Con trast ing tec tonic styles of the west ern and east ern parts of the West ern Carpathian Klippen Belt in Slovakia based
on magnetotelluric sound ing of deep tec tonic struc tures
Vladimír BEZÁK1, *, Ján VOZÁR1, Dušan MAJCIN1, Radek KLANICA2 and Ján MADARÁS1
1 Slo vak Acad emy of Sci ences, Earth Sci ence In sti tute, Dúbravská 9, 840 05 Bratislava, Slo vak Re pub lic
2 In sti tute of Geo phys ics of the Czech Acad emy of Sci ences, Boèní II/1401, 141 31 Praha 4, Czech Re pub lic
Bezák, V., Vozár, J., Majcin, D., Klanica, R., Madarás, J., 2021. Con trast ing tec tonic styles of the west ern and east ern parts of the West ern Carpathian Klippen Belt in Slovakia based on magnetotelluric sound ing of deep tec tonic struc tures. Geo log i - cal Quar terly, 2021, 65: 25, doi: 10.7306/gq.1595
To char ac ter ize the deep struc ture of the Klippen Belt, we made magnetotelluric mea sure ments in pro files across the west - ern and east ern seg ments in the ter ri tory of Slovakia, from which we cre ated 3D mod els. The mod els re vealed sig nif i cant dif fer ences in tec tonic struc ture be tween these seg ments. In the west ern seg ment, the Klippen Belt is lo cated in the south ern re vers ing wing of the orig i nal subduction flower struc ture (retroarc thrust ing) with an overthrust to the south onto the In ner West ern Carpathian units. This struc ture was later mod i fied by sig nif i cant transpressional move ments. In the east ern seg - ment, the Klippen Belt is pri mar ily an or ganic part of the accretionary wedge of the Outer West ern Carpathians and it is overthrusted onto the Flysch Belt. This was fol lowed by mod i fi ca tion of the struc tures, mostly in a transpressional re gime, in - clud ing lo cal re vers ing overthrusts and the de vel op ment of a steep fault bound ary, mainly along the south ern mar gin, against the In ner Carpathian Paleogene suc ces sion. These dif fer ences be tween the struc ture of the west ern and east ern Klippen Belt seg ments in di cate the con trast be tween the in ter ac tion of the west ern and east ern parts of the In ner West ern Carpathians with the Eu ro pean Plat form. In the west ern part, oblique col li sion and sinistral transpression dom i nate. In the east ern part, by con trast, subduction and or thogo nal col li sion dom i nated over later transpressional mod i fi ca tions.
Key words: West ern Carpathians, Klippen Belt, magnetotelluric sound ing, deep struc tures, subduction, col li sion, transpression.
INTRODUCTION
The tec tonic style of the in ter ac tion of the In ner West ern Carpathian (IWC) Block with the Eu ro pean Plat form (EP) has been de scribed in many stud ies con cern ing the de vel op ment of the en tire Al pine-Carpathian-Pannonian re gion dur ing the Mio - cene. Re search into the de vel op ment of the Klippen Belt (KB) can play an im por tant role in un der stand ing this re gion. We use the more gen eral term “Klippen Belt” fol low ing the ter mi nol ogy of the Tec tonic Map of Slovakia (Bezák et al., 2004), and with re gard to its var i ous named sec tions (e.g., Kysuca, Orava, Pieniny, Šariš seg ments). This seems ap pro pri ate, al though in the lit er a ture the term Pieniny Klippen Belt is more com monly used. The KB lies on the bor der of the Outer West ern Carpathians (OWC) and IWC and thus its deeper struc ture may re flect the char ac ter of IWC/OWC con tact.
The lat eral ex tru sion pro cess of the Carpathian -Panno nian ter ranes from the area of the East ern Alps un der pres sure from the Adria microcontinent into the area of the North Penninic flysch ba sin has been de scribed in sev eral stud ies (e.g., Ratsch ba cher et al., 1991; Beidinger and Decker, 2016).
Other stud ies have looked into the Neo gene evo lu tion of the Carpathian -Pannonian re gion where subduction of oce anic crust cov ered by flysch de pos its was fol lowed by col li sion and the for ma tion of Neo gene bas ins as so ci ated with vol ca nic ac - tiv ity (Royden et al., 1982; Csontos et al., 1992; Nemèok et al., 1998; Lexa and Koneèný, 1998; Fodor et al., 1999). Most of the stud ies have con cluded that, in the case of the West ern Carpathians, oblique col li sion of the IWC Block with the EP oc - curred, ac com pa nied by sinistral transpression (e.g., Sperner et al., 2002).
The po si tion of KB at the bor der of the IWC and OWC has al - ways been sub ject to de bate. KB com plexes, as rem nants of the Mesoalpine orogen, be came part of the IWC Block to gether with Palaeoalpine units, and were lo cated in the IWC fore land. At the Neoalpine stage of tec tonic evo lu tion, they par tic i pated in the de - vel op ment of an accretionary OWC wedge, and later they be - came part of the transpressional zone. The transpressional move ments led to refolding of the KB units, the cre ation of flower struc tures, and backthrusting as so ci ated with strike-slip move -
* Corresponding author, e-mail: geofbezv@savba.sk Received: December 16, 2020; accepted: April 1, 2021; first published online: May 26, 2021
ments (e.g., Ratschbacher et al., 1993; Jurewicz, 1997; Pešková et al., 2009; Ludwiniak, 2018) and/or ear lier sub duction (e.g., Birkenmajer, 1986). There fore, dur ing the geo log i cal map ping of the KB zone, all struc tures (the north-vergent overthrust, transpressional, and backthrusts) were iden ti fied. All these struc - tures were a con se quence of a com pli cated tec tonic de vel op - ment, and each struc ture re flected one of its stages.
The KB zone is rel a tively very well ex plored. The re con - struc tions of the tec tonic de vel op ment of the KB were based mostly on sur face map ping (the re gion we stud ied is cov ered mainly by the geo log i cal maps of Haško and Polák, 1978;
Nemèok, 1990; Gross et al., 1994; Janoèko et al., 2000; and Teïák et al., 2016) with sup port ing struc tural and strati graphi cal re cords and rare bore holes. Based on these works, fur ther con - cepts of the tec tonic de vel op ment of the KB in its sep a rate sec - tions were pub lished (e.g., Kováè and Hók, 1996; Krobicki et al., 2003; Oszczypko and Oszczypko-Clowes, 2014; Jurewicz, 2018). The struc tural mea sure ments in di cated also dif fer ences be tween the tec tonic de vel op ment of the west ern and east ern seg ments (Plašienka et al., 2019). Our goal was to use geo - phys i cal meth ods to ex am ine KB’s po si tion at deeper lev els (3–5 km), com par ing KB struc tures at this deeper level with ex - ist ing con cepts of its de vel op ment. MT emerged as the most suit able method for this study since the res o lu tion of gravimetry is less sen si tive to li thol ogy and seis mic anal y sis is less sen si - tive to steep struc tures and to lithological vari a tion. MT, by con - trast, was sen si tive to the lithological prop er ties of the rock bod - ies we stud ied. There fore, we im ple mented MT sound ing in
three pro files across the KB in its west ern and east ern seg - ments (Figs. 1 and 2) to ex am ine the deeper struc tures along the con tact zone be tween the IWC Block and EP. We also used the newly mod elled MT-4 sec tion in the east ern part of KB (Majcin et al., 2018). The area that lies be tween our pro files, sum ma rized in the work of Golonka et al. (2005), is a rich source of in for ma tion, es pe cially re gard ing bore holes and MT pro files. For com par i son, we also used seis mic, gravimetric and mag netic data (Vozár and Šantavý, 1999; Janik et al., 2009;
Hrubcová et al., 2010; Bielik et al., 2010; Grabowska et al., 2011; Kuchariè et al., 2013) and mainly MT mod els from west - ern Slovakia (Kováèiková et al., 2005; Bezák et al., 2014), east - ern Slovakia (Ry³ko and Tomaœ, 2005) and Ukraine (Kováèi - ková et al., 2019).
This work is a con tri bu tion to the long-term re search of KB, a geo log i cal phe nom e non which since the 19th cen tury has en - gaged gen er a tions of ex cel lent ge ol o gists. We ob tained a closer view of the deeper struc tures of KB and neigh bour ing units based on the MT sur vey, and use the new geoelectrical MT im age to dis cuss the struc tural de vel op ment pro cesses and their causes .
GEOLOGICAL SETTING
The ge ol ogy of the West ern Carpathians (WCp) is well-doc - u mented in re cent syn thetic maps (e.g., Lexa et al., 2000;
2 Vladimír Bezák et al. / Geological Quarterly, 2021, 65: 25
Fig. 1. Lo ca tion of the area stud ied (red poly gon) in the north ern part of the Carpathian-Pannonian re gion, with gen er al ized tec tonic map mod i fied af ter Majcin et al. (2018)
Bezák, 2008) and in many other pub li ca tions. It has been re - cently sum ma rized in the stud ies of Biely (1989), Plašienka et al. (1997), Froitzheim et al. (2008), Bezák et al. (2011) and Plašienka (2018). In this study, we fo cus mainly on those el e - ments of ge ol ogy which have a di rect re la tion to the is sue ad - dressed by this manu script.
Re cent maps (e.g., Lexa et al., 2000) doc u ment the mor - phol ogy of WCp as an arc moun tain range, the na ture of which is de lim ited by the OWC Flysch Belt (FB). It is an accretionary prism com pris ing flysch strata pushed up from the ocean ba sin on the south ern bor der of EP by the pres sure of the ad vanc ing IWC blocks, which grad u ally filled this ba sin area, with even tual col li sion that gave the whole moun tain range its fi nal shape.
The IWC Block (up per plate in the col li sion) is formed by the Palaeoalpine (Cre ta ceous) crustal and su per fi cial nappes and post-nappe Ce no zoic sed i men tary and vol ca nic for ma tions.
The crustal nappes are formed of the Hercynian crys tal line base ment and its Up per Pa leo zoic and Me so zoic cover, and the su per fi cial nappes only of Up per Pa leo zoic and Me so zoic se quences (e.g., Plašienka et al., 1997). The crys tal line base - ment con tains sev eral Hercynian tec tonic units com posed of meta mor phic com plexes and granitoids (Bezák et al., 1997).
Dur ing the suc ceed ing Mesoalpine col li sion, the IWC units also ab sorbed the KB units (sed i men tary de pos its and their crys tal - line base ment), these be ing the re sult of clo sure of the South Penninic Oce anic Ba sin in the for mer IWC fore land.
The IWC Block formed in these pre vi ous pro cesses, to - gether with other (Pannonian) ter ranes (Pelsonia, Tisia, Dacia),
was pushed into the North Penninic oce anic area dur ing the Neoalpine subduction of this ba sin, and grad u ally col lided with the EP.
The fol low ing ba sic tec tonic units are parts of the geo log i cal struc tures in the area stud ied (Fig. 2): from the north, there is the FB as an ac cre tion prism OWC thrusted onto the EP, the KB zone at the front of IWC units and then other Palaeoalpine units of Tatricum, Fatricum and Hronicum in the Malá Fatra Mts., Choèské vrchy Mts., Tatry Mts. and the “Ružbašský ostrov”.
Transgressive ICP de pos its lie on these Palaeoalpine-formed units. To day they are pre served within grabens, sep a rated by Neoalpine faults from the moun tains. The most sig nif i cant faults in this area in clude the Prosiek, Tatry, Vikartovce, Ružbachy and Branisko faults, and faults lin ing the KB. ICP units also ap pear sep a rately in moun tains such as the Levoèské vrchy Mts. and Spišská Magura Mts., as re mains of an ex ten sive fore-arc ba sin.
Dif fer ent opin ions have been ex pressed as re gards the tec - tonic evo lu tion of the KB. The stud ies of Andrusov (1974), Krobicki et al. (2003), Golonka et al. (2019), and oth ers sum ma - rized the de vel op ment of the KB as rep re sent ing two main oro - gen et ic phases: a Laramian Late-Cre ta ceous (Mesoalpine) phase, which gave rise to the sys tem of north-vergent nappes af ter subduction of the South Penninic ocean be tween the IWC and Mid dle Penninic con ti nen tal rib bon (Oravic base ment); and a post-Paleogene (Neoalpine) phase, when the orig i nal mor - phol ogy was seg mented into to day’s iso lated blocks. Early stages of the evo lu tion of the KB were stud ied, e.g., by Nemèok and Nemèok (1994), Oszczypko (2006), and Plašienka (2012).
Fig. 2. Po si tion of mea sured new MT sites (yel low cir cles) on the pro files Zaz-1, Or-1, Les-1, re mod eled MT-4, and older sites used in mod el ling along the pro files 2T and S-1 in pre vi ous stud ies (grey cir cles)
Geo log i cal con text af ter Lexa et al. (2000): 7 – Magura Unit of the Flysch Belt: r – Raèa, b – Bystrica, k – Krynica Nappe, 10 – Klippen Belt, 12 – Neo gene de pos its, 14 – Neo gene vol ca nic rocks, 17 – In ner West ern Carpathian Paleogene units, 19 – Tatricum Unit: a – crys tal line base - ment, b – Me so zoic sed i men tary cover, 20 – Veporicum Unit: a – crys tal line com plexes, b – Me so zoic sed i men tary cover, 21 – Fatricum, 22 – Hronicum
The sedimentological stud ies of Mišík et al. (1981), Marschalko (1986), Oszczypko et al. (2005), and oth ers were an im por tant tool for the palaeotectonic re con struc tions. Some stud ies de - scribed a large pro por tion of olistoliths in the com po si tion of the KB (Nemèok, 1980; Golonka et al., 2015). Nev er the less, tec - tonic stud ies dom i nate as re gards the KB, es pe cially those con - cern ing subduction and transpression pro cesses (e.g., Birken - majer, 1986; Ratschbacher et al., 1993; Oszczypko et al., 2010;
Jurewicz, 2018; Ludwiniak, 2018).
One of the most dis cussed ques tions con cerns which ex - actly units be long to the KB. In the Gen eral Geo log i cal Map of Slovakia at 1:200,000 (Bezák, 2008), this is sue was re solved by con ven tion ally de fin ing the KB sensu lato as a trans - pressional Neo gene tec tonic struc ture. In the for ma tion of this struc ture, in ad di tion to the KB sensu stricto, neigh bour ing units of the IWC and FB also took part. The pre vi ous de vel op ment of the KB sensu stricto units can only be spec u lated on in di rectly, us ing the the li thol ogy of the suc ces sions and anal o gies with other South penninic units, es pe cially in the East ern Alps. While in the Alps units of the Mesoalpine orog eny are cov ered by mas sive Austroalpine nappes and come to the sur face only in tec tonic win dows (Rechnitz, Tauern), the struc ture of the IWC only con tains frag ments of them in the fore land of the trans - ported IWC Block. In the deeper struc ture, we also in fer the pres ence of con ti nen tal rib bons (rel ics of Mid dle Penninic-type crust), which have been re ferred to as Oravic base ment or as Pieninic crust (e.g., Grad et al., 2006). These geo log i cal la bels are used in our pro files.
Those seis mic sec tions that have pen e trated the KB (e.g., Tomek and Hall, 1993; Janik et al., 2009; Hrubcová et al., 2010) in di cate its rel a tively shal low depth, al though in ter pre ta tion is dif fi cult be cause of the steep in cli na tion of the struc tures. In each case, the KB does not re sem ble an im por tant su ture zone, which has to be found at the bor der of EP and IWC. We sup - pose that this bor der is in di cated by the Carpathian Con duc tiv - ity Anom aly Zone (CCA), which is the most sig nif i cant lin ear con duc tive crustal struc ture along the Carpathian Arc at a depth of 10–20 km (Jankowski et al., 1977; Buryanov et al., 1987). The CCA has been in ves ti gated by the magneto varia - tional method (Èerv et al., 2001; Kováèiková et al., 2005), which de tects only mag netic com po nents in sound ing, and the magneto telluric (MT) method, which com bines mag netic and elec tric fields, in deep pro files cross ing the Vysoké Tatry Mts.
(Ernst et al., 1997) and east ern Slovakia (Ádám et al., 1997).
The most ac cepted hy poth e sis for the higher con duc tiv ity in - volves pe trol ogy, via the pres ence of min er al ized wa ter or of graph ite (Vanyan, 1997; Hvoždara and Vozár, 2004; Jankowski et al., 2008; Majcin et al., 2014).
METHODS
In our study, we used the MT method, which uti lizes nat u - rally oc cur ring tem po ral vari a tions in the elec tro mag netic field to im age the subsurface dis tri bu tion of elec tri cal con duc tiv ity (Tikhonov, 1950; Cagniard, 1953). We fo cused on MT mea - sure ments along two NW–SE ori ented pro files cross-cut ting the KB in the Zázrivá area (west ern seg ment). The sec tions were
sit u ated to the west (Zaz-1 pro file) and east (Or-1 pro file) of the Zázrivá Fault Zone, as dif fer ent tec tonic styles are in ferred on both sides of this per pen dic u lar trans form fault. In the east ern seg ment of KB, we mea sured one NW–SE ori ented pro file in the Lesnica area in the Pieniny re gion (Les-1 pro file). The lo ca - tion of pro files mea sured is shown in Fig ure 2. We re mod eled also older data along the MT-4 pro file par al lel to Les-1 (Fig. 2).
The geo log i cal sit u a tion of all pro files mea sured is sim i lar.
The two west ern pro files start in the FB, cross the KB and the In ner Carpathian Paleogene (ICP), and end in Fatricum and Tatricum (Zaz-1), or Hronicum (Or-1); the east ern pro file starts in the north ern part of the KB and con tin ues to the ICP. The in - ter pre ta tion of MT mea sure ments (the mod els in Figs. 3 and 4) was aided by the con duc tiv ity con trast be tween the lithological con tents of par tic i pat ing tec tonic units (in gen eral, the least con - duc tive struc tures are the crys tal line rocks of the IWC and PC, more con duc tive are the Me so zoic rocks of the IWC and KB, and the most con duc tive are the Paleogene de pos its of the FB and ICP and the fault and aqui fer zones).
In to tal, 26 points have been mea sured by broad band MT in stru ments (Metronix GmbH GMS-07e) with in duc tion coil mag netic sen sors. The MT data col lected were pro cessed to im ped ance trans fer func tions and mod elled by MT in ver sion codes to es ti mate the best-fit ting 3D con duc tiv ity model. The pro cess ing of MT data was per formed by a Metronix Mapros pro cess ing pack age (Friedrichs, 2003) with im ple men ta tion of the ro bust method. Dif fer ent re jec tion tech niques were used to es ti mate the im ped ance trans fer func tion in the 0.0001 to 100 sec onds range. The data qual ity near the Zázrivá Fault of the sound ing curves de creased to the south due to the pres ence of a DC trac tion rail way and most of the pe ri ods >1 sec ond were dis torted, these pe ri ods not be ing used in the fi nal mod - els. In Ap pen dix 1* we show typ i cal sound ing curves for sites lo cated in the OWC and IWC. For the west ern sites, more con - duc tive shal low struc tures and higher ap par ent resistivities for lon ger pe ri ods are typ i cal. The sta tions clos est to DC rail way are heavily dis torted at lon ger pe ri ods. The east ern MT sound - ing curves show the more re sis tive shal low struc tures of the IWC.
As stated above, the mod el ling was di vided into two sep a - rate mod el ling ar eas with 19 new sites in the west with ad di - tional in for ma tion from the old 2T MT pro file (15 sites) and the 7 new sites in the east, where 9 older sites were added for mod el - ing. The full im ped ance ten sor data were in verted by 3D Mo - dEM in ver sion code (Egbert and Kelbert, 2012; Kelbert et al., 2014), which al lows par al lel cal cu la tion of the in ver sion of im - ped ance on the High Per for mance Com put ing clus ter. We de - cided to use 3D in ver sion of MT data dis trib uted along the pro - file to avoid prob lems with 3D ef fects and its artefacts in 2D de - com posed data, which can lead to un real struc tures within the 2D in ver sion model. Us ing 3D mod el ling in stead of 2D is a com - mon prac tice in the geoelectrical com mu nity (Meqbel et al., 2016; Kirkby and Duan, 2019). Par tic u larly for the Zázrivá area, 3D mod el ling is nec es sary due to the off set of the KB, which can lead to miss ing well-known re gional crustal struc tures as shown by Vozár et al. (2021) by com par i son to older 2D and newly de - vel oped 3D mod els. Also, in the east there are ex pected to be per pen dic u lar struc tures with a strong change in geoelectrical strike an gle. The di men sional anal y sis of in verted new MT data
4 Vladimír Bezák et al. / Geological Quarterly, 2021, 65: 25
* Supplementary data associated with this article can be found, in the online version, at doi: 10.7306/gq.1595
Fig. 3. Geo log i cal in ter pre ta tion of the sec tions Or-1 (up per part) and Zaz-1 (lower part) from the west ern 3D geolectrical model
FB – Flysch Belt, KB – Klippen Belt, PC – Pieninic crust, ICP – In ner West ern Carpathian Paleogene de pos its, M – Me so zoic units un di vided (cover units and nappes), T – Tatricum crys tal line base ment; open ar row head – back-thrust ing,
sim ple ar row head – youn ger short en ing, dashed lines – faults (nor mal and strike-slip)
Fig. 4. Geo log i cal in ter pre ta tion of the sec tions Les-1 (up per part) and MT-4 (lower part) from the east ern 3D geolectrical model Filled ar row head – thrust ing, open ar row head – backthrusting; dashed lines – faults (nor mal and strike-slip);
for other ex pla na tions see Fig ure 3
based on phase ten sors (Caldwell et al., 2004) are in cluded in the sup ple men tary part (Ap pen dix 2), where a mag ni tude skew an gle over 3 in di cates 3D subsurface struc tures.
Af ter pre lim i nary test ing of start ing in ver sion and reg u lar iza - tion pa ram e ters, a start ing half-space model with 100 Wm re sis - tiv ity was used in the fi nal best-fit ting in ver sion model. The fi nal nor mal ized RMS for the Zázrivá model was 2.55 and 2.24 for the Lesnica area (Ap pen di ces 3 and 4).
RESULTS
In the Or-1 sec tion (up per part of Fig. 3), flysch strata show the high est con duc tiv ity in the outer FB as well as in the ICP. KB com plexes have a lower con duc tiv ity, in par tic u lar for the Zaz-1 sec tion (lower part of Fig. 3). Crys tal line rocks in the Pieninic crust (PC) fol low ing Grad et al. (2006) i.e. Pieninic (or Oravic) base ment, as well as in the Tatricum Unit, are very re sis tive.
The rocks of the Me so zoic are also very re sis tive un less con - duc tive wa ter and crushed zones are pres ent. Con tam i na tion by con duc tive flu ids and frac tured zones are vis i ble be tween points 7 and 8 in pro file Or-1 (in the area of the Choèské vrchy Mts.) as well as on the north ern slopes of the Malá Fatra Mts.
be tween sites 8 to 10 in the Zaz-1 sec tion. In cross-sec tions Les-1 and MT-4 (Fig. 4) there are con trast ing re sis tive KB com - plexes with un der ly ing con duc tive FB se quences. The only con duc tive lev els are in ICP suc ces sions and also in a small part of the KB (prob a bly com pris ing shale and sand stone). It is pos si ble to dis tin guish two sub-units ac cord ing to Jurewicz (1997) – an up per Pieninic Nappe with vari able li thol ogy and a lower more ho mo ge neous part of a subpieninic nappe. Qua ter - nary wa ter-sat u rated units prob a bly ex ist at shal low depths near sites 6 (Les-1) and 1 (MT-4). We in fer the ex is tence of a nar row pro trud ing part of the KB with PC crust in their base ment (Fig. 4).
Both sec tions through the 3D MT model of the west ern seg - ment (Zaz-1, Or-1; Fig. 3) share the same mean fea ture – the move ment of FB suc ces sions to the south through KB com - plexes and their bed rock (PC). In the Or-1 pro file, we can iden - tify the overthrust of KB com plexes to gether with the PC onto the IWC units (ICP, Me so zoic suc ces sions, and Tatricum crys - tal line rocks). This is in di rect con trast to the mod els in the east - ern part (Fig. 4) where KB com plexes are torn off from their bed rock and overthrusted onto the FB suc ces sions.
The back overthrust of the south ern part of the FB in the west ern sec tion was for merly mostly in ter preted as con nected with strike-slip move ment (e.g., Kováè and Hók, 1996; Pešková et al., 2009; Teïák et al., 2016). Ac cord ing to the re sults from some seis mic sec tions and the 3D MT model on the 2T seis mic sec tion (Vozár et al., 2021), the po si tion of the KB could be pri - mar ily the re sult of ini tial subduction-collisional pro cesses. The KB in this pro cess, with the south ern most part of the FB and the north ern most units of the IWC, formed a re verse (in this case south ern) wing of the flower struc ture (retroarc thrust ing). It fol - lows that the subduction zone was lo cated N of the KB, ap prox i - mately in the area of the CCA man i fes ta tions, as we ear lier in - ferred (Kuchariè et al., 2013).
This type of flower struc ture, cre ated dur ing subduction and oblique col li sion, is gen er ally de scribed in Dadlez and Jaro - szewski (1994), Press et al. (2004), Yeats (2012), and oth ers.
For our re gion it was pro posed by Birkenmajer (1986). All other tec tonic pro cesses then mod i fied the orig i nal struc ture to vary - ing de grees. These mainly in cluded the transpressional move - ments, but the Zaz-1 sec tion also shows the ef fect of youn ger com pres sion and the emer gence of a steep fault bound ary of
the KB in the south against the IWC units (lower part of Fig. 3).
The trans verse Zázrivá Fault runs be tween our sec tions Zaz-1 and Or-1. The changes on both sides of this fault were ini ti ated pos si bly also by the mor phol ogy of the EP. We tried to iden tify this fault by 3 ex tra broad band MT sites sit u ated along the east-west line, and also by a short con trol source MT pro file which crossed this fault struc ture. Un for tu nately, the data from all broad band MT sites were heavily dis torted and could not be used in mod el ling. The con trol source pro file is very shal low and was not able to iden tify deeper struc tures as so ci ated with the fault.
By con trast, we clearly see the orig i nal po si tion of the KB in the east ern sec tion (Les-1 and MT-4 slices of 3D east ern mod - els, Fig. 4) as part of the accretionary prism in the over bur den of the flysch nappes. Pre vi ous work ers also ar rived at the same re sults based on de tailed struc tural re search (Jurewicz, 1997, 2018; Oszczypko et al., 2010; Plašienka et al., 2012). This po si - tion is only slightly mod i fied in some places by later backthrusts (Plašienka et al., 2013). The accretionary prism is mostly boun - ded to the south (on the bound ary with the ICP) by a steep fault (Podhale Fault) de scribed in sev eral pre vi ous stud ies (e.g., Jurewicz, 1997; Ludwiniak, 2018), which has also been iden ti - fied in older MT pro files (Majcin et al., 2018). A fault bound ary is pres ent also on the north ern side of the KB or some times within the KB. This is ap par ently the con se quence of transpressional tec ton ics. In this way, all of the wide KB zone should be seg - mented into more parts (e.g., Šariš tran si tional zone in the sense of Jurewicz, 2018, the zone with only KB with its PC base ment, and an in ter nal zone where the orig i nal po si tion of the KB with PC un der IWC com plexes is sup posed to be (e.g., MT-4 pro file or older MT-15 pro file; Bezák et al., 2014).
DISCUSSION
The tec tonic de vel op ment of the KB is seen as an in di ca tor of the char ac ter of tec tonic pro cesses be tween the IWC Block and EP due to its po si tion on the bound ary of the OWC and IWC. There is an ob vi ous dif fer ence be tween the types of tec - tonic re gime in the west ern and east ern seg ments. An accretio - nary wedge of a flower shape was formed in its west ern sec tion in the first stages of subduction and oblique col li sion. It is iden ti - fied in the deep MT 3D model along the 2T seis mic pro file (Vozár et al., 2021). The south ern most parts of the FB and KB units are lo cated in the re versed wing of this flower struc ture, which is shifted to the south to gether with part of the fron tal In - ner-Carpathian units. This type of col li sion rap idly changed in this seg ment into a transpressional re gime. The con tact be - tween the EP and the IWC in west ern Slovakia is ex pressed as a shear-zone (in the area of the CCA), as iden ti fied by sec tion MT-15 (Bezák et al., 2014). The EP is rep re sented here by the Cadomian com plexes of Brunia (Dudek, 1980). A sud den change in the Moho depth at this con tact in seis mic (Hrubcová et al., 2010) and gravimetric (Bielik, 1995) mod els has been iden ti fied. The traces of early subduction be came ob scured by these youn gest tec tonic move ments in a transpressional re - gime. The transpression is also as so ci ated with the for ma tion of the youn ger fan struc ture of the KB.
Mainly or thogo nal subduction and col li sion took place in the NE part of the WCp as shown by the pri mary po si tion of KB, which be came part of the FB accretionary wedge. Only in the fi nal stages, when the subduction zone moved to the East Carpathians, did the the re gime change to transpressional (e.g., Ratschbacher et al., 1993) ac com pa ny ing re vers ing
6 Vladimír Bezák et al. / Geological Quarterly, 2021, 65: 25
over thrusts and strike-slip faults along side the KB (Plašienka et al., 2013).
These dif fer ences be tween the west ern and east ern parts of the WCp in the tec tonic re gime of the Neoalpine col li sion of the IWC and EP are also re flected in the in ter nal struc tures of the IWC Block it self, which can be di vided into two sub-blocks (Fig. 5).
The west ern sub-block is prin ci pally char ac ter ized by trans pressional move ments on mostly NE-ori ented faults, shown in the tec tonic scheme af ter Lexa et al. (2000) in Fig ure 5, which were ac ti vated dur ing oblique col li sion. The most im - por tant shear zones with strike-slip move ments in clude the tec tonic zone at the mar gin of the EP, ac com pa nied by the CCA, as well as other sig nif i cant tec tonic zones such as the Carpa thian Shear Cor ri dor (Marko et al., 2017) shown in Fig - ure 6, and the zone around the KB it self with a typ i cal flower struc ture. This struc ture was high lighted by the move ments on nor mal faults in the sub se quent transtensional stage. They are the pri mary cause of the for ma tion of the so-called core moun tains (horsts) and intramontane de pres sions (grabens) filled mainly with Neo gene de pos its (a ba sin and range struc -
ture). The trans pressio nal move ments also re sulted in the emer gence of Neo gene bas ins (such as the Vi enna and Orava bas ins) that over lap the orig i nal collisional zone and also the KB (Fodor, 1995; Ludwiniak et al., 2019).
The east ern sub-block of the IWC (Fig. 5) rep re sents the part of the IWC that col lided or thogo nally with the EP in the NE part of the WCp Arc. In the struc ture of this block, there are no ba sin and range struc tures, but it con tains com pact em bed ded mas sifs such as the Veporské and Gemerské Rudohorie Mts.
There are no sig nif i cant Neo gene faults, ex cept for the N–S youn gest faults (Branisko, Štítnik, Hornád; Fig. 6). Most strike - -slip faults in this sub-block were ac tive dur ing pre vi ous stages of tec tonic evo lu tion (in Me so zoic and part of Late Pa leo zoic time; Bezák, 2002). An ex am ple is one of the most fa mous WCp faults, which is per haps the most eas ily vis i ble fault on sat el lite im ages. This is the Muráò Fault in the mid dle of the Veporic Mas sif, which has the char ac ter of a strike-slip fault of NE ori en ta tion (Pospíšil et al., 1989), which does not con tinue ei ther into ICP strata to the NE nor into neovolcanic rocks to the SW.
Fig. 5. Scheme of IWC tec tonic sub-blocks and their rel a tive move ment dur ing the Neo gene (made with the use of the tec tonic scheme of Lexa et al., 2000)
EP – Eu ro pean plat form, FBw – west ern part of the Flysch Belt, FBe – east ern part of the Flysch Belt, FBa – Flysch Belt in the Alps, KBw – west ern seg ment of the Klippen Belt, KBe – east ern seg ment of the Klippen Belt, EA – pre-Ce no zoic com plexes in the East ern Alps and in the Vi enna Ba sin base ment. Phf – Osrblie-Pohorelá shear zone. Faults: Rb – Raba, Hu – Hurbanovo, Ds – Diosjeno, Lt – Leitha, Zz – Zázrivá, Pr – Prosiek, Ru – Ružbachy, Mu – Muráò; CCA – po si tion of the Carpathian Con duc tive Zone (Èerv et al., 2001); some core moun - tains: MK – Malé Karpaty, PIn – Považský Inovec, Tr – Tríbeè, T – Tatry, NT – Nízke Tatry
The bound ary be tween the west ern and east ern seg ments of the KB is prob a bly lo cated to the east of the Prosiek Fault (Pr), in the area where the Carpathian Arc di rec tion changes.
The mar ginal NE part of the west ern sub-block (to the SE of the Prosiek Fault; Fig. 5) was prob a bly also in volved in the or thogo - nal col li sion. This is also shown by the pres ence of a subduction root on the gravimetric model of this area (Dérerová et al., 2020). The change of tec tonic re gime in this part of the sub - -block from transpression to col li sion was prob a bly caused by a change in the ge om e try of the EP mar gin (from SW–NE to NW–SE ori en ta tion). In this part of the Fatra-Tatra sub-block, E–W faults are al ready de vel oped (e.g., in the area of the Tatry Mts. and Vikartovce Ridge; Fig. 5), which to gether with the breaks in the N–S trending faults in the east ern sub-block are due to youn ger ex ten sion.
The po si tion of strike-slip faults in the west ern seg ments is also vis i ble on the gravimetric map of Bouguer anom a lies (Pašteka et al., 2017; Fig. 6). The ar eas with high est Bouguer anom aly gra di ents on this map rep re sent tec tonic in ter faces of blocks with dif fer ent den si ties. These in ter faces are in agree - ment with faults in the tec tonic scheme in Fig ure 5, fol low ing Lexa et al. (2000). Many of the faults in di cated are still ac tive even to day, as shown by the lo ca tion of earth quake epi centres in the last two de cades (Cipciar et al., 2020; Fig. 6). The depth of epi centres is not in di cated, be cause they are not very well con strained and ex hibit high un cer tainty. It is sig nif i cant that cer tain smaller ac tiv ity on these faults per sist till now. Gen er ally, most of the epi centres are sit u ated at depths of 1–15 km, and few of them are deeper than 20–25 km (these are sit u ated near
the Hurbanovo Fault, and near CSC faults). A sim i lar pat tern is shown by mag ni tude dis tri bu tion, where the stron gest earth - quakes in the area stud ied are near the Hu, CSC, Pr and Phf faults (Fig. 6).
The greater ex tent of the col li sion in the NE of the WCp in the fore land of the Vepor-Gemer sub-block is re flected also by the dis pro por tion ately greater width of the FB com pared to that in the west ern sec tor (see e.g., Lexa et al., 2000), and also by the typ i - cal large fore-arc ba sin of the ICP (Podhalie, Levoèské vrchy Mts., Spišská Magura Mts.). Also, the char ac ter of vol ca nism may be ev i dence for this in ter pre ta tion. Neo gene vol ca nism in cen tral Slovakia is con nected to the evo lu tion of the cen tral astenolith be neath the Pannonian Ba sin and with the or i gin of the ba sin and range struc ture. By con trast, the vol ca nism in east ern Slovakia is as so ci ated with subduction (Koneèný et al., 2002).
The Osrblie-Pohorelá Fault sys tem (Phf in Figs. 5 and 6) was iden ti fied as a sig nif i cant in ter face in the crust by geo phys i - cal mod el ling (Bezák et al., 2020) and it rep re sents the bound - ary be tween the west ern and east ern sub-blocks. The Phf was a kind of trans form fault sys tem dur ing Neo gene subduction. It spa tially fol lows the Rb Fault (Fig. 5), which di vided mostly East ern Alps pre-Ce no zoic units from the Pelso Block. South of the east ern sub-block there are also other ter ranes of the Panno nian area which grad u ally be came in volved in the col li - sion pro cess with the EP (Pelso, Bukk and Zemplín blocks).
Af ter subduction moved far ther to the east (to the East ern Carpathians), the KB, FB, and parts of the EP units to gether with the east ern part of the IWC be came the up per plate in re la tion to subduction and en tered a transtensional re gime. This also al -
8 Vladimír Bezák et al. / Geological Quarterly, 2021, 65: 25
Fig. 6. Bouguer anom aly con tour map of the area in ves ti gated, with epi centres of earth quakes dur ing the last 20 years (af ter Cipciar et al., 2020)
Faults: Rb – Rába, Hu – Hurbanovo, Zz – Zázrivá, Pr – Prosiek, Tt – Tatry, Vi – Vikartovce, Nt – Nízke Tatry, Ru – Ružbachy, St – Štítnik Ro – Rožòava, Br – Branisko, Hn – Hornád, Ds – Diosjeno. The line la belled as CCA1 is the po si tion of the CCA based on Jankowski et al.
(1985), the CCA2 line fol lows Èerv et al. (2001), and the CCA line is our in ter pre ta tion; CSC – Carpathian shear cor ri dor, Phf – Osrblie-Pohorelá shear zone
lowed the pen e tra tion of vol ca nism de scribed by e.g. Birken - majer et al. (2004), Kuchariè et al. (2013) to the north, be yond the for mer bound ary of the subduction zone and north of the KB.
CONCLUSIONS
MT sound ing in pro files across the west ern and east ern seg ments of the KB and OWC and IWC con tact zone re vealed im por tant dif fer ences in their deep tec tonic struc tures and thus also in the tec tonic style in both seg ments. We in fer the in ter - face po si tion be tween struc tures to the east from the Pr and Ru faults, where the ori en ta tion of the Carpathian Arc axis also changes. It would be ap pro pri ate to fo cus fur ther geo phys i cal re search on this key area.
In the west ern seg ment, af ter a short pe riod of subduction, oblique col li sion took place and a transpressional re gime be - came dom i nant. The po si tion of the KB in the backthrust to the south is at trib uted to a transpressional mode by most au thors.
We in ter pret that this po si tion was in her ited from the pre vi ous stage of subduction and early col li sion. This po si tion was in many places sub se quently re worked dur ing the transpressional stage af ter subduction and col li sion moved into the east ern seg ment.
The east ern seg ment mainly ex pe ri enced di rect or thogo nal subduction and col li sion and overthrusts of the FB accretionary
prism to NE. FB thrusts also mostly in clude the KB units, which is in agree ment with struc tural mod els de scribed by ear lier au - thors. Even these units were re worked in the south ern part when the re gime changed to transpressional.
Based on the dif fer ent tec tonic re gimes in the west ern and east ern seg ments of the KB, we di vide the IWC Block into two sub-blocks (Fig. 5). The dif fer ences of KB tec tonic struc tures in the west and the east of the area stud ied, in di cated by our MT mod els, are in ter preted as dif fer ent modes of these IWC sub- blocks’ in ter ac tion with the EP. The west ern sub-block was mostly in an oblique col li sion mode with a pre dom i nantly trans - pressional re gime, while the east ern sub-block was pre dom i - nantly in or thogo nal col li sion with thrust ing tec ton ics to the NE.
The di vid ing tec tonic trans for ma tion zone be tween these sub- blocks was the Phf Fault sys tem. This dif fer ence in tec tonic re - gimes is also re flected in the in ter nal struc tures of both sub- blocks.
Ac knowl edge ments. The au thors would like to thank the re view ers M. Ludwiniak, L. Jankowski and M. Stefaniuk for their cru cial com ments, which helped im prove the manu script. The work was ac com plished with sup port from pro ject APVV 16-0482 and pro ject VEGA 2/0047/20. We thank J. Telecký, D. Bilèík, A. Marseniè, J. Madzin for help with field work, L. Bittó for tech ni cal and graph i cal sup port dur ing manu script prep a ra - tion, and J. Pek for his con sul ta tion re gard ing MT meth ods.
REFERENCES
Ádám, A., Ernst, T., Jankowski, J., Jozwiak, W., Hvozdara, M., Szarka, L., Wesztergom, V., Logvinov, I., Kulik, S., 1997.
Elec tro mag netic in duc tion pro file (PREPAN95) from the East Eu ro pean Plat form (EEP) to the Pannonian Ba sin. Acta Geodetica et Geophysica Hungarica, 32: 203–223.
Andrusov, D., 1974. The Pieniny Klippen Belt (the Carpathians of Czecho slo va kia). In: Tec ton ics of the Carpathian-Bal kan re - gions (ed. M. Mahe¾): 145–148. Geo log i cal In sti tute of Dionýz Štúr, Bratislava.
Beidinger, A., Decker, K., 2016. Paleogene and Neo gene ki ne mat - ics of the Al pine-Carpathian fold-thrust belt at the Al pine- Carpathian tran si tion. Tectonophysics, 690: 263–287.
Bezák, V., 2002. Hercynian and Al pine strike-slip tec ton ics – a dom - i nant el e ment of tec tonic de vel op ment of the In ner West ern Carpathians. Geologica Carpatica, 53, Spe cial Is sue: 17–22.
Bezák, V. ed., 2008. Gen eral geo log i cal map of the Slo vak Re pub lic 1:200 000. State Geo log i cal In sti tute of Dionýz Štúr, Bratislava.
Bezák, V., Jacko, S., Janák, M., Ledru, P., Petrík, I., Vozárová, A., 1997. Main Hercynian lithotectonic units of the West ern Carpa - thians. In: Geo log i cal evo lu tion of the West ern Carpathians (eds. P. Grecula, D. Hovorka and M. Putiš): 261–268. Mineralia Slovaca – Mono graph.
Bezák, V., Broska, I., Ivanièka, J., Reichwalder, P., Vozár, J., Polák, M., Havrila, M., Mello, J., Biely, A., Plašienka, D., Potfaj, M., Koneèný, V., Lexa, J., Kalièiak, M., Žec, B., Vass, D., Eleèko, M., Janoèko, J., Pereszlényi, M., Marko, M., Maglay, J., Pristaš, J., 2004. Tec tonic map of the Slo vak Re - pub lic 1:500 000. State Geo log i cal In sti tute of Dionýz Štúr, Bratislava.
Bezák, V., Biely, A., Eleèko, M., Koneèný, V., Mello, J., Polák, M., Potfaj, M., 2011. A new syn the sis of the geo log i cal struc ture of Slovakia – the gen eral geo log i cal map at 1:200 000 scale. Geo - log i cal Quar terly, 55 (1): 1–8.
Bezák, V., Pek, J., Vozár, J., Bielik, M., Vozár, J., 2014. Geoelectri - cal and geo log i cal struc ture of the crust in West ern Slovakia.
Studia Geophysica et Geodaetica, 58: 473–488.
Bezák, V., Pek, J., Vozár, J., Majcin, D., Bielik, M., Tomek, È., 2020. Geoelectrically dis tinct zones in the crust of the West ern Carpathians?: a con se quence of Neo gene strike-slip tec ton ics.
Geologica Carpathica, 71: 14–23.
Bielik, M., 1995. Con ti nen tal con ver gence in the area of the West - ern Carpathians on the ba sis of den sity mod el ing. Geologica Carpathica, 46: 3–12.
Bielik, M., Tášárová, Z.A., Vozár, J., Zeyen, M., Guterch, A., Grad, M., Janik, T., Wybraniec, S., Götze, H.-J., Dérerová, J., 2010.
Grav ity and seis mic mod el ing in the Carpathian-Pannonian Re - gion. In: Variscan and Al pine Ter ranes of the Circum-Pannonian Re gion (eds. J. Vozár, F. Ebner, A. Vozárová, J. Haas, S.
Kovács, M. Sudar, M. Bielik and C. Péró): 202–233. Geo log i cal In sti tute, SAS, Bratislava.
Biely, M., 1989. The geo log i cal struc ture of the West ern Carpathians. Mémoires de la Société Géologique de France, 154: 51–57.
Birkenmajer, K., 1986. Stages of struc tural evo lu tion of the Pieniny Klippen Belt, Carpathians. Studia Geologica Polonica, 88: 7–32.
Birkenmajer, K., Pécskay, Z., Szeliga, W., 2004. Age re la tion ships be tween Mio cene vol ca nism and hy dro ther mal ac tiv ity at Mt.
Jarmuta, Pieniny Klippen Belt, West Carpathians, Po land.
Studia Geologica Polonica, 123: 279–294.
Buryanov, V.B., Gordyenko, V.V., Zavgorodnyaya, O.V., Kulik, S.
N., Logvinov, I. M., Shuman, V.H., 1987. Geofizicheskiy model tektonosfery Evropy (in Rus sian). Naukova Dumka, Kiev.
Cagniard, L., 1953. Ba sic the ory of the mag neto-tel lu ric method of geo phys i cal pros pect ing. Geo phys ics, 18: 605–635.
Caldwell, T.G., Bibby, H.M., Brown, C., 2004. The magnetotelluric phase ten sor. Geo phys i cal Jour nal In ter na tional, 158: 457–469.
Cipciar, A., Šugár, M., Csicsay, K., Kristeková, M., Fojtíková, L., Kysel, R., Pažák, P., Bystrický, E., Gális, M., Kristek, J.,
Moczo, P., 2020. Slo vak Earth quakes Cat a logue, Ver sion 2020.
Earth Sci ence In sti tute of the Slo vak Acad emy of Sci ences.
Csontos, L., Nagymarosy, A., Horváth, F., Kováè, M., 1992. Ter - tiary evo lu tion of the Intracarpathian area: a model. Tectono - physics, 208: 221–241.
Èerv, V., Kováèiková, S., Pek, J., Pìèová, J., Praus, O., 2001.
Geoelectrical struc ture across the Bo he mian Mas sif and the tran si tion zone to the West Carpathians. Tectonophysics, 332:
201–210.
Dadlez, R., Jaroszewski, W., 1994. Tektonika (in Pol ish). Wyda - wni ctwo Naukowe PWN, Warszawa.
Dérerová, J., Bielik, M., Kohút, I., Godová, D., Vozár, J., Bezák, V., 2020. Lithospheric model along transect HT-1 across West - ern Carpathians and Pannonian Ba sin based on 2D in te grated mod el ling. Con tri bu tions to Geo phys ics and Ge od esy, 50:
463–474.
Dudek, A., 1980. The crys tal line base ment block of the Outer Carpathians in Moravia: Bruno-Vistulicum. Rozpravy Èesko - slovenské akademie vìd – øada matematických a pøírodních vìd, 8: 1–85.
Egbert, G.D., Kelbert, A., 2012. Com pu ta tional rec i pes for elec tro - mag netic in verse prob lems. Geo phys i cal Jour nal In ter na tional, 189: 251–267.
Ernst, T., Jankowski, J., Semenov, V.Y., Ádám, A., Hvoždara, M., Jozwiak, W., Lefeld, J., Pawliszyn, J., Szarka, L., Wesztergom, V., 1997. Elec tro mag netic soundings across the Tatra Moun tains. Acta Geophysica Polonica, 45: 33–44.
Fodor, L., 1995. From transpression to transtension: Oligo - cene–Mio cene struc tural evo lu tion of the Vi enna ba sin and the East Al pine-West ern Carpathian junc tion. Tectonophysics, 242:
151–182.
Fodor, L., Csontos, L., Bada, G., Györfi, I., Benkovics, L., 1999.
Ter tiary tec tonic evo lu tion of the Pannonian Ba sin sys tem and neigh bour ing orogens: a new syn the sis of palaeostress data.
Geo log i cal So ci ety Spe cial Pub li ca tions, 156: 295–334.
Friedrichs, B., 2003. Mapros (Ver. 0.87b freeware), Metronix Mea - sure ment In stru ments and Elec tron ics Ltd., https://www.metro - nix.de/metro nixweb/en/geophysik/doc u ments/.
Froitzheim, N., Plašienka, D., Schuster, R., 2008. Al pine tec ton ics of the Alps and West ern Carpathians. In: The Ge ol ogy of Cen - tral Eu rope (ed. T. McCann): 1141–1232. Geo log i cal So ci ety Pub lish ing House, Lon don.
Golonka, J., Aleksandrowski, P., Aubrecht, R., Chowaniec, J., Chrustek, M., Cieszkowski, M., Florek, R., Gawêda, A., Jaro - siñski, M., Kêpiñska, B., Krobicki, M., Lefeld, J., Lewando - wski, M., Marko, F., Michalik, M., Oszczypko, N., Picha, F., Potfaj, M., S³aby, E., Œl¹czka, A., Stefaniuk, M., Uchman, A.,
¯elaŸniewicz, A., 2005. The Orava Deep Drill ing Pro ject and post-Palaeogene tec ton ics of the North ern Carpathians. Annales Societatis Geologorum Poloniae, 75: 211–248.
Golonka, J., Krobicki, M., Waœkowska, A., Cieszkowski, M., Œl¹czka, A., 2015. Olistostroms of the Pieniny Klippen Belt, North ern Carpathians. Geo log i cal Mag a zine, 152: 269–286.
Golonka, J., Pietsch, K., Marzec, P., Kasperska, M., Dec, J., Cichostêpski, K., Lasocki, S., 2019. Deep struc ture of the Pieniny Klippen Belt in Po land. Swiss Jour nal of Geosciences, 112: 475–506.
Grabowska, T., Bojdys, G., Bielik, M., Csicsay, K., 2011. Den sity and mag netic mod els of the litho sphere along CELEBRATION 2000 pro file CEL01. Acta Geophysica, 59: 526–560.
Grad, M., Guterch, A., Keller, G.R., Janik, T., Hegedûs, E., Vozár, J., Œl¹czka, A., Tiira, T., Yliniemi, J., 2006. Lithospheric struc - ture be neath trans-Carpathian transect from Pre cam brian plat - form to Pannonian ba sin CELEBRATION 2000 seis mic pro file CEL05. Jour nal of Geo phys i cal Re search, 111: B03301.
Gross, P., Filo, I., Halouzka, R., Haško, J., Havrila, M., Kováè, P., Maglay, J., Mello, J., Nagy, A., 1994. Geo log i cal Map of South and East Orava. GÚDŠ, Bratislava.
Haško, J., Polák, M., 1978. Geo log i cal Map of Kysucké vrchy hills and Krivánska Malá Fatra Mts. GÚDŠ, Bratislava.
Hrubcová, P., Šroda, P., Grad, M., Geiss ler, W.H., Guterch, A., Vozár, J., Hegedüs, E., 2010. From the Variscan to the Al pine
Orog eny: crustal struc ture of the Bo he mian Mas sif and the West ern Carpathians in the light of the SUDETES 2003 seis mic data. Geo phys i cal Jour nal In ter na tional, 183: 611–633.
Hvoždara, M., Vozár, J., 2004. Lab o ra tory and geo phys i cal im pli ca - tions for ex pla na tion of the na ture of the Carpathian con duc tiv ity anom aly. Acta Geophysica Polonica, 52: 497–508.
Janik, T., Grad, M., Guterch, A., CELEBRATION 2000 Work ing Group, 2009. Seis mic struc ture of the litho sphere be tween the East Eu ro pean Craton and the Carpathians from the net of CELEBRATION 2000 profiles in SE Po land. Geo log i cal Quar - terly, 53 (1): 141–158.
Jankowski, J., Szymañski, A., Pìè, K., Èerv, V., Petr, V., Pìèová, J., Praus, O., 1977. Anom a lous in duc tion in the Carpathians.
Studia Geophysica et Geodaetica, 21: 35–57.
Jankowski, J., Tarlowski, Z., Praus, O., Pìèová, J., Petr, V., 1985.
The re sults of deep geo mag netic soundings in the West Carpathians. Geo phys i cal Jour nal of the Royal As tro nom i cal So ci ety, 80: 561–574.
Jankowski, J., JóŸwiak, W., Vozar, J., 2008. Ar gu ments for ionic na ture of the Carpathian elec tric con duc tiv ity anom aly. Acta Geophysica, 56:1–11.
Janoèko, J., Gross, P., Jacko, Jr. S., Buèek, S., Karoli, S., Žec, B., Polák, M., Rakús, M., Potfaj, M., Halouzka, R., 2000. Geo - log i cal Map of Spišská Magura Mts. ŠGÚDŠ, Bratislava.
Jurewicz, E., 1997. The con tact be tween the Pieniny Klippen Belt and Magura Unit (the Ma³e Pieniny Mts.). Geo log i cal Quar terly, 41 (3): 315–326.
Jurewicz, E., 2018. The Šariš Tran si tional Zone, re veal ing in ter ac - tions be tween Pieniny Klippen Belt, Outer Carpathians and Eu - ro pean plat form. Swiss Jour nal of Geosciences, 111: 245–267.
Kelbert, A., Meqbel, N., Egbert, G.D., Tandon, K., 2014. Mo dEM: a mod u lar sys tem for in ver sion of elec tro mag netic geo phys i cal data. Com put ers and Geosciences, 66: 40–53.
Kirkby, A., Duan, J., 2019. Crustal struc ture of the East ern Arunta Re gion, Cen tral Aus tra lia, from magnetotelluric, seis mic, and mag netic data. Jour nal of Geo phys i cal Re search: Solid Earth, 124: 1–20.
Koneèný, V., Kováè, M., Lexa, J., Šefara, J., 2002. Neo gene evo - lu tion of the Carpatho-Pannonian re gion: an in ter play of sub - duction and back-arc diapiric up rise in the man tle. EGU Stephan Mueller Spe cial Pub li ca tion Se ries, 1: 105–123.
Kováè, P., Hók, J., 1996. Ter tiary de vel op ment of the west ern part of Klippen Belt. Slo vak Geo log i cal Mag a zine, 2: 137–149.
Kováèiková, S., Èerv, V., Praus, O., 2005. Mod el ling of the con duc - tance dis tri bu tion at the east ern mar gin of the Eu ro pean Hercynides. Studia Geophysica et Geodaetica, 49: 403–421.
Kováèiková, S., Logvinov, I., Tarasov, V., 2019. Com par i son of the 2-D and quasi-3-D geoelectric mod els of the Ukrai nian East ern Carpathians and their link to the tec tonic struc ture. Tec ton ics, 38: 3818–3834.
Krobicki, M., Golonka, J., Aubrecht, R., 2003. Pieniny Klippen Belt: gen eral ge ol ogy and geodynamic evo lu tion. Pub li ca tions of the In sti tute of Geo phys ics, Pol ish Acad emy of Sci ences, M-28:
25–33.
Kuchariè, ¼., Bezák, V., Kubeš, P., Koneèný, V., Vozár, J., 2013.
New mag netic anom a lies of the Outer Carpathians in NE Slovakia and their re la tion ship to the Carpathian Con duc tiv ity Zone. Geo log i cal Quar terly, 57 (1): 123–134.
Lexa, J., Koneèný, V., 1998. Geodynamic as pects of the Neo gene to Qua ter nary vol ca nism. In: Geodynamic De vel op ment of the West ern Carpathians (ed. M. Rakús): 219–240. Geo log i cal Sur - vey of the Slo vak Re pub lic.
Lexa, J., Bezák, V., Eleèko, M., Mello, J., Polák, M., Potfaj, M., Vozár, J. eds., 2000. Geo log i cal Map of the West ern Carpathians and Ad ja cent Ar eas, Scale 1:500000. State Geo - log i cal In sti tute of Dionýz Štúr, Bratislava.
Ludwiniak, M., 2018. Mio cene transpression ef fects at the bound - ary of Cen tral Carpathian Paleogene Ba sin and Pieniny Klippen Belt: ex am ples from Pol ish – Slovakian bor der land. Ge ol ogy, Geo phys ics and En vi ron ment, 44: 91–110.
Ludwiniak, M., Œmigielski, M., Kowalczyk, S., £oziñski, M., Czarniecka, U., Lewiñska, L., 2019. The intramontane Orava
10 Vladimír Bezák et al. / Geological Quarterly, 2021, 65: 25
Ba sin – ev i dence of large-scale Mio cene to Qua ter nary sinistral wrench ing in the Al pine-Carpathian-Pannonian area. Acta Geolo gica Polonica, 69: 339–386.
Majcin, D., Bilèík, D., Kutas, R.I., Hlavòová, P., Bezák, V., Kuchariè, ¼., 2014. Re gional and lo cal phe nom ena in flu enc ing the ther mal state in the Flysch Belt of the north east ern part of Slovakia. Con tri bu tions to Geo phys ics and Ge od esy, 44:
271–292.
Majcin, D., Bezák, V., Klanica, R., Vozár, J., Pek, J., Bilèík, D., Telecký, J., 2018. Klippen Belt, Flysch Belt and In ner West ern Carpathian Paleogene Ba sin re la tions in the North ern Slovakia by magnetotelluric im ag ing. Pure and Ap plied. Geo phys ics, 175: 3555–3568.
Marko, F., Andriessen, P.A.M., Tomek, È., Bezák, V., Fojtíková, L., Bošanský, M., Piovarèi, M., Reichwalder, P., 2017.
Carpathian shear cor ri dor – a strike-slip bound ary of an ex - truded crustal seg ment. Tectonophysics, 703–704: 119–134.
Marschalko, R., 1986. Evo lu tion and geotectonic sig nif i cance of the Klippen Belt Cre ta ceous flysch in the Carpathian mega - struc ture (in Slo vak with Eng lish sum mary). Veda, Bratislava.
Meqbel, N., Weckmann, U., Muñoz, G., Ritter, O., 2016. Crustal meta mor phic fluid flux be neath the Dead Sea Ba sin: con straints from 2-D and 3-D magnetotelluric mod el ling. Geo phys i cal Jour - nal In ter na tional, 207: 1609–1629.
Mišík, M., Jablonský, J., Mock, R., Sýkora, M., 1981. Konglo - merate mit exotischen ma te rial in dem Albder Zentralen West - karpaten – paläogeographische und tektonische In ter pre ta tion.
Acta Geologica et Geographica Universitatis Comenianae, Geologica, 37: 5–55.
Nemèok, J., 1980. Non-tra di tional view of East-Slovakian Klippen Belt. Geologický zborník – Geologica Carpathica, 31: 563–568.
Nemèok, J., 1990. Geo log i cal Map of Pieniny, Èergov Mts., ¼ubo - vnianska and Ondavská vrchovina Mts. GÚDŠ, Bratislava.
Nemèok, M., Nemèok, J., 1994. Late Cre ta ceous de for ma tion of the Pieniny Klippen Belt, West Carpathians. Tectonophysics, 250: 1–28.
Nemèok, M., Pospišil, L., Lexa, J., Donelick, R.A., 1998. Ter tiary subduction and slab break-off model of the Carpathian - -Pannonian re gion. Tectonophysics, 295: 307–340.
Oszczypko, N., 2006. Late Ju ras sic-Mio cene evo lu tion of the Outer Carpathian fold-and thrust belt and its foredeep ba sin (West ern Carpathians, Po land). Geo log i cal Quar terly, 50 (1): 169–194.
Oszczypko, N., Oszczypko-Clowes, M., 2014. Geo log i cal struc - ture and evo lu tion of the Pieniny Klippen Belt to the east of the Dunajec River – a new ap proach (West ern Outer Carpathians, Po land). Geo log i cal Quar terly, 58 (4): 737–758.
Oszczypko, N., Oszczypko-Clowes, M., Golonka, J., Marko, F., 2005. Oligocene-Lower Mio cene se quences of the Pieniny Klippen Belt and ad ja cent Magura Nappe be tween Jarabina and the Poprad River (East Slovakia and South Po land): their tec - tonic po si tion and palaeogeographic im pli ca tions. Geo log i cal Quar terly, 49 (4): 379–402.
Oszczypko, N., Jurewicz, E., Plašienka, D., 2010. Tec ton ics of the Klippen Belt and Magura Nappe in the east ern part of the Pieniny Mts. (West ern Carpathians, Po land and Slovakia) – new ap proaches and re sults. Sci en tific An nals, School of Ge ol ogy, Ar is totle Uni ver sity of Thessaloniki, Spe cial Vol ume, 100:
221–229.
Pašteka, R., Zahorec, P., Kušnirák, D., Bošanský, M., Papèo, J., Szalaiová, V., Krajòák, M., Marušiak, I., Mikuška, J., Bielik, M., 2017. High res o lu tion Slo vak Bouguer grav ity anom aly map and its en hanced de riv a tive trans for ma tions: new pos si bil i ties for in ter pre ta tion of anom a lous grav ity fields. Con tri bu tion to Geo phys ics and Ge od esy, 47: 81–94.
Pešková, I., Vojtko, R.,Starek, D., Sliva, ¼., 2009. Late Eocene to Qua ter nary de for ma tion and stress field evo lu tion of the Orava re gion (West ern Carpathians). Acta Geologica Polonica, 59:
73–91.
Plašienka, D., 2012. Early stages of struc tural evo lu tion of the Carpathian Klippen Belt (Slovakian Pieniny sec tor). Mineralia Slovaca, 44: 1–16.
Plašienka, D., 2018. Con ti nu ity and episodicity in the Early Al pine tec tonic evo lu tion of the West ern Carpathians: how large-scale pro cesses are ex pressed by the orogenic ar chi tec ture and rock re cord data. Tec ton ics, 37: 2029–2079.
Plašienka, D., Grecula, P., Putiš, M., Kováè, M., Hovorka, D., 1997. Evo lu tion and struc ture of the West ern Carpathians: an over view. In: Geo log i cal Evo lu tion of the West ern Carpathians (eds. P. Grecula, D. Hovorka and M. Putiš): 1–24. Mineralia Slovaca, Bratislava.
Plašienka, D., Soták, J., Jamrichová, M., Halásová, E., Pivko, D., Józsa, Š., Madzin, J., Mikuš, V., 2012. Struc ture and evo lu tion of the Pieniny Klippen Belt dem on strated along a sec tion be - tween Jarabina and Litmanová vil lages in East ern Slovakia.
Mineralia Slovaca, 44: 17–38.
Plašienka, D., Józsa, Š., Gedl, P., Madzin, J., 2013. Fault con tact of the Pieniny Klippen Belt with the Cen tral Carpathian Paleogene Ba sin (West ern Carpathians): new data from a unique tem po rary ex po sure in ¼utina vil lage (East ern Slovakia).
Geologica Carpathica, 64: 165–168.
Plašienka, D., Buèová, J., Šimonová, V., 2019. Vari able struc tural styles and tec tonic evo lu tion of an an cient back stop bound ary – the Pieniny Klippen Belt of the West ern Carpathians. In ter na - tional Jour nal of Earth Sci ences, 109: 1355–1376.
Pospíšil, L., Bezák, V., Nemèok, J., Feranec, J., Vass, D., Obernauer, D., 1989. The Muran tec tonic sys tem as ex am ple of hor i zon tal dis place ment in the West Carpathians (in Slo vak with Eng lish sum mary). Mineralia Slovaca, 21: 305–322.
Press, F., Siever, R., Grotzinger, J., Jor dan, T.H., 2004. Un der - stand ing Earth. 4th edi tion, W. H. Free man and Com pany, New York.
Ratschbacher, L., Frisch, W., Linzer, H.-G., 1991. Lat eral ex tru - sion in the East ern Alps, Part 2: struc tural anal y sis. Tec ton ics, 10: 257–271.
Ratschbacher, L., Frisch, W., Linzer, H.G., Sperner, B., Mes - chede, M., Decker, K., Nemèok, M., Nemèok, J., Grygar, R., 1993. The Pieniny Klippen Belt in the West ern Carpathians of north east ern Slovakia: struc tural ev i dence for transpression.
Tectonophysics, 228: 471–463.
Royden, L.H., Horváth, F., Burchfiel, B.C., 1982. Trans form fault - ing, ex ten sion and subduction in the Carpathian-Pannonian re - gion. GSA Bul le tin, 73: 717–725.
Ry³ko, W., Tomaœ, A., 2005. Base ment struc ture be low the West- Carpathian – East-Carpathian orog eny junc tion (east ern Po - land, north-east ern Slovakia and west ern Ukraine). Geolo gica Carpathica, 56: 29–40.
Sperner, B., Ratsbacher, L., Nemèok, M., 2002. In ter play be tween subduction re treat and lat eral ex tru sion: tec ton ics of the West - ern Carpathians. Tec ton ics, 21: 1051–1075.
Teïák, F., Kováèik, M., Pešková, I., Nagy, A., Buèek, S., Maglay, J., Vlaèiky, M., 2016. Geo log i cal Map of the Biela Orava Re - gion. ŠGÚDŠ, Bratislava.
Tikhonov, A., 1950. On de ter min ing elec tri cal char ac ter is tics of the deep lay ers of the earth’s crust (in Rus sian). Doklady Akademii Nauk SSSR,73: 295–297.
Tomek, È., Hall, J., 1993. Subducted con ti nen tal mar gin im aged in the Carpathians of Czecho slo va kia. Ge ol ogy, 21: 535–538.
Vanyan, L.L., 1997. Elec tro mag netic Soundings. Nauchnyy Mir, Mos cow.
Vozár, J., Šantavý, J. eds., 1999. At las of Deep Re flec tion Seis mic Pro files of the West ern Carpathians and its In ter pre ta tion. Geo - log i cal Sur vey of the Slo vak Re pub lic, Geocomplex, Inc., Bratislava.
Vozár, J., Bezák, V., Marko, F., 2021. An im proved view on crustal ar chi tec ture in cen tral Slovakia (West ern Carpathians) based on 3-D magnetotelluric model of 2T seis mic pro file. Geologica Carpathica, 71: 85–95.
Yeats, R., 2012. Ac tive Faults of the World. Cam bridge Uni ver sity Press.
