New data on Structural Relationships in the North Dalmatian Dinaride Area

Abstract

Subsurface structural relationships are presented based on gravity data and seismic reflection profiles. Reflection marker horizons and the relative positions of different rock masses and structural units have been established, and are compared with surface observations. Active zones, marked by pronounced reflection boundaries in seismic profiles, have been established, the deepest of which are connected with the Dugi Otok fault zone. Below this interface, rock masses of the Adriatic platform underthrust the Dinarides. The active underthrusting plane reaches a depth of about 17 km. In the northern part of the area under consideration, contours of upthrown rock masses at depths of 5 to 11 km have been established. The area of numerous reverse faults is particularly active, and is defined on the surface by the Obrovac-Drnis-Klis fault. Reconstruction of tectonic movements indicates that rotation of structures and dextral strike slips have occurred, particularly along this fault zone.