 The eastern coast's largest part consists of carbonate rocks, while flysch rock is significantly represented in the Gulf of Trieste coast, on the Kvarner Gulf coast opposite Krk, and in Dalmatia north of Split.There are comparably small alluvial areas of the Adriatic coast in Croatia—most notably the Neretva river delta.Western Istria is gradually subsiding, having sunk about in the past 2,000 years.