GEOWGICA BALCANICA, 26. 2, Soft&, Jun. 1996, p. 3-10

Geological Heritage of the Balkan Peninsula: Geological setting (an overview)

Ivan S. Zagorchev

Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, build. 24, 1113 Sofia

Hs. 3azop'U!6 - reoAOZU'leCJCoe HaCAedcmso EaAKaHc­ Abstract. The Balkan Peninsula represents a region of KOzO n011yocmp06a: zeOAOZU'U!CKtlJf paMKa (0030p).lian­ particularly complex geological composition and structure IaHCKRI oonyOCTPOB xaparrepH3yeTCI ~pe3B~~alao that is situated within the boundary between the Eurasian cno:aHWMR reonOrH'IeCDIM COCTaBOM B CTPOeHBeM, ~TO and African plates where the Tethyan Ocean has been o6ycnoBneao ero nono:ateaaeM aa CThfl(e MeQy EBpa- consummed in Alpine times. The geological structure 3Bica:oii a A.Ppaa:aacJtoii DJlhlTaMH r.Ae B am.DBAca:oM represents the setting of many geosites of national, regional BpeMeHB 6w1 a:oacyMMHPoBaa TeTacltBA oa:eaa. Cno:at­ or world-wide importance. au reonorH~eca:u CTPYITYPa coCTaBnleT P&MitY MHO­ rex 3neMeHTOB reonora~eca:oro aacne.ACTBa aa~ao­ aan&soro, perHoaan&aoro H MBpOBoro 3Ha~eau.

Zagorchev, I. 1996. Geological Heritage of the Balkan Peninsula: Geological setting (an overview). - Geologica Bale., 26, 2; 3-10. Key words: geological heritage; Balkan Peninsula; geological setting

Introduction Heritage of : National Strategy and Sites of Special Scientific Importance" of the National The First Subregional Meeting "Conservation of Fund "Scientific Research" of Bulgaria. the Geological Heritage in South-East Europe" (6 - 12 May 1995; Bulgaria) outlined the Geological Heritage possibilities for establishment of a subregional Balkan Geological Heritage List, as an integral In the broadest sense, the Geological Heritage part of the European and World Geological of a natural or political region consists (Za­ Heritage Lists. Several contributions have been gorchev, Tzankov, 1996) of its whole geological dedicated to particular geosites or geological wealth, as: 1) mineral occurrences (mineralogical areas of the Balkan Peninsula that represent a features, mineral ore and non-metallic deposits); precious geological heritage of our countries. 2) water sources (mineral, karst, etc.); 3) rocks They are published in the present special issue (petrologic features); 4) fossils; 5) stratigraphic of Geologica Balcanica in accordance with the sections and other stratigraphic features; 6) decisions of the Editorial Board and of the First structural-geological features; 7) complex Subregional Meeting. geological sites; 8) old and/or abandoned The present paper aims to give some essential quarries and mines; 9) unique objects and sites; general information about the most typical 10) geomorphic features; 11) coal and hydro­ geological features of the Balkan Peninsula carbon deposits; 12) geological information. relevant to the evaluation of our geological According to the classification of the IUGS heritage. The author is indebted to Dr W. Global Geosite Working Group (Anon., 1995), Wimbledon who stimulated this paper as well the geosites that are elements of the World as to many colleagues who supplied precious Geological Heritage belong to the following information and advice. The paper is written Earth Science Categories: A. Palaeobiology; B. within the frame of the project "The Geological Geomorphic; C. Palaeoenvironmental; D.

3 Igneous, metamorphic & sedimentary; E. (north-vergent Carpatho-Balkanides and south­ Stratigraphic; F. Mineralogic; G. Structural; H. vergent Dinarides - Hellenides) divided Economic; I. Historic; J. Relationships: tectonic (according to different viewpoints exposed) by plates; K.. Astroblemes; L. Continental/Oceanic a central or median massif (Rhodope Mass, global scale features; M. Submarine. Geosites Thracian Massif, Rhodope Massif, etc.) or are also regarded as being important for the central (third) branch of the orogen. The characterization of: I. major stages of Earth structure that divided the two branches was history; II. ongoing geological processes; Ill. sought either in one of the massifs (Serbo­ geomorphic, physiographic features. The Macedonian, Rhodope, Thracian) or in a suture charact~ristics of the geological sites in respect (Vardar Zone, Maritsa suture, K.raishtid-Vardar to their interest for the specialists and the general Lineament). public favour a most convenient classification The modern tectonic concept is based upon that defines three large groups: geological sites the plate tectonics ideas about the evolution of of economic, commercial or utilitarian value the Tethyan Ocean and of several microplates (GSECV), geotopes (geosites) of special situated between the Eurasian and African scientific importance (GSSSI) and geotopes plates. Drastic changes within this evolution (geosites) of aesthetic value (GAY). The present occurred during several important compressive paper is not concerned with the first category phases in Late Triassic, Late Jurassic, Mid­ because it is the subject of metallogenetic, Cretaceous, Late Cretaceous, Mid-Eocene, latest economic, hydrogeological and other research. Eocene and earliest Miocene times. Relics of The geological heritage in the narrower sense is Paleozoic and pre-Paleozoic rocks, structures concerned with geological sites remarkable with and are reworked and incorporated into their aesthetic, educational and scientific value. the Alpine structures, and tectonic llnits from Their evaluation is based upon aesthetic value, the older orogens are welded into the younger rarity or uniqueness, access for scientific and ones as an intricate jigsaw puzzle. The picture educational purpose. The geological setting of is even more complicated in Neogene and the Balkan Peninsula is considered here in Quaternary times when prevailing vertical respect of such features of the geological movements in conditions of generalized exten­ heritage. sion led to block rotations and formation of a The geological sciences study the present 3D neotectonic block pattern. Controversial recon­ structure of the Earth's crust as a result of the structions are often based more on fashionable long evolution through geologic time. Although ideas than on real evidence. Therefore, key each geological site is in some sense a unique sections and outcrops may be of paramount natural feature, many sites contain common or importance for confirming or rejecting some of comparable features or elements of similarity. the hypotheses, thus representing most valuable Only few of the geosites may be considered as geological heritage. being of outstanding value as the finest The superposition of Alpine orogenic (fold specimens that demonstrate the typical features and thrust) structures issued from different, of their kind. Few others are unique phenomena mostly continental and epicontinental marine that have no similar sites all over the world. This basins resulted in a complicated pattern further paper aims to outline mostly such geological exhumed and modelled by neotectonic move­ features of the Balkan Peninsula that bear the ments and erosion. Rock complexes of different marks of rarity or uniqueness, and to look for age occur in the Alpine tectonic units, covering geosites that can be regarded as the finest almost the full range from the Precambrian examples of such features. (Middle Riphean or even older) and Paleozoic to the Quaternary. Several different pre-Alpine section types clearly belong to different pre­ Alpine (Alpidic) structure Hercynian and Hercynian environments, and are covered with unconformable depositional The classical concept about the Alpine structure contact by different Hercynian molasse deposits of the Balkan Peninsula was conceived within of Carboniferous or Permian age, and/or directly the classical frame of the geosynclinal theory in by Alpine sedimentary and volcanic complexes. the nineteenth century by E. Suess, J. Cvijic and The most important pre-Alpine complexes are: other scientists, and further elaborated in the (i) Precambrian amphibolite-facies metamorphic first half of the twentieth century by L. Kober, complexes (Ograzhdenian and Rhodopian F. Kossmat, V. Petkovic, S. Boncev, E. Boncev, Supergroups in Bulgaria, and their equivalents J. Brunn up to the "Geosynclines" of J. Aubouin. in the other Balkan countries - e.g., Ko­ It recognized the existence (e.g., Mabel' ed., zhoukharov, 1986; Mountrakis, 1986; Zoubek, 1974) of two branches of the Alpine orogen ed., 1988; Papanikolaou, 1989); (ii) Vendian -

4 Cambrian greenschist-facies metamorphic rocks 1982; Papanikolaou, 1983, 1984; Arsovski, tb.at primarily belonged either to ocean Dumurdzhanov, 1984; JacoBshagen, 1986; environments or to island-arc associations with Mountrakis et al., 1987; Boyanov et al., 1989). abundant diabases (e.g., Haydoutov, 1989); (iii) These tectonic regions are (from the North low-grade to greenschist-facies terrigenous to the South): (i) Moesian region (platform); (ii) formations (with some carbonates and silicites) Carpathian ; (iii) Balkan (Stara of Ordovician to Late Devonian age (e.g., Yanev, Planina) Mountain range; (iv) Srednogorie 1994). All three types of pre-Alpine complexes region (including the Maritsa valley); (v) are intruded by Hercynian (and in some cases, Macedonian - Rhodope (Morava-Rhodope) even older) granitoid plutons. region with the Rhodope, Strouma, and Morava The geological structure of the Balkan (=Serbo-Macedonian) subregions; (vi) Vardar Peninsula may be considered within several main region (zone); (vii) Dinaride-Albanide-Hellenide regions (Fig. 1) that possess specific tectonic and region with the Pelagonian subregion; (viii) neotectonic features thus representing also Ionian region. The Alpine (s.l.) tectonic units morphostructural zones (Boncev, 1971, 1986; resulted from the subsequent superposition of Mabel', ed., 1974; Petkovic, 1977; Andelkovic, Alpine orogens of Late Jurassic, Mid-

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Fig. 1. Tectonic sketch for the Alpine structure of the Balkan Peninsula (after data of the references). Abbreviations of tectonic zones and/or units: Ate- Attica; B- Budva; EBik- East Balkan (Louda-.Kamcbiya); ERhd-East-Rhodope; F1 - Flambouro; Frg - Fruslca-gora; IBD - East Bosnian - Durmitor; Mn - Mani; Ogr - Ograzhden; Olm - Olympos; NDbr - North Dobrudzba (Dobrogea); Par- Pamas; Png- Pangaion; Sa - Salcar; St - Strandzha; Str­ Strouma; Tri- Tripolitza; Vdr- Vertiscos + K.erdilia; WBlk- West Ba1kan; 5 Cretaceous, Late Cretaceous and Paleogene age zone of the Stara-Planina belt, the Geticum and within the southern margin of the , the Srednogorie zone (superunit), and the the Tethyan Ocean and the northern margin of Suprageticum and the external part of the the African (Apulian) plate. Fragments from Moravides. older, Hercynian and pre-Hercynian tectonic The Stara-Planina (Balkan) fold-thrust belt units are exposed within the cores of positive (Balkanides) has been essentially formed in Alpine fold structures or within some of the Paleogene times although it contains rock Alpine thrust sheets. formations within the whole range from the Mesozoic sedimentary formations are of Vendian - Cambrian to the Paleo­ utmost importance for the Moesian region, gene. Fragments of the Hercynian, Late Triassic Balkanide fold-thrust belt, and especially, for (embryonic), Mid-Cretaceous and Late the Dinaride-Albanide-Hellenide fold-thrust Cretaceous orogens are incorporated in this belt, and have a limited occurrence in the structure. Considerable differences are found Srednogorie region and the Strouma Superunit. between the Western + Central Balkan Most of the formations in the Balkanide belt Mountains and the Eastern (East-Balkan, or are of a shallow-basin (carbonate or terrigenous) Louda-Kamchiya Superunit), specially marine type, with Upper Jurassic - Lower concerning the Triassic and Jurassic sequences Cretaceous flysch formed in the Nish-Troyan (Tethyan type similar to that in northern trough, and Upper Cretaceous tephrogenic Dobrogea, and preserved in allochthonous flysch formed in the Srednogorie zone. The most sheets within the East-Balkan Superunit; peri­ important unconformities occur at the base of Tethyan type in the Western and Central Balkan) transgressive formations of Lower or Middle and the broad development of olistostrome Jurassic (over Upper Triassic or older formations of Cretaceous and Paleogene age in formations), Upper Cretaceous, Paleogene and the East . Neogene age. Within the Dinaride-Albanide­ The Srednogorie zone (superunit) was formed Hellenide belt, the different sedimentation zones mainly in Late Cretaceous times as a complex within the former Tethyan Ocean are followed volcanic island arc (mainly of andesitic as "isopic zones" over considerable distances. composition) with marine troughs over a Relics of the Tethyan are complex basement. They were later involved in represented by masses of considerable the north-.vergent thrusting over the Stara extent and a Triassic age usually covered by Planina belt. Deeply eroded parts of the Jurassic and Cretaceous terrigenous (including basement (Precambrian Ograzhdenian Super­ flysch-like) and carbonate formations. In other group intruded by numerous Hercynian gra­ isopic zones, the marine (often pelagic) nitoid plutons) occur in some of the most sedimentary formations cover without any uplifted areas. The relics of Late Jurassic? and significant breaks the whole Alpine sedimen­ Mid-Cretaceous tectonics in the Sakar Superunit tation range from the Permian (or Lower (the only one with proven amphibolite-facies Triassic) to the Eocene or Oligocene. The isopic metamorphism of Jurassic age superimposed zones of the External Dinarides, Albanides and both over Triassic sedimentary formations and Hellenides (Ionian Zone included) are Precambrian metamorphics) and the Strandzha characterized by shelf carbonate formations Superunit are of particular interest. (carbonate platform) that correspond to the The Morava-Rhodope region was in Late African margin. Cretaceous times a part of a second arc (hence, The Moesian region is the most stable part of of a thickened crust) situated closer to the the southern Eurasian margin in Alpine times subduction zone in the eastern board of the (Moesian platform). The Paleozoic basement is Tethyan Vardar ocean. It consists of several covered by an Alpine section with several tectonic units and superunits assembled in Mid­ unconformities and sedimentation breaks in Late Cretaceous time: the allochthonous Morava and Triassic - Early Jurassic, Early - Late Cre­ East-Rhodope superunits, the allochthonous to taceous and Paleogene times. parautochthonous Ograzhden unit, the para­ The Carpathian thrust belt is a complex utochthonous Strouma and -Pangaion orogen of Paleogene - Neogene age and superunits, and the Central-Rhodope superunit. considerable eastward thrusting (Sandulescu et Precambrian and Paleozoic metamorphic rocks al. in Mabel', ed., 1974).1t consists of the Eastern are abundant, and they occur in differently Carpathians (Moldavides and Dacides) covered preserved sections iri the individualized Alpine by the internal zones (from bottom to top) of tectonic units. Horizontal movements with Danubicum, Geticum and Suprageticum. different vergence (toNE, SW, South, etc.) acted Correlations along the plate margin are sought in alternation during the different compression between the Danubicum and the Fore-Balkan phases. The structure was complicated during 6 predominantly vertical block movements in Balkan Peninsula has a great potential of geosites Paleogene times when grabens and large that can be of major importance for un­ depressions were filled in with thick sedimentary derstanding the geologic history of the Earth, and volcanic (intermediate to acid composition, and that may represent unique geological with rare basic members) formations, and features worth inclusion in the World Geological Paleogene granitoid and monzonite plutons Heritage List. formed at deeper crustal levels being later (in Neogene and Quaternary times) exhumed by erosion. The huge amount of magma has Neotectonic structure produced a considerable thermal effect over the metamorphic and granttic basement. The neotectonic structure of the Balkan Pe­ The Vardar Zone (Sumadides) consists of ninsula is formed mostly after the last important several units of different composition and age, compressive phase in the beginning of Miocene and includes typical oceanic crust. Thus, it is time, and after the following peneplanation in considered as a suture zone formed at the place Early and most of Middle Miocene times. Fault of the closed Vardar Ocean. However, it has also movements became most active in late Middle a complex structure, and its separate tectonic Miocene and in Late Miocene times, and they units are also characterized by diverse formed a complex mosaic horst-and-graben composition and geologic history. Blocks of pre­ pattern. It is inherited to a great extent by the Alpine rocks are also incorporated in the zone. present-day relief that varies from the sea level The age of the ophiolites is clearly pre-Late to altitudes of more than 2000 m, reaching up Jurassic, and within the eastern (Peonia) unit to more of 2900 m (Rila, Olympos and Pirin basic rocks and pillow-lavas are covered by Mountains). formations of Jurassic and Cretaceous age. The The central parts of the Balkan Peninsula may Alpine formations possess different facies be characterized as a Central-Balkan neotec­ characteristics across the longitudinal subzones tonic region (Zagorchev, 1992) with a core of (isopic zones) defined (e.g., Andelkovic, 1982; thickened continental crust and positive tenden­ Papanikolaou, 1983, 1989; Jacobshagen, 1986; cies, gradually thinning towards the surrounding Mountrakis et al., 1987; Dimitrijevic, 1992) as Neogene and/or modem Precarpathian, Euxi­ Inner (eastern) Vardar subzone (Circum­ nian (), Aegean (representing an Rhodope belt), Central Vardar subzone (Peonia) independent Aegean neotectonic region), and External (western) Vardar subzone (Paikon). Adriatic (Ionian) and Pannonian marine basins. The Pelagonian Zone (Massif) is characte­ The following principal neotectonic subregions rized (Mountrakis, 1986; Papanikolaou and can be distinguished (from the North to the Stojanov in Zoubek, ed., 1988) by a complex South): (i) Lower Danube plain (depression); (ii) composition of pre-Alpine and Alpine for­ Carpathian linear positive morphostructure; (iii) mations (including Precambrian metamorphics Stara Planina linear positive (horst) morpho­ and Carboniferous granites) and a complex structure; (iv) Sub-Balkan graben complex and structure dominated by Alpine thrusting. Its Sredna Gora neotectonic swell; (v) Maritsa possible northern prolongation is represented by complex depression (graben system); (vi) the Drina-Ivanjica element (Dimitrijevic, 1992) Rhodope complex horst system; (vii) Strouma built up of Paleozoic basement and a Triassic complex graben system; (viii) Serbo-Macedonian carbonate platform. swell and complex horst; (ix) Vardar (Axios) Dinarides (on the North) and Albanides and complex graben system; (x) Dinaric-Hellenic Hellenides (to the South) represent a complex complex positive (horst) linear morphostructure. pile of southwest-vergent nappes formed at the The Rhodope complex horst system coincides expense of an internal (eastern) carbonate with the area of the thickest crust on the Balkan platform, a central ocean basin with pelagic car­ Peninsula thus representing its natural core. The bonates and radiolarites (Pindos-Olonos Zone) thickness of the crust is gradually decreasing and an external (western) carbonate platform. from 50-55 km in the westernmost parts, to 35 - The oldest rocks present are of Permian age, 40 km in the east. Based on the altitude of the and sedimentation has proceeded almost denudation surfaces, and mainly, of the initial without interruptions up to the Oligocene times. peneplain (orthoplain) with Early-Middle This complex structure was thrust in Paleogene Miocene age, the Rhodope area is a complex times to the South-West, over the Periadriatic neotectonic swell composed by the Rila dome, margin (Ionian Zone) of the Apulian (African) West-Rhodope swell, East-Rhodope swell, and plate. the Pirin neotectonic horst that is also the eastern It is evident that the present complex Alpine uplift towards the Strouma rift. The internal and pre-Alpine structure and composition of the structure of the Rhodope complex swell is 7 complicated by a number of second-order horsts times with spectacular and devastating and grabens. earthquakes exhibit in Peloponnessos striking The Belasitsa, Ograzhden and horsts examples of all combinations of normal faulting are a part of another large neotectonic swell with formation of different (and on different (Serbo-Macedonian swell) that is dominated by scale) tectonic blocks, sedimentary basins, neotectonic subsidence, and the formation of interrelations of tectonics, sedimentation, etc. the Strouma and Vardar rifts in its eastern and Tectonic and volcanic processes in historic times western boards. The Strouma rift, formed along are most typical for some of the islands that the NNW -SSE-striking Strouma lineament, is represent a part' of the Aegean volcanic arc. characterized by the greatest vertical neotectonic amplitudes: up to 3.5 km in the eastern board of the graben (with more than 1.6 km Geological Heritage of the Balkan of Neogene sediments), and with I;IlOre than 3.5 Peninsula in the light of its geological km of Neogene sediments in the Serres graben setting in Northern Greece. The Vardar rift shows an even greater neotectonic activization, with older The Geological Heritage of the Balkan Peninsula (Lower-Middle Miocene) grabens and deve­ is an integral part of the World Geological lopment of Neogene volcanic activity. Heritage. The particular features of its geological Another (Maritsa) complex graben system is setting are: (i) presence of old (Precambrian and situated north of the Rhodope along the WNW­ Paleozoic) crustal fragments incorporated in the ESE Maritsa lineament. It consists of the Sofia Alpine orogens, and reworked to a different graben and the Upper Thrace depression, and a degree by the Alpine tectonic and metamorphic number of small grabens within the Ihtiman and processes; (ii) presence of several Alpine tectonic Sushtinska Sredna Gora horsts. The latter microplates that developed different types of represents also a neotectonic swell with sedimentation environments during their asymmetrical grabens formed in its southern interaction throughout the Mesozoic and (Panagyurishte, Strelcha) and northern (Sub­ Cenozoic times, and were transformed by the Balkan graben system) boards. The Sofia graben tectonic processes (also differing in intensity and is a part both of the Sub-Balkan and of the type) to tectonic units of different character; (iii) Maritsa graben system. variable neotectonic evolution due to variable The Stara Planina (Balkan) linear horst inheritance, and interaction of recent plate morphostructure is the backbone of the Balkan motions, internal inhomogeneities and block Peninsula. The greatest neotectonic amplitude adjustments in conditions of dominant extension (about 2 km) is recorded on its southern board, and differentiated vertical block and swell along the Sub-Balkan fault that represents the movements. These major features are exhibited boundary with the Sub-Balkan complex graben. in different manners in the tectonic regions The northern board of the Stara Planina outlined, and create a variety of geological site~ morphostructure is gradually lowering towards and phenomena that certainly should be the Lower Danube plain (depression). The latter regarded as a precious part of the World was covered partly in Neogene time by the Heritage. We shall discuss hereafter only some Precarpathian marine basin. of the most striking examples. The neotectonic edifice of the Dinaric­ The fragments of pre-Phanerozoic crust (and Hellenic Mountains is a complex assemblage of the Rhodope massif in particular) contain neotectonic positive linear morphostructures typical geosites that exhibit striking examples of (horst mountain ranges) with longitudinal superposition of tectonic, metamorphic and depressions and longitudinal, transversal and igneous processes and events throughout a oblique grabens. Karst phenomena are wide­ complex geologic history. Many controversies spread in the relics of former Alpine carbonate exist (e.g., Kozhoukharov, 1986; Jacobshagen, platforms. 1986; Mountrakis, 1986; Aleksic, Dimitriadis, Special interest is focused on the extensional Kalenic, Kozhoukharov, Kozhoukharova, processes within the Aegean neotectonic region. Panagopoulos, Papanikolaou, Stojanov, Zagor­ It is characterized mostly by a thinned chev in Zoubek, ed., 1988; Papanikolaou, 1984, continental crust, and by generalized neotectonic 1989; Burg et al., 1990; Zagorchev, 1994, 1995) extension (according some scientists, with a as far as dating of the principal geologic events factor reaching 2.5-3) and the opening of the is concerned, and they are mainly due to the Aegean basin. Most active neotectonic processes variable intensity of reworking by Alpine (research by I. Mariolakos and co-workers; see processes. The geological environments in such Mariolakos, Papanikolaou, 1985) throughout fragments are clearly different from the classical Neogene and Quaternary (Pleistocene to Recent) localities of the Alps where the intensity of

8 reworking makes the research on the pre-Alpine fauna in amphibolite-facies metamorphics geologic history almost impossible. The relations (Sakar Mountain) are some of the most already observed in the Rhodope massif, outstanding examples of that kind. Alpine Sushtinska Sredna Gora and Sakar units in the igneous rocks and complexes (Dabovski et al., Srednogorie Superunit, Ograzhden Unit (Serbo­ 1991) often exhibit features of international Macedonian massif), Pelagonian massif, etc. importance. require to establish and protect geological sites Rare tectonic phenomena as antiformal with special scientific importance as sections, synclines, some rare thrust structures (see quarries, etc. with particularly well exposed Zagorchev, 1996, same volume), relations interrelations between different geological bodies between different fault and block structures in and processes, and to found geological polygons southern Peloponnessos (studies of I. Mariolakos in order to facilitate the study of these bodies and co-workers; e.g., Mariolakos, Papanikolaou, and processes with different methods and by 1985), low-angle normal faults (Zagorchev, 1995) different scientific teams. and related structures should be also considered The Paleozoic formations and structures are as SSSI. Complex tectonic structures and regions most interesting in respect of the identification exhibit real tectonic and neotectonic panoramas of different Gondwana and peri-Gondwanian (Zagorchev, Tzankov, 1996). fragments and environments, and of the The complex and varied geological com­ reconstruction of the various parts of the position and structure of the Balkan Peninsula Hercynian orogen (e.g., Haydoutov, 1989; favoured the formation of various mineral Papanikolaou, 1989; Yanev, 1993). Paleozoic deposits and findings, some of them being of and pre-Paleozoic ophiolites, typical sections particular importance for the geological (stratotypes of Paleozoic formations), igneous sciences. Some abandoned mines and quarries rock associations and bodies with their could be managed as underground or open-air interrelations yield nice exposures that should museums, and would have a major educational be protected and managed for observation, and scientific value. educ~tion and research purposes. Most of the protected natural sites represent Special attention should be given also to the products of Neogene and Quaternary erosion. ophiolite complexes of different age: Precam­ Some of them are of outstanding beauty. Caves, brian (Kozhoukharova in Zoubek, ed., 1988), gorges, cliffs, rock bridges, "pyramids", glacial Paleozoic (Haydoutov, 1989) and Mesozoic valleys and morraines, etc. are abundant on the (Ivanov et al., 1987). Some of the ultrabasic Balkan Peninsula but some of them are really bodies underwent several phases of meta­ special, as, e.g., the Vicos Gorge (Greece), morphism in different times, high-pressure Markovi kouli (Macedonia), Devil's Chimneys metamorphism (eclogites) included. Geosites (), Belogradchik cliffs (Bulgaria), and exhibiting interrelations between the ophiolites many others. Localities as the Madara Cliffs and and different pre-dating, co-eval and post-dating Melnik Pyramids (Bulgaria), Meteora and the rock complexes are of particular importance for Acropolis in Athens (Greece) and other geosites the international geological community. combine features of geological importance with Stratotypes of formal lithostratigraphic units natural beauty and great archaeological and should be placed under protection as geotopes historical value. In other cases, important of regional importance. Some of the most geosites should be considered within the important sections (Mesozoic and Paleogene in framework of important national parks or the Pindos Mountains; Permian and Triassic on reserves (Zagorchev, 1995) famous with their the islands of Chios and Salamina; Triassic and biodiversity and numerous endemic and/or rare Jurassic sections in Northern Dobrogea; Jurassic plant and animal species. sections of Tethyan and Peri-Tethyan types) should be considered for inclusion in the regional or world heritage lists. Typical sites of unconformities, fossil-rich localities, etc. are also References and selected bibliography of regional or world-wide importance. Tertiary Anon. (lUGS Global Geosite Working Group). 1995./UGS petrified forests (Lesvos, Eastern Rhodope GEOSITES. Database on Geological Sites. Database Mountains), the unique phenomenon of form. "Pobitite kamuni" near Varna (natural sandy­ Andelkovic, M. 1982. Geology of . Tectonics. calcareous columns formed among sandstone University of , Beograd; 692 p. (in Serbian). Arsovski, M., Dumurzhanov, N. 1984. Recent findings of of Eocene age by a mechanism, that is subject the structure of Pelagonian horst-anticlinorium and its of more than hundred publications and tens of relation with Rhodopean and Serbo-Macedonian hypotheses) and the localities with Triassic fossil masses. - Geologica Macedonica, 1, 1.

2 9 Boncev, E. 1971. Problems of Bulgarian Geotectonics. Mountrakis, D. 1986. The Pelagonian Zone in Greece: a Tebnika, Sofia (in Bulgarian). polyphase-deformed fragment of the Cimmerian Boncev, E. 1986. The Ballcanides. Geotectonic position and continent and its role in the geotectonic evolution of development. Publishing House of the Bulgarian the Eastern Mediterranean. -Journal of Geology, 94; Academy of Sciences, Sofia, 273 pp (in Bulgarian). 335-347. Bornovas, J., Rondogianni-Tsiambaou, lb. 1983. Mountrakis, D., Kilias, A., Pavlides, S., Patras, D., Geological map of Greece 1:5()()()()(). lOME, A-thens. Spyropoulos, N. 1987. Structural geology of the Internal Boyanov, I., Dabovski, C., Gocev, P., Harkovska, A., Hellenides and their role to the geotectonic evolution Kostadinov, V., Tzankov, Tz., Zagor~. I. 1989. A of the Eastern Mediterranean. - Acta Naturalia de new view of the Alpine tectonic evolution of Bulgaria. "L 'Ateneo Parmense", 23, 4; 147-161. -Geologica Rhodopica, 1; 107-121. Papanikolaou, D. 1983. Geotectonic map of Greece Burg, J.-P., Ivanov, Z., Ricou, L.-E., Dimov, D., Klain, L. 1:25()()()()(). University of Athens. 1990. Implications of shear-sense criteria for the Papanikolaou, D. 1984. The three metamorphic belts of tectonic evolution of the Central Rbodope Massif. - the Hellenides: a review and a kinematic interpretation. Geology, 18; 451-454. -Spec. PubL GeoL Soc. London, 17; 551-561. Dabovski, C., Harkovska, A., Kamenov, B., Mavroudchiev, Papanikolaou, D. 1989. Are the Medial Crystalline Massifs B., Stanisbeva-Vassileva, G., Yanev, Y. 1991. A of the Eastern Mediterranean drifted Gondwanian geodynamic model of the Alpine magmatism in fragments? - GeoL Soc. Greece, Spec. PubL 1; 63-90. Bulgaria. - Geologica Balcanica, 21, 4; 3-16. Petkovic, K. 1977. Geology of Serbia. Volumes I- VIIJ. Dimitrijevic, M. 1992. Geological atlas ofSerbia 1: 2()()()()(X). University of Belgrade, Belgrade (in Serbian). Geological map. GRAFIMEX, Belgrade. Y anev, S. 1993. Gondwana Paleozoic terranes in the Alpine Haydoutov, I. 1989. Precambrian ophiolites, Cambrian Collage System on the Balkans. -Journal ofHimalayan island arc, and Variscan suture in the South Carpathian Geology, 4, 2; 257-270. -Balkan region.- Geology, 9; 244-249. Zagorchev, I. S. 1992. Neotectonics of the central parts of Ivanov,T.,Misar,Z.,Bowes,RD., Dudek, A.. Dumurzhanov, Balkan Peninsula: basic features and concepts. - N.,Jaros,J.,Jelinek, E., Pacesova, N. 1987.1be Demir Geologische Rundschau, 81, 3; 635-654. Kapija - Gevgelija ophiolite massif, Macedonia, Zagorchev, I. 1994. Alpine evolution of the pre-Alpine Yugoslavia. - Ofioliti, 12, 3; 457-478. amphibolite-facies basement in South Bulgaria. - Jacobshagen, V. 1986. Geologie von Griechenland. Milleilungen der tJsterreichischen Geologischen Gebrueder Borntraeger, Stuttgart; 363 pp. Geselschajt. 86 (1993); 9-21. Kozhoukharov, D. 1986. Correlation of the Precambrian Zagorchev, I. 1995. Pirin. Geological Guideboolc. Academic in the southern parts of the Balkan Peninsula. - Publishing House .. Marin Drinov", Sofia; 70 pp. Geologicky Zbornik - Geologica Carpathica, 37, 3; 317- Zagorchev, I. 1995. Pre-Paleogene Alpine tectonics in 333 (in Russian). Southwestern Bulgaria - Geologica Balcanica, 25, 5-6. Mabel', M. ( ed.). 1974. Tectonics ofthe Carpathian-Ballcan Zagorchev, I., Tzankov, Tz. 1996. Geological Sites of regions. Explanations to the Tectonic map of the Special Scientific Importance (GSSSI): an approach Carpathian-Balkan regions. Geol. Institute Dionyz Stur, to Bulgarian and Balkan geotopes. - Geologica Bratislava; 456 pp. Balcanica, 26, 1; 51-56. Mariolakos, I., Papanikolaou, D. 1985. Deformation Zoubek, V. (ed.). l988.Precambrian in Younger Fold&IU. pattern and relation between deformation and seismicity European Variscides, the Carpathians and Ballcaru. J. in the Hellenic arc. -Bulletin of the Geological Society Wiley & Sons, Chichester; 885 pp. of Greece, 19; 59-76 (in Greek).

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