Identification of Future Earthquake Sources in the Carpatho-Balkan Orogenic Belt Using Morphostructural Criteria

Abstract

—The Carpatho-Balkan mountain belt, the most seismic zone of the Circum-Pannonian region, is studied with a goal to identify sites where shallow earthquakes with M≥ 6.5 may occur. The study is based on the assumption that strong earthquakes associate with disjunctive nodes that are formed around the junctions of lineaments. In the study region, lineaments and disjunctive nodes were defined by a morphostructural zonation method. The morphostructural map compiled at the scale of 1:1,000,000 shows a hierarchical system of homogeneous blocks, the network of morphostructural lineaments and the loci of disjunctive nodes. Shallow earthquakes with M _s ≥ 5.0 recorded in the region were found to be nucleated at the mapped nodes. In the Carpatho-Balkan mountain belt, the nodes where earthquakes with M≥ 6.5 may occur have been identified using morphostructural criteria of high seismicity, previously derived from pattern-recognition of potential seismic nodes in the Pamirs-Tien Shan region. In total, 64 of the 165 nodes mapped in the studied region have been defined to be prone to earthquakes of M≥ 6.5. These 64 nodes include the seven where earthquakes of M _s ≥ 6.0 already took place.