Durmitor Nappe, Southeastern Bosnia and Herzegovina)

GEOLOGIJA 54/1, 91–96, Ljubljana 2011

doi:10.5474/geologija.2011.007

Devonian conodonts from the Fo~a–Pra~a Paleozoic complex (Durmitor Nappe, southeastern Bosnia and Herzegovina)

Konodonti iz fo~ansko-pra~anskega paleozojskega kompleksa (durmitorski pokrov, jugovzhodna Bosna in Hercegovina)

Tea KOLAR-JURKOVŠEK1, Hazim HRVATOVI]2, Ferid SKOPLJAK3 & Bogdan JURKOVŠEK4

1, 4Geolo{ki zavod Slovenije, Dimi~eva ulica 14, SI-1000 Ljubljana; e-mail: tea.kolar�geo-zs.si, bogdan.jurkovsek�geo-zs.si, 2, 3Federalni zavod za geologiju, Ustani~ka 11, 71000 Sarajevo, e-mail: zgeolbih�bih.net.ba

Prejeto / Received 15. 3. 2011; Sprejeto / Accepted 13. 4. 2011

Key words: conodonts, Devonian, CR-17 borehole, Crna Rijeka, Bosnia and Herzegovina Klju~ne besede: konodonti, devon, vrtina CR-17, Crna rijeka, Bosna in Hercegovina

Abstract

Conodont study of the Crna Rijeka borehole CR-17, positioned in the frontal part of the Durmitor Nappe (Fo~a – Pra~a Paleozoic complex, SE Bosnia and Herzegovina) is presented. The obtained fauna indicates an Early-Middle Devonian age and due to poor preservation an identification at a generic level is possible only. The recovered conodont elements have a high Color Alteration Index (CAI = 6,5–7) indicating a degree of metamorphism corresponding to a temperature interval from 440 °C to 720 °C.

Izvle~ek

Predstavljene so konodontne raziskave vrtine Crna rijeka CR-17 v ~elnem delu pokrova Durmitor (paleozojski kompleks Fo~a – Pra~a, jugovzhodna Bosna in Hercegovina). Konodontna favna dokazuje spodnje-srednjo devon- sko starost, vendar je zaradi slabe stopnje ohranjenosti mogo~a le dolo~itev na stopnji rodov. Dobljeni konodontni elementi imajo visok barvni indeks (CA I = 6,5–7), ki kaže na stopnjo metamorfoze v temperaturnem intervalu od 440 °C do 720 °C.

Introduction

The goal of the CR-17 borehole (Fig. 1) was to acquire knowledge about the thickness of Devo- nian carbonate in the Crna Rijeka area of Bosnia and to recognize the geological characteristics of the area to support the project of the »Crna Rijeka Dam«, near Sarajevo (Ba{agi} & Skopljak, 2007). In this short report a documentation is presen ted of a conodont study carried out in Paleozoic strata of the Crna Rijeka CR-17 borehole, interval from 12 to 203 meters. The obtained conodont fauna indicates an Early-Middle Devonian age of the investigated samples present in some of the oldest strata in Bosnia and Herzegovina.

Geological setting

Geographically, the Crna Rijeka is located southeast of Sarajevo (Fig. 1). The area of Crna Rijeka is included in the Fo~a-Pra~a Paleozoic Fig. 1. Location map of the Crna Rijeka CR-17 borehole.

GEOLOGIJA_54_1_2011_internet.indd 91 30.6.2011 7:28:51 92 Tea KOLAR-JURKOVŠEK, Hazim HRVATOVI], Ferid SKOPLJAK & Bogdan JURKOVŠEK

complex of southeastern Bosnia and Herzegovina Lower and Middle Devonian limestone (Kosti}- and is positioned in the frontal part of the Durmi- Podgorska, 1958; Živanovi}, 1963; Panti}, 1963). tor Nappe, which tectonically overlies the Bosnia Some Paleozoic formations of the Fo~a area are Flysch Nappe (Fig. 2). of a presumed Devonian age. The thickness of the Southeastern Bosnia and Herzegovina compri Paleozoic formations attains up to 800 m in the ses the areas of Fo~a, Goražde and Pra~a. In the area (Buzaljko, 1971). between the Fo~a and Goražde areas the oldest Devonian formations are overlain by Early Paleozoic formations crop out in which Variscian Carboniferous flysch that is up to 1000 m thick. age structures are preserved. Thick-bedded lime- The flysch sediments contain ammonoids (go- stone occurs at Ustikolina with Late Silurian niatites, orthoceratides), mollusks, gastropods, conodonts Ozarkodina and Panderodus present brachiopods and corals. At Podkoran, an occur- (Buzaljko, 1971; Ramov{, 1989). rence of Early Carboniferous strata containing Lower Devonian strata are represented by dark goniatites was studied in detail by Kittl (1904). gray platy limestone with conodonts (Neoprionio- Based on the goniatite data, Frech (1906) and dus, Plectospathodus) and Upper Devonian lime- Schmidt (1924) supported a Visean age of some stone are marked by the presence of conodonts Paleozoic formations. Podgorska (1939) pub- (Palmatolepis), bryozoans and crinoids (Buzaljko, lished data on fauna from crinoidal limestone 1971; Ramov{, 1989). from the area of Pra~a. In the area of Klek on the easternmost slopes of Krsti} et al. (1988) gave explanation of the ori- Mt. Jahorina, “Orthoceras limestone” with Early gin for the Silurian and Devonian limestones in and Late Silurian conodonts and tentaculides are the Pra~a area of SE Bosnia considering them as present in the Pra~a thrust below Triassic forma- allochthonous clasts and olistoliths in the Lower tions (Kosti}-Podgorska, 1958). Here, a rich fauna Carboniferous „Culm“ flysch. Filipovi} & Jova of corals, stromatoporoids, hydrozoans, bryozo- novi} (1994) later provided new data for age and ans, brachiopods and crinoids was collected in characteristics of the same rocks in the Pra~a (SE

Fig. 2. Main structures of the Dinarides of Bosnia and Herzegovina (Hrvatovi}, 2006):  - CR-17 borehole. 1. Karst Nappe, 2. Una-Drežnica-Gacko Nappe, 3. Klju~-Radu{a Nappe, 4. Mid-Bosnian Schists Mts., 5. Bosnian Flysch Nappe, 6. Durmitor Nappe, 7. Ophiolite Nappe, 8. Golija Nappe, 9. Sana-Una Nappe, 10. Sava-Vardar Nappe.

GEOLOGIJA_54_1_2011_internet.indd 92 30.6.2011 7:28:53 Devonian conodonts from the Fo~a–Pra~a Paleozoic complex (Durmitor Nappe, southeastern Bosnia and Herzegovina) 93

Bosnia) and Vlasenica (NE Bosnia) areas, and conodont analyses. All of them are composite they interpreted them as Upper Carboniferous samples, covering over one meter of the most per- olistostromes connected with Asturian phase of spective divisions, i. e. in the less recrystallized Variscan orogenesis. and less tectonized parts of the drill hole. Three A break in sedimentation took place during the samples were composite samples embracing over Late Carboniferous and Early Permian. The Upper three to six meters of the borehole in order to ob- Permian is represented by reddish clastics overlain tain positive results. A standard technique for by Bellerophon limestone bearing gastropods (Bel- conodont extraction was applied by use of acetic lerophon) and calcareous algae (Gymnocodium). acid and then heavy liquid separation. The sam- The Bellerophon limestone was first recorded by ples were dissolved at the Geolo{ki zavod Sloveni- Bittner (1880) and documented later by Kittl je / Geological Survey of Slovenia. (1904) at Han Orahovica, Katzer (1926) at Zbi{}e Out of the 10 examined samples from the inve and Musi}i, and Kosti}-Podgorska (1958) at Vi stigated interval, six samples were productive for hor, Lunji and Razboji{te. In the area of Tjenti conodonts. However, conodont yields are rather {te, Cadet (1966) reported finding of brachiopods, low (Fig. 4). The obtained elements are largely mollusks and gastropods in dark gray thick bed- fragmented. An identification at a generic level ded limestone of Latest Permian age. In the area is possible only due to poor state of preservation. of the Kolina Valley, Fo~anska Jabuka and further The conodont elements recovered have a high towards Pra~a sideritic-ankeritic limestone were Color Alteration Index (CAI = 6.5–7) indicating a discovered with sulphides: pyrite, chalcopyrite, degree of metamorphism corresponding to a tem- arsenopyrite, galena and antimonite. Buzaljko perature interval from 440 °C to 720 °C (Rejebian (1971) made a detailed stratigraphic subdivision et al., 1987). of the Permian rocks of the Southeast Bosnia area Most of the forms are identerminable and only (Fig. 3). the elements of the two samples (CR 74-79 m and CR-17 193-195 m) enable comparison with Early– Conodont study Middle Devonian taxa.

The present study is based on collections from the borehole CR 17 of Crna Rijeka and made in Materials and methods 2006 (Kolar-Jurkov{ek & Jurkov{ek, 2006). Ten carbonate samples were collected, averaging ap- Photographs of all illustrated conodont ele- proximately 2 kg each. They were processed for ments presented herein were taken on the JSM-

M Age Lithology Environments Fossils <100 Bellerophon limestone, Shallow marine-lagoonal Bellerophon sp., P3 – sandstone, Archaeocidaris ladina, – gypsum, Gymnocodium sp. – redish schist, – siltstone Land? 850 – redish conglomerate, and quartz sandstone, Shallow marine to fluvial Naneionella, Mizzia cornuta, P1,2 – gray schist, marble, bedded limestone, Globivalvulina, Tubertina sp. – breccia 100 Sandstone, claystone, conglomerate, schist Trench Lepidodendron weltheimianum C3

Flysch: Trench Verneulites librovitchi C2 700 Flysch: Trench Lepidodendron lasseni, C1 Subgraywacke, sandstone, claystone, Glyphyoceras sphaericum, clayey-quartz-sericite schist, Aviculopecten pra~aensis, microconglomerate, massive limestone Cyathocarinia rasliana, Chonetes, Nereites 200 Bedded limestone Marine platform Hindeodella sp., D3 Palmatolepsis glabra pectinata, P. rhomboidea, Belodella triangularis 450 Massive reefal limestone Marine platform Favosites sp., D2 Polygnathus linguiformis

200 D Bedded limestone, layered schist Marine platform Neoprioniodus bicurvatus, 1 Plectospathodus, Panderodus unicostatus 100 S Massive limestone Marine platform Ozarkodina, 3 Panderodus

Fig. 3. Geological description of Paleozoic strata of SE Bosnia (Hrvatovi}, 2006; after Buzaljko 1971; Kulenovi}, 1985).

GEOLOGIJA_54_1_2011_internet.indd 93 30.6.2011 7:28:54 94 Tea KOLAR-JURKOVŠEK, Hazim HRVATOVI], Ferid SKOPLJAK & Bogdan JURKOVŠEK

5500 LV Scanning Electron Microscope of the Slo- faunas were reported from Jezera area near Jajce venian National Building and Civil Engineering in western Bosnia (Mudrenovi} et al. 1969) and Institute (ZAG Ljubljana). The conodont material from the platy limestones of SE Bosnia and Her- is stored in the micropaleontological collection of zegovina (Kulenovi}, 1983). All faunas are cha Geological Survey of Slovenia (Geolo{ki zavod racterized by the presence of Belodella. Near the Slovenije) under the inventory numbers GeoZS village of Kolakovi}i in SE Bosnia, Early Devo- 4072-4080, 4085. nian apparatuses of Belodella bosniensis Ramov{ and B. elegans Ramov{ were reconstructed that are accompanied by Ozarkodina remscheidensis Sample CR-17 74-79 m (GeoZS 4077) (Ziegler), Ozarkodina wurmi (Bischoff & Sanne- mann), and Icriodus steinachensis (Al Rawi) (Ra- A single element was recovered from this sam- mov{, 1989). ple. It is a spathognathodiform element (Pl. 1, Conodont faunas of Early Devonian age are Fig. 1) but the upper part of the denticles is broken also well documented from eastern Serbia and away but it appears to represent an Early-Middle are marked also by the presence of the genera Be- Devonian species of Ozarkodina or Pandorinel- lodella and Ozarkodina (Krsti} et al. 1970, 1995; lina (Robison, 1981; Suttner 2007). However, the Krsti} & Sudar, 1992, 1994). form also has certain similarities to Ozarkodina The studied conodonts are strongly affected by pandora Murphy, Matti & Walliser, an important metamorphism as indicated by a high CAI. Fur- Lockhovian datum (Murphy et al., 1981). thermore, most recovered conodonts are fragmented, corroded and recrystallized. This state of preservation is a result of the regional metamor- Sample CR-17 193-195 m (GeoZS 4080) phism and it markedly differs from the preservation of Triassic conodonts of Bosnia and Herzego- The sample yielded two fragments of coniform vina that show a lower CAI (Aljinovi} et al., 2006, elements with distinct longitudinal striation, yet 2011) and have lesser alteration. The comparison partly etched (Pl. 1, Fig. 2). The specimens are with observations made on conodonts of the Al marked by fine striation characteristic for Neo- banides is obvious (Schönlaub & Meço, 1986). panderodus that ranges from the Lower to the Middle Devonian (Robison, 1981). Nevertheless, the specimens can be compared with Belodella Conclusions striata Kozur, the only belodellid representative with fine striated ornamentation. This species was A brief geologic overview of southeastern Bosnia first described from the basal Pragian of the Up- and Herzegovina is presented and the results of a pony Mts. in Hungary (Kozur, 1984). micropaleontological study carried out in the Crna Rijeka are documented herein. Conodonts were recovered from the Paleozoic strata of the CR-17 borehole. The scant conodont fauna indicates an Remarks on the Early-Middle Devonian Early-Middle Devonian age of the studied inter- conodont faunas of Bosnia and Herzegovina val. The presence of conodonts in the tectonized carbonate facies is of significant importance for The first Lower Devonian conodont faunas in further study. The obtained results provide a re- Bosnia were described from the Dvor na Uni area liable basis for a detailed biostratigraphic study on the Croatian-Bosnian border (\ur|anovi}, aiming at a precise time assignment of the studied 1968, 1973). Later, a few localities with equivalent Devonian strata.

Depth (m) 12 68 74-79 136 144/2 164 180-185 188 193-195 203 Taxon

Ozarkodina sp. or - - 1 ------Pandorinellina sp.

Neopanderodus sp. ------2 - or Belodella sp.

conodont fragments 1 - - - - - 2 3 - 1

crinoid ossicles - - - - + - + - - -

Fig. 4. Numerical distribution of recovered conodonts and presence of crinoids in the studied samples of the Crna Rijeka CR-17 borehole.

GEOLOGIJA_54_1_2011_internet.indd 94 30.6.2011 7:28:54 Devonian conodonts from the Fo~a–Pra~a Paleozoic complex (Durmitor Nappe, southeastern Bosnia and Herzegovina) 95

Plate 1

Conodonts from the Crna Rijeka CR-17 borehole, Bosnia and Herzegovina, Early-Middle Devonian.

1 a–b Ozarkodina sp. or Pandorinellina sp. Sample CR-17 74-79 m (GeoZS 4077). a – lateral view, b – upper view.

2 a–b Neopanderodus sp. or Belodella sp. Sample CR-17 193-195 m (GeoZS 4080). a – b – lateral views.

Acknowledgements Bittner, A. 1880: Die Herzegovina und die östli- che Theile von Bosnien. Jb. Geol. R. A., 30/2: The authors gratefully acknowledge Merlynd Nestell 353–458. for reading the manuscript and making linguistic cor- Buzaljko, R. 1971: Geolo{ka gra|a podru~ja izme rections, Heinz Kozur and Mike Orchard made helpful |u Goražda i Rudog (jugoisto~na Bosna). Geol. and valuable comments on the conodont part. Reviews glasnik, 15: 69–88. of Sejfudin Vrabac and Milan Sudar are acknowledged. Cadet, J. 1966: Sur des niveaux permiens associes This study was partly carried out at the Geological Survey of Slovenia through the program P1-0011 fi- a des gypses on Bosnie meridionale (Yugoslavie). nancially supported by the Slovenian Research Agency. Seances de la Soc. geol. de France, Paris: 409 p. This study was also supported through the program \ur\anovi}, Ž. 1968: Konodonte donjeg devona i of bilateral cooperation in science and technology in donjeg karbona zapadno od Dvora na Uni (Hr- Slovenia-Bosnia and Herzegovina (2010-2011). Photo- vatska – Jugoslavija) / Conodonten des unter- graphs were taken by Mateja Golež and prepared by devons und Unterkarbons westlich von Dvor na Stanko Zakraj{ek. Uni (Kroatien-Jugoslawien). Geol. Vjesn., 21: 93–103. \ur\anovi}, Ž. 1973: O paleozoiku i triasu Med- References vednice (Zagreba~ke Gore) i podru~ja Dvora na Uni na temelju konodonta / About the Paleo- Aljinovi}, D., Hrvatovi}, H., Kolar-Jurkov{ek, zoic and the Triassic of Medvednica Mountain T. & Jurkov{ek, B. 2006: Early Triassic shelf and the area Dvor na Uni on the basis of cono- sedimentation of External Dinarides (Bosnia donts. Geol. Vjesn., 25: 29–49. and Herzegovina) and conodonts based bio Filipovi}, I. & Jovanovi}, D. 1994. Variscan olisto- stratigraphic revision. Norsk Geologisk Foreing stromes of Western Serbia and Eastern Bosnia. (NFG) Abstracts and Proceedings, 3, 39, Bo Geol. an. Balk. poluos., 58/2: 65–72. real Triassic 2006, Longyearbyen 16–19 August Frech, F. 1906: Das marine Karbon in Ungarn. 2006, Norway. Fold. Kozlony (Budapest) 36. Aljinovi}, D., Kolar-Jurkov{ek, T., Jurkov{ek, B. Hrvatovi}, H. 2006: Geological guidebook through & Hrvatovi}, H. 2011: Conodont dating of the Bosnia and Herzegovina. Geol. Glasnik, 28: Lower Triassic (Scythian) sedimentary rocks in 1–172. the External Dinarides (Croatia and Bosnia and Katzer, F. 1926: Geologija Bosne i Hercegovine. Herzegovina). Riv. Ital. Paleont. Stratigr., 117/1: Direkcija državnih rudarskih preduze}a u Sa- 135–148. rajevu. Ba{agi}, M. & Skopljak, F. 2007: Hidrogeolo{ka Kittl, E. 1904: Geologie der Umgebung von Sara- istraživanja za potrebe izrade glavnog projekta jevo. Jb. Geol. R. A., Wien 53: 515–748. vi{enamjenskog vodoprivrednog podsistema Kolar-Jurkov{ek, T. & Jurkov{ek, B. 2006: Izve Crna Rijeka – II faza. Institut za geologiju Gra|. {taj o konodontskim analizama »Projekt hi Fakulteta u Sarajevu. drogeolo{kih i hidrolo{kih istražnih radova i

GEOLOGIJA_54_1_2011_internet.indd 95 30.6.2011 7:28:55 96 Tea KOLAR-JURKOVŠEK, Hazim HRVATOVI], Ferid SKOPLJAK & Bogdan JURKOVŠEK

ispitivanja za potrebe izrade Glavnog projekta Murphy, M. A., Matti, J. C. & Walliser, O. H. 1981: vi{enamjenskog vodoprivrednog podsistema Biostratigraphy and evolution of the Ozarkodi- Crna Rijeka – II. Faza«. Arhiv Geolo{ki zavod na remscheidensis – Eognathodus sulcatus line- Slovenije: 1–3. age (Lower Devonian) in Germany and central Kosti}-Podgorska,V. 1958: Fauna i biostratigraf- Nevada. J. Paleont., 55/4: 747–772. ski odnosi paleozojskih tvorevina u okolini Panti}, S. 1963: Rezultati mikropaleontolo{kih Pra~e. Geol. glasnik, 4: 1–210. ispitivanja uzoraka iz {ire okoline Pra~e, FSD Kozur, H. 1984: Preliminary report about the Geol. zavoda Srbije, Beograd. Silurian to Middle Devonian sequences near Podgorska, V. 1939: Novi prilozi za poznavanje Nekézseny (southernmost Uppony Mts., north- paleozoika u okolini Pra~e nedaleko od Sara- ern Hungary). Geol. Paläont. Mitt. Innsbruck, jeva. Geol. Anali. Balk. Pol., Beograd: 16 p. 13/7: 149–176. Ramov{, A. 1989: Two new Belodella apparatuses Krsti}, B., Filipovi}, I. & Maslarevi}, Lj. 1988: (Conodonta) from the Lower Devonian of Bo Palaeozoic olistostromes of Pra~a area, SE Bo snia, Yugoslavia. Geol. Palaeontol., 23: 39–51. snia. Geol. an. Balk. poluos., 51: 223–229. Rejebian, V.A., Harris, A.G. & Huebner, J. S. 1987: Krsti}, B., Spasov, H., Stojanovi}-Kuzenko, S. & Conodont color alteration and textural altera- Paji}, V. 1970: Prilog poznavanju donjeg i sred- tion: An index to regional metamorphism, con- njeg devona u isto~noj Srbiji. Vesnik Zavoda tact metamorphism and hydrothermal altera- geol. geofiz. istraž. 28, Ser. A: 307–326. tion. Geol. Soc. Am. Bull., 99: 471–497. Krsti}, B. & Sudar, M. 1992: Paleozojski kono- Robison, R. A. (Ed.) 1981: Conodonta. In: Treatise donti isto~ne Srbije, Jugoslavija (V). Ann. Geol. on Invertebrate Paleontology. Part W. Miscel- Penins. Balk., 56/1: 185–210. lanea, Supplement 2, W202 pp., 119 fig., Univ. Krsti}, B. & Sudar, M. 1994: Paleozojski kono- Kansas & Geol. Soc. Am. Press, Lawrence. donti isto~ne Srbije, Jugoslavija (VII). Ann. Schmidt, H. 1924: Die Carbonischen Goniatiten Geol. Penins. Balk., 58/1: 139–148. Deutschland. Jahrb. Preuss. Geol. Landesanst, Krsti}, B., Sudar, M. & Maslarevi}, L. 1995: Pa Berlin: 45 p. leozojski konodonti isto~ne Srbije, Jugoslavi- Schönlaub, H. P. & Meço, S. 1986: Lower Paleo- ja. VIII. Alohtoni silurski, devonski i donjo zoic Conodonts from Albania. Jb. Geol. B.A., karbonski kre~njaci u paleozojskom fli{u isto~ne 128/3+4: 439–447. Srbije. Ann. Geol. Penins. Balk., 59/1: 149–163. Suttner, T. J. 2007: Conodont Stratigraphy, Fa- Kulenovi}, E. 1983: Paleozoik u Bosni i Hercego- cies-Related Distribution Patterns and Stable vini / The Paleozoic era in Bosnia and Herze- Isotopes (Carbon and Oxygen) of the Upper- govina. Akad. Nauka Umjet. BiH. Pos. izd. 59, most Silurian to Lower Devonian Seewarte Odjelj. Tehn. Nauka, 12: 89–107. Section (Carnic Alps, Carinthia, Austria). Abh. Mudrenovi}, V., Stojanovi}-Kuzenko, S. & Paji}, V. Geol. B.A., Band, 59: 1–111. 1969: Razvoj silura i devona u podru~ju Jezera Živanovi}, M. 1963: Zna~aj nalaska Karpinskia kod Jajca (Z. Bosna). III simpozijum Dinarske consuelo geyeri Gortani na Kleku (jugoisto~na asocijacije, Institut za geolo{ka istraživanja Za- Bosna). Geol. Glasnik, 8: 41–45. greb: 135–146.

GEOLOGIJA_54_1_2011_internet.indd 96 30.6.2011 7:28:55