Palaeomagnetism of Cretaceous carbonates from the northwestern part of the Dinaric fold belt

From the island of Cres and the fold belt north of autochthonous Istria 260 light-grey Cretaceous limestone samples were collected at 25 localities. Stepwise thermal demagnetization was employed to clean the remanence up to max. 525 °C. About two-thirds of the samples were successfully cleaned and the locality means were calculated from the characteristic remanences. The locality means significantly deviate from the present field direction both before and after tectonic correction: the mean inclination is about 15° lower than the present inclination and the declination is rotated counterclockwise i.e. it basically fits the pattern so far observed in the Periadriatic region.Unfolding barely influences the scatter of the directions (Cres: D = 308°, I = 45°, k = 26, α₉₅ = 13.3°, before tilt correction, and D = 330°, I = 48°, k = 33, α₉₅ = 11.9° after tilt correction; fold belt north of autochthonous Istria: D = 309°, I = 48°, k = 17, α₉₅ = 11.9°, before tilt correction, and D = 336°, I = 41°, k =13, α₉₅ = 14.0°, after tilt correction. In view of the inconclusive fold test, the magnetization cannot be dated precisely and thus does not yield sufficient information concerning possible relative movements between autochthonous Istria-Gargano and the fold belt studied. Nevertheless, the counterclockwise rotated declinations of the area studied are in contrast with the clockwise rotated declinations of the Ionian Zone of Western Greece. The large angular difference in declination between two parts of the Dalmatian-Ionian Zone with similar tectonic trends casts doubt on the continuity of the fold belt.