesozoic; paleomagnetic results; tectonic application

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