Tectonic activity in the Croatian part of the Pannonian basin

Identification of tectonically active areas using DEM: a quantitative morphometric analysis of Mt. Medvednica, NW Croatia

“…How ever, those ar eas can not be rea son ably as sumed as tec toni cally ac tive be cause lo cal re lief, hypsometry and lon gi tu di nal stream pro file anal y sis point to streams char ac ter ized by low lo cal re lief val ues, concave hypsometric curves (H i < 0.40), and lon gi tu di nal pro file pa ram e ters, con firm ing stream equi lib rium con di tions, re spectively (Ta ble 1). The iden ti fied on go ing tec tonic up lift within de lin eated ar eas also cor re lates well with mod er ate pres ent-day seis mic ity with rare oc cur rences of strong earth quakes (M L > 5) within ma jor seismogenic sources in the Medvednica-Zagreb epicentral area (e.g., Prelogoviae et al, 1998;Herak et al, 2009 with ref erences). The first de lin eated tec toni cally ac tive area (along side the SW cor ner of NW moun tain front) co in cides with the southwest ern seg ment of the NMBF, a steeply SSE-dip ping re verse fault zone, while the lat ter area (nar row bound ary zone di vid ing Mt.…”

“…Medvednica in com bi na tion with prom i nent ba sin asym metries and abrupt changes in asym me try di rec tions sense were rec og nized in a nar row bound ary zone as so ci ated with the NW-strik ing Kašina Fault zone. Al though the NW-strik ing Kašina Fault zone was in ter preted by pre vi ous stud ies (e.g., Prelogoviae et al, 1998;Tomljenoviae and Csontos, 2001;Tomljenoviae et al, 2008) as a right-lat eral strike-slip fault, our study sug gests that con sid er able lo cal re lief dif fer ences are prob a bly a re sult of ad di tional Kašina Fault nor mal move ment. Tec tonic up lift in this zone is also sup ported by hypsometry data; how ever, with lon gi tu di nal stream pro file anal y sis (C f , C max.…”

“…The fi nal stage in the for ma tion of these folds, which com menced dur ing the lat est Mio cene (ca. 6 Ma) un der a N-S to NW-SE di rected short en ing, is well-doc umented by out crop struc tural anal y ses and seis mic re flec tion data (e.g., Fodor et al, 1998;Gosar, 1998;Prelogoviae et al, 1998;Vrabec, 1999;Tomljenoviae and Csontos, 2001). In ad dition to fold ing, the short en ing was ac com mo dated by per va sive brit tle de for ma tion and the for ma tion of E-W-strik ing re verse faults.…”

“…Geo log i cally, this nar row bound ary zone cor re sponds to the NW-strik ing Kašina Fault zone (Fig. 4B), which is in ter preted as a right-lat eral strike-slip fault by pre vi ous stud ies (e.g., Prelogoviae et al, 1998;Tomljenoviae and Csontos, 2001;Tomljenoviae et al, 2008). How ever, the sig nif i cant lo cal re lief dif fer ences within the two fault sides sug gest that, in ad di tion to the pro posed right-lat eral strike-slip com po nent, this fault zone ac com mo dated a prom i nent nor mal dis place ment.…”

“…Medvednica drain age bas ins that we then com pared to sepa rate those rep re sent ing tec toni cally ac tive vs. in ac tive sub-areas. These new data were then com pared with the re sults from pre vi ous geomorphologic, neotectonic and seismotectonic stud ies of this area (Heaeimoviae, 1984(Heaeimoviae, , 2000Prelogoviae et al, 1998;Tomljenoviae and Csontos, 2001;Tomljenoviae et al, 2008;Herak et al, 2009). …”