Crustal Thickness Beneath the Dinarides and Surrounding Areas From Receiver Functions. Issue 3 (21st March 2020)

• Record Type: Journal Article
• Authors: Stipčević, Josip; Herak, Marijan; Molinari, Irene; Dasović, Iva; Tkalčić, Hrvoje; Gosar, Andrej
• Is Part Of: Tectonics. Volume 39:Issue 3(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-03-21
• Subjects: Mohorovičić discontinuity -- crustal thickness -- Dinarides -- Adriatic microplate -- receiver functions; Geology, Structural -- Periodicals; 551.8
• DOI: 10.1029/2019TC005872
• Languages: English
• ISSNs: 0278-7407

Abstract

Abstract: Knowledge about the crustal thickness is one of the key elements in the reconstruction of the regional tectonic history. The Dinaric mountain belt is one of the most enigmatic segments of the Alpine‐Mediterranean collision zone, characterized by large variations in crustal thickness and not studied sufficiently. We present a new Moho depth map for the wider Dinarides region which was created using teleseismic earthquake recordings from 87 permanent and temporary seismic stations in the region. Teleseismic data were analyzed using the receiver function method to extract converted P to S waves. The resulting Moho topography fits well within a structural framework comprising a thicker crust under the Dinarides, which gradually becomes thinner toward the Pannonian and Adriatic domains. The profiles crossing the northwestern Dinarides are marked by a relatively sharp decrease in crustal thickness north of the main thrust front. This transition is followed by significant crustal thinning toward the Pannonian basin. The Mohorovičić discontinuity lies the deepest in the central and southern Dinarides, at depths of over 55 km. Here similarly to the northwestern segment we observe a jump in the crustal thickness when transitioning toward the Internal Dinarides, which hints at possible underthrusting (or subduction) of the Adria plate in this region. Moho depths in the transition zone toward the Pannonian basin and in the Pannonian basin proper vary between 25 and 35 km. In the Adriatic domain, we find crustal thickness ranging from 30 km to more than 45 km around the Central Adriatic islands. Key Points: New crustal thickness map of the Dinarides and surrounding areas Thicker crust in the central Adriatic, a deep crustal root in the south Dinarides and a tightly constrained transition from the deep Dinaric to the shallower Pannonian Moho Jump in the crustal thickness when transitioning toward the Internal Dinarides, which hints at possible underthrusting of the Adria plate in this region