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Home , Alpine orogeny, Anatolian Plate, Cadomian Orogeny, East European Craton, East European Platform, Eurasian Plate

THE GEOLOGICAL AND TECTONIC FRAMEWORK OF

J.A. Plant1, A. Whittaker1, A. Demetriades2, B. De Vivo3, and J. Lexa4

1British Geological Survey, Keyworth, Nottingham, UK 2Institute of and Mineral Exploration, Athens, Greece 3University of Napoli Federico II, Naples, 4Geological Survey of Slovak Republic, Bratislava, Slovak Republic

Introduction

The geological record of Europe extends back structure has been greatly enhanced by the in time to about 3,500 million years, interpretation of new types of geophysical and approximately 1,000 million years after the geochemical data. The present of was formed. Europe was the birthplace of Europe stretches from its submarine continental geological sciences. The first writers who have margin in the west to the Ural in the contributed something of geological significance east, and from the ancient and relatively were the ancient Greek philosophers (Adams tectonically stable rocks of the Fennoscandian 1954), such as Thales of Miletus (c.636-546 BC), in the north, to the young, more Anaximander of Miletus (615-547 BC), tectonically and volcanically active zone, of the Pythagoras of Samos (540-510 BC), Xenophanes central and eastern Mediterranean in the south. of Colophon (540-510 BC), Herodotus of The evolution of the continent took place as a Halicarnassus (480-420? BC), Aristotle of Stagira result of lithospheric plate interactions, which are (384-322 BC), Strabo (64 BC-23? AD) and many now relatively well understood. The outer region others. Modern geology begins with Georgius of the Earth, or lithosphere, includes the crust and Agricola in (1494-1555 AD), who was the upper mantle, and is a rheologically more rigid one of the most outstanding figures in the history layer lying above a more plastic layer of the upper of the geological sciences, not only of his own mantle, known as the asthenosphere. The times, but of all time, and his rightfully called the lithosphere is divided into several major tectonic “Forefather of Geology”. Other eminent plates that move relative to one another, and pioneering figures are Leonardo da Vinci (1452- interact and deform, especially around their 1519 AD), Abbé Anton Lazzaro Moro (1687- margins. Orogenesis, involving crustal thickening, 1740 AD) and Antonio Vallisnieri (1661-1730 deformation and , is often followed AD) in Italy, Conrad Gesner (1516-1565 AD) in by extensional collapse with widespread intrusion Switzerland, Nicolaus Steno (1638-1686 AD) in of highly evolved peraluminous . Plume Denmark, Abraham Gottlob Werner (1750-1817 activity is generally associated with continental AD) in Germany, Jöns Jacob Berzelius (1779- break up, and there is considerable evidence of 1848 AD) in Sweden, William Smith (1769-1839 this following the splitting of the Earth’s most AD), the father of English Geology, Charles Lyell recent supercontinent – , beginning during (1797-1875 AD) and James Hutton (1726-1797 the Permo- times. At present, Europe AD) in the United Kingdom, Georges Cuvier forms the western part of the . In (1769-1832 AD) and Alexandre Brongniart the Mediterranean region it abuts against the (1770-1847 AD) in France, and Andreas to the south which, combined with Kordellas (1836-1909 AD) in Greece, working the broadly SE-directed ridge-push forces of the from the 15th to the late 19th centuries, to provide mid-Atlantic Ridge, and the beginning of an information on mineralogy, crystallography, eastward Atlantic plate compression along Iberia, palaeontology, and mineral resources. give a broadly NW-SE maximum horizontal Hence, the continent’s stratigraphy and structure crustal compressive stress throughout much of has been studied for almost 500 years. western and . Initially, geology involved the examination and Although the plate tectonic processes affecting survey of surface rock exposures to prepare Europe over the last 200 Ma period are reasonably geological maps. More recently, understanding of well understood, the earlier evolution of Europe’s the evolution of Europe’s continental crustal continental lithosphere has been extremely long

and complex and geological, and tectonic events The discussion of Europe’s geological are more obscure and difficult to interpret further evolution that follows should be read in back in time. To fully understand Europe’s conjunction with Sheet 9 (Europe) of the geology requires consideration of plate tectonic Commission for the Geological Map of the World processes and the changing geometry and (CGMW) (Choubert and Faure-Muret 1976), and geography of plates operating throughout the the recently published 1:5 million CGMW 3,500 Ma (3.5 Ga) of the evolution of the International Geological Map of Europe and continent. Adjacent Areas (Asch 2003).

Overview of the Geological and Tectonic Structure of Europe

Like all continental landmasses, Europe of the English Midlands, the southern presently comprises various crustal blocks, which , and Armorica extending from western have been assembled over geological time (Figure Iberia and eastwards through central 1). In the extreme northwest of , there is Europe to the Bohemian . The plate a fragment of the late continent of tectonic collision of Eastern with the , initially part of a North American- East European followed closure of the Greenland landmass. Otherwise, Europe’s Lower Palaeozoic Tornquist Sea in late continental basement can be divided broadly into to times. Whereas, the two large and distinct regions: collision of the Armorican micro-continent, with in the north and east a stable both the and Avalonia, craton known as the East European Craton followed the later closure of the Rheic and Theic (EEC), and (Galiza-Central Massif , e.g., Matte in the south and west a mobile belt, comprising 1991, Rey et al. 1997) probably towards the end crustal blocks that have become successively of middle . The southerly European attached to the ancient cratonic nucleus. Alpine orogenic belt is mostly of Caenozoic age. The boundary between these two regions is In Europe, the precise locations of separate marked by the NW-SE-trending Trans-European , -bounded blocks of continental Suture Zone (TESZ) (previously known as the crust, usually smaller than microcontinents, Trans-European Fault, the Tornquist Line or the related to Avalonia or Armorica are poorly Tornquist-Teisseyre Line), which extends for exposed and concealed beneath younger rocks. approximately 2000 km from the North Sea to the Also, in places, the reworking of older rocks in Dobrogea region of the . The TESZ is later has resulted in collages of everywhere obscured and concealed beneath relatively small shear-zone-bounded terranes and Caenozoic , but it has (such as the Precambrian Mona complex of North been reasonably well-defined as a broad zone of Wales, and similar complexes in the Bohemian NW-SE-striking faults by subsurface geology, Massif). drilling results and geophysical methods, Hence, the crystalline basement of western and including deep seismic reflection data. central Europe comprises a complex mosaic of The East European Craton (EEC) comprises crustal elements, assembled during various Precambrian rocks of the Baltic, and Precambrian orogenic cycles followed by the Voronezh shields, together with the Russian or Caledonian, Hercynian and Alpine East European , where the EEC is orogenies. During this long and complex crustal covered by relatively thin, undisturbed, evolution, earlier consolidated crustal elements Phanerozoic rock sequences. In contrast, the were repeatedly remobilised and overprinted by mobile belts to the south and west comprise later events. Thus, the basement provinces of Proterozoic-Palaeozoic crustal blocks (or western and central Europe are defined by the ‘microcontinents’), which originated as part of the latest orogenic event affecting that portion of southern continent, tectonised by end- crust, causing widespread metamorphic reworking Precambrian Cadomian orogenesis that became and, in many cases, the intrusion of calc-alkaline attached to the south west margin of the EEC in igneous rocks. Palaeozoic times. These crustal blocks, belonging The oldest Precambrian basement provinces of to Eastern Avalonia, now form part of the western and central Europe, therefore, comprise

the East European and Hebridean , the poorly defined, partly as a result of a lack of data, stable Cadomian blocks of the London Platform and partly because they are concealed by younger and the East Silesian Massif, and the Caledonian, rocks. Also, metamorphic overprinting of some Variscan and Alpine belts. The boundaries older basement areas has occurred during later between the principal structural elements of the orogenic cycles. This is particularly the case with European continental elements are in places the Variscan fold belt, which in places seems to

Figure 1. The ‘ collage’ of Precambrian and Phanerozoic Europe, a simplified sketch. Sutures and orogenic fronts are shown as bold lines, internal borders as thin or thin broken lines. Note that the size and shape of the terranes do not change significantly with time (approximate direction of younging is from north to south) (Reproduced with permission from Blundell et al. 1992, and Plant et al. 2003, Fig. 1, p. B229).

contain some Caledonian, as well as the Late including pre-Variscan basement, late-Variscan Palaeozoic (Devonian-early ) granitoids and post-Variscan volcaniclastic rocks, orogenic belts. Similarly, throughout the of occur in many places. , pre-Alpine basement rocks,

Precambrian Europe

The Laurentian Shield inliers of Laurentian affinity are also found in the Caledonian orogen as basement to the Moine The small outcrop of Laurentian, the Lewisian Supergroup rocks of northwest Scotland. Complex of NW Scotland, has remained tectonically stable since Proterozoic times. It The Fennoscandian Shield consists mainly of Archaean granodioritic, tonalitic and amphibolitic gneiss, formed under The most extensive area of exposed and facies conditions at Precambrian rocks in is in the c.2,700 Ma and 2,470 Ma. The protoliths of the Fennoscandian Shield, which comprises four main Lewisian Gneiss Complex consist of granodioritic NW to SE trending orogenic belts with the rocks and tonalitic intrusions, bodies, layered generally younging southwestwards (Figure 1). mafic-ultramafic bodies, mafic dykes and From NE to SW these comprise: lenticular bodies, and minor metasedimentary the Kola-Karelian Orogen that consists of five rocks. Recent U-Pb zircon dating has shown that Archaean terranes amalgamated by collision these range from 3,125 Ma to c.2,700 Ma. The between 2.0-1.9 Ga; rocks were subject to deformation at middle to the Svecofennian Orogen is made up of rocks lower crustal levels under granulite and upper younger than <2.2 Ga, which accreted and amphibolite facies conditions during the Scourian underwent collisions between 2.0-1.8 Ga, and event between c.2,650 Ma to 2,480 Ma. The were reworked by crustal melting between 1.8- Archaean architecture of the complex was 1.54 Ga; completed by intrusion of sheets and the Gothian Orogen, comprising rocks accreted around 2,550 Ma, mainly in the Outer between 1.77-1.5 Ga, is thought not to contain Hebrides. A major suite of Early Proterozoic older rocks, and tholeiitic dolerite and dykes, the Scourie the Sveco-Norwegian Orogen was dated at Dyke Suite, was intruded into the complex in two 1.05-0.9 Ga, and reworked most of the Gothian phases at c.2,400 Ma and c.2,000 Ma, with the Orogen. former phase accompanying local shear zone formation. Arc-related metasedimentary and The Kola-Karelian Orogen metavolcanic rocks were later accreted to the complex in the South Harris and Loch Maree This orogenic belt has distinctive geophysical areas at around 1,900 Ma. The terranes were then properties compared to the Svecofennian Orogen. largely reworked during a Laxfordian It has an average crustal thickness of 45 km with tectonometamorphic event that peaked at c.1,750 an upper layer interpreted as mainly magnetic Ma, and took place under amphibolite facies diorite, and an facies transition at 38 km. conditions. Only the area centred on Assynt, and In the extreme NE, the Murmansk gneiss- small parts of the Outer Hebrides, avoided this granulite terrane consists predominantly of penetrative reworking. Laxfordian granite sheets tonalitic gneiss, granodiorite, amphibolite and were intruded at c.1,855 Ma on the mainland, but , and minor granulite, pyroxene gneiss considerably later at c.1,675 Ma in Harris and and , with intercalated banded ironstone Lewis. The area was uplifted prior to 1,100-1,200 formation, metamorphosed in the upper Ma ago when the older Torridonian Supergroup amphibolite-granulite facies. The major structures rocks were deposited. Some possible Grenvillian are large-scale reclined folds intruded by plutons shear zone effects are recorded by uplift dates of late Archaean granitic rocks. Uranium-Pb from the highly deformed Langavat meta- zircon ages obtained on gneiss are 2.9-2.7 Ga. sedimentary belt in South Harris. Lewisianoid Adjacent to this terrane, to the southwest, the

composite Sørvaranger terrane major greenstone belts up to 100-150 km long consists of: have been recognised, as well as many smaller two greenstone belts comprising amphibolite, ones, separated by belts of gneiss with different ultramafic rocks and agglomeratic meta- types of granite intrusions. Across eastern Finland volcanics and meta-psammite, , banded and Karelia, there are four tectonic zones with ironstone formations and quartzite, mostly at different compositions and ages of volcanic rocks amphibolite facies, and in the greenstone belts. The composition and ages amphibolite to granulite facies migmatitic of the gneiss and granite, and their degree of alumino-silicate schist and gneiss in thrust metamorphism and deformation also varies. contact with the greenstone belts. The Tholeiitic basalt makes up 40-70% of most discordant Neiden granitic pluton intruding greenstone belts, although some include magmatic greenstone belt rocks and the gneiss have a U- rocks, ranging in composition from komatiite to Pb and Rb-Sr age of 2.5-2.55 Ga. It has been . The greenstone belts young westwards suggested that the greenstone belts formed in from 3.0-2.9 Ga in eastern and central Karelia, to arc and back-arc settings, while the gneiss is 2.80-2.75 Ga in western Karelia, and 2.65 Ga in derived from , laid down in an arc- eastern Finland, consistent with the progressive trench (Windley 1992, westward of successive island arcs, 1995). above eastward-dipping zones. The The Inari gneiss terrane consists of gneiss and granite are less well understood than heterogeneous migmatitic trondhjemitic to the greenstone belts. Some consist mostly of granitic orthogneiss within which there are conformable layers and lenses of amphibolite and paragneiss, while others comprise mainly of schist up to 10 km wide, associated locally orthogneiss and granite. Many show a close with calcic gneiss, quartzite and banded ironstone spatial and temporal relationship with the formation. Uranium-Pb determination on zircon development of the greenstone belts. The oldest from the gneiss gives dates of 2.73-2.55 Ga. known rock in the is gneiss in The composite Belomorian terrane contains: southeastern Karelia, which gives U-Pb zircon amphibolite-facies meta-pelitic gneiss, ages of 3.5 Ga. Amphibolite and migmatite are orthogneiss, amphibolite and granite. Uranium- dated at 3.2 Ga, and tonalite spans the time range Pb determinations on zircon from the tonalitic- of 3.4-3.1 Ga. trondhjemitic gneiss give ages of 3.11 Ga, and The orogen was formed in the Early Nd isotopes suggest that the crustal material Proterozoic between 2.0-1.9 Ga as the Archaean had separated from the mantle by 3.5 Ga. terranes collided, and eventually amalgamated Other types of gneiss in this terrane are dated with Early Proterozoic (2.4-1.9 Ga) rocks. Island in the range 2.9-2.4 Ga, and arcs, Andean-type magmatic arcs, sutures and in Finland, the Lapponian Supergroup, which remnant shelf successions were all included. The includes several greenstone belts that have a southern border of the Murmansk Terrane is lower unit of komatiitic and tholeiitic basalt, marked by a northward dipping (60-80º) thrust mafic to (part of a plateau lava), a zone several-kilometres wide, which deforms central unit of pillow-bearing amphibolite, large-scale folds. The Kola suture zone is a arkosic quartzite and aluminous slate, and an southward-dipping thrust zone up to 40 km along upper unit of extensive ultramafic and basaltic which the Inari terrane is thrust over the komatiite, mafic lava and tuff, carbonaceous Sorveranger terrane, while the Sirkka thrust is a and graphitic slate. The Kittilä major tectonic boundary along which the high- (island arc) greenstone belt is cut by a gabbro grade Belmorian terrane was thrust southwards dated at 2.44 Ga, and in the eastern under the low-grade Karelian terrane. Belomorides a 2.7-2.6 Ga period of collision has been recognised. The Svecofennian Orogen The basement of the Karelian composite terrane comprises Archaean greenstone belts The Luleå-Kuopio suture zone separates the comparable to modern island arc assemblages, Kola-Karelian orogen in the NE from the separated by gneiss and granite. More than 20 Svecofennian orogen to the SW. The suture zone

is displaced by 1.9-1.8 Ga north-south mega- into exposed basement as , framed as a result shears, which have a strong magnetic signature, of the extension and thinning of the Sveco- and are associated with a of the Fennian crust. Mohorovicic discontinuity of about 10 km. The Along the SW margin of the Svecofennian suture contains thrust slices of different types and orogen the 1600 km long, 150 km wide Trans- origin, including two types of turbidite: Scandinavian Batholith (1.84-1.75 Ga), which those on the Archaean craton, immediately to includes early arc-type monzodiorite to quartzo- the NE of the suture, where autochthonous monzodiorite and granite, and later . turbidite contain Archaean and Proterozoic The batholith may have developed above an detritus locally interbedded with tholeiitic eastward-dipping subduction zone on the western volcanics, and margin of the Sveco-Fennian orogen. those in the suture that comprise allochthonous turbidite, deposited from debris flows and The Gothian Orogen turbidity currents in submarine canyons at an accretionary margin. A small part of the Gothian orogen, which The suture zone also contains serpentinite, escaped Sveco-Norwegian reworking, is gabbro, basaltic , non-detrital quartzite, preserved in the extreme southeast of Sweden, and dolomite, Mg-rich meta-volcanics and Cu- on the island of Bornholm, Denmark. There, acid sulphide deposits. meta-volcanics with a U-Pb age of 1.705 Ga, The Svecofennian orogen contains no metabasite, quartzite, mica schist and gneiss with Archaean terranes, and is thought to have a U-Pb zircon age of 1.69 Ga, and intrusive developed by the growth and accretion of juvenile granite are preserved. The oldest known Gothian arcs dated at 2.0-1.8 Ga, and by extensive crustal rocks here is amphibolite dated at 1.77 Ga, melting in the period 1.8-1.55 Ga. The orogen has associated with paragneiss deformed and a mainly paramagnetic dioritic upper crustal layer, metamorphosed under amphibolite conditions, and an average crustal thickness of 48 km and intruded by numerous calc-alkaline tonalite- (maximum 54 km) and a thick lower crustal layer. granodiorite bodies. During a period of crustal The orogen comprises several magmatic arcs extension, between 1.5-1.25 Ga rapakivi granite, with rocks and ores comparable to those of gabbro and basic dykes were emplaced, bimodal modern island arcs and intra-arc rifts. The 1.89 Ga volcanics were extruded, and clastic sediments Skellefte island arc has mature intra-arc volcanics were deposited in rifts in the eroded basement. and granodiorite-granite intrusions derived from subduction-related melts. Uranium-Pb zircon data The Sveco-Norwegian Orogen suggest that most of the Svecofennian arc lavas were erupted between 1.92-1.87 Ga, The Sveco-Norwegian was a contemporaneous with the intrusion of 1.91-1.86 cordilleran type collisional event that reworked Ga subduction-derived plutons and tonalitic, the Gothian crust, and produced a north-south granodioritic and granitic batholiths. Many of the trending belt. It comprises meta-, tuff, Sveco-Fennian arcs are separated by - , and volcanic breccia, with syn- bearing granitic gneiss and schist, widely regarded orogenic calc-alkaline plutons and post-tectonic as meta- and meta-pelite, which contain granite. The isotopic age of the supracrustal rocks numerous large lenses of amphibolite, metagabbro is 1.25-1.2 Ga. The geochemical features of the and meta-ultramafic rocks. Nickel-Cu deposits earliest basalt, acid volcanics and gabbro occur in some peridotite-dunite-pyroxenite-gabbro intrusions are consistent with formation in an lenses. Following arc accretion, syn- and post- extensional, continental margin setting, related to collisional deformation took place. Thrusting and the subduction processes. These culminated in the folding was associated with high amphibolite Sveco-Norwegian orogeny between 1.05-0.9 Ga, facies metamorphism that locally reached marked by deformation and associated upper granulite grade, followed by the emplacement of amphibolite facies metamorphism. rapakivi granite. The last event in the evolution of Subsequently, the late Proterozoic East the Svecofennian orogen was the deposition of the European craton drifted towards equatorial at 1.5 Ga in a large elongate latitudes. The development of the Vättern basin in the Gulf of Bothnia. Locally, this extends system in southern Sweden reflects rifting during

this time (850-700 Ma) when up to 1 km of Caledonian fold belts is confined to outcropping fluviatile to marine clastic sediments were down Palaeozoic massifs, whereas a few radiometric faulted, close to the eastern border of the Sveco- age determinations are available from deep Norwegian orogen, unconformably overlying the boreholes, drilled through the overlying marginal shear zone. sedimentary basins. Hence, there is uncertainty about the relationships of the concealed fold belts. The Cadomian Orogen The metamorphic Irish-Scottish-Scandinavian Caledonides form a NE-SW trending belt across The between 650-550 Ma NW Europe, interrupted by the later Irish and (late Precambrian) was the last in the sequence of North Sea basins. Offshore deep borehole samples events that formed the crystalline basement rocks give age determinations that indicate the of Europe. The Caledonian and Hercynian continuation of the Caledonides of northern basement complexes of western and central Britain and . In early Silurian times, a Europe, not to mention some basement inliers Gondwana-derived terrane, Eastern Avalonia, within the Alpine-Carpathian orogen, contain approached the newly-united of several continental crustal blocks derived during Laurentia and (). Strike-slip and the Cadomian orogeny. These include the Irish transpressional movement along the Avalonia- Sea Horst, the London Platform, the Armorican Laurasia suture persisted until the end of the and Bohemian cratons, the East Silesian block and Silurian and caused the development of the the Malopolska Massif of south eastern . English-North German-Polish Caledonides. Thus, Cadomian crustal elements are also recognised in the Caledonian orogenic cycle eventually the Alpine fold belt, based on their geology and involved the closure of the Iapetus, the Tornquist radiometric age dating. Following the Cadomian and the Rheic oceans. orogeny, deep rifted sedimentary basins The Iapetus suture between the Laurentian developed across Proterozoic Europe, and the tectonic unit to the NW, and a segment from the wide ocean known as the Tornquist Sea opened. composite Gondwana-derived Irish Sea-London At the end of the Proterozoic, Europe drifted Platform-Brabant Massif cratonic terrane to the towards high southern latitudes, where the south-east, is marked by the Solway Line in Gondwana continent was assembling [Pan African Britain and . Deep seismic reflection data – Cadomian orogenies (650-550 Ma)]. It remained and the distribution of Ordovician faunal in these high latitudes during times. provinces, suggest that the position of the north- However, by the Early Ordovician those parts that dipping Iapetus suture is located approximately now constitute the Fennoscandian Shield, and the along the border between and Scotland, basement of the , had passes to the north of the Isle of Man, and thence broken off and drifted away as an independent crosses Ireland in a south-westerly direction tectonic plate. ‘Baltica’ eventually became a where it is covered by Lower Carboniferous rocks ‘nucleus’ of the future Caledonian terrain of (Figure 1). . Other parts of the former During Cambrian and Ordovician times much Proterozoic Europe, which had become attached of Baltica and the Laurentian crystalline block to Gondwana, and were strongly influenced by the that included north-west Scotland were covered Cadomian orogeny, were left behind for the time by shallow epicontinental seas. Over the East being. European Platform sedimentation continued with little break throughout the Palaeozoic, continuing The Caledonian Orogen in places into the Mesozoic. Generally, the Precambrian basement of the East European The Caledonian orogenic cycle occurred Platform now lies at a shallow depth (1-3 km) between Late Cambrian and earliest Devonian beneath relatively thin Phanerozoic cover. In the times, and reflects the collision of the late Ukrainian Massif, the basement is exposed, and in Proterozoic continents of Baltica, Laurentia and the Voronezh Massif the cover sequence is Avalonia, a fragment of Gondwana. It marks the shallow enough to permit opencast mining of complex closures of the Iapetus or Proto-Atlantic Archaean and Proterozoic banded ironstone Ocean. Throughout much of Europe information formations. on the distribution and age of deformation of Although the Iapetus suture in the

is relatively well-defined, its northward Basin extension to south-west Iberia, is continuation beneath the northern North Sea Basin represented by the Visean-Upper Westphalian is not. The Tornquist suture is thought to branch south-western prograded , in the South from the Iapetus suture beneath the central North Portuguese Zone, located south-west of the Beja- Sea Basin, and strike southeastwards into north Acebuches suture (present coordinates). Germany and Poland, where it follows the margin South of the Rhenohercynian Zone, the of the Precambrian East European Platform. The contains the Mid-German Rheic suture is considered to be located in the crystalline high, which acted as an active margin. mid-European Caledonides, in the Saxothuringian It was the site of arc magmatism during the early and Moldanubian terranes. Carboniferous collisional phase, and the source region of the Rhenohercynian flysch. Southwards, The Variscan Orogen the crystalline high has been thrust over the Palaeozoic sequences of the Saxothuringian The Hercynian orogenic cycle, which took Basin, which are exposed in Bavaria, Thuringia place between the Devonian and Early , and Saxony, and the northern parts of the Black involved the assembly of the Earth’s latest Forest and . The Iberian equivalent of that supercontinent – Pangaea. At this time, almost all zone is the Ossa-Morena Zone, which acted as an of the present Continents were distributed in one active margin with arc magmatism, during the approximately North to South crustal mass, with a Westphalian collisional phase. Nevertheless, as few blocks such as those of Armorica, Iberia and opposed to these areas, the kinematic polarity is to Bohemia situated between it and the larger the SW, compatible with the NE deep of the Beja- Laurentian-Baltic (Laurasia) terrain to the NW. Acebuches suture. The term Variscan refers to the European part of The Saxothuringian rocks are in turn overthrust the Hercynian orogen or fold belt, and specifically by of virtually unmetamorphosed relates to the time of late Visean–Westphalian Palaeozoic deeper water facies and crystalline consolidation. Variscan extension throughout rocks, derived from the NW margin of the western and central Europe in early Devonian Moldanubian region to the south-east. The times led to the development of the internal structure of the is Rhenohercynian Basin, filled with thick Devonian complex. In places, SE-directed thrusts and Carboniferous sediments in a double arc. emplace high-grade over medium grade These relatively undeformed Late Palaeozoic metamorphic sequences. Similar features in the sediments can be traced in the foreland of the suggest their possible occurrence in Variscan fold belt north of the Variscan the intervening parts of southern Germany, where deformation front, from southern Ireland in the the Variscan basement underlies thick Mesozoic west, through Britain and Belgium into northern cover. To the south, the Moldanubian zone Germany, northern Poland and then further east probably continues into the Variscan basement of beneath Slovakia, some 2,500 km. The Rhenish the Alps, while to the south-west the Avalon- Basin beneath the , north Germany Meguma-South Portuguese and the Aquitaine- and much of the southern North Sea, extends Cantabrian terranes collided with the Proto- northwards into the Devonian and Carboniferous Tethys-Proto-Atlantic subduction complex during rift systems of northern Britain and, then south- the late Emsian to Givetian. This collisional event, westwards through Ireland. It extends eastwards marking the closure of the Merrimack and Massif in the NW-SE trending Lower Silesian Basin Central oceanic basins, corresponds to the beneath much of northern and central Poland. Acadian-Ligerian orogeny of . The Polish basins were connected laterally with In Middle and Late Devonian times, the the sedimentary deposits of the East European continental masses of Laurasia and Gondwana Platform and the during Upper began to converge to form Pangaea. Progressive Palaeozoic times. Here, much of the narrowing of the Proto- allowed Rhenohercynian Basin is buried beneath many early contacts between Laurasia and Gondwana in kilometres of Permian and younger sediments, the region of Iberia and NW during the although its distribution is reasonably well known Fammenian Stage, thus allowing an exchange of as a result of numerous boreholes drilled in the flora and fauna between these previously distinct Northwest European Basin. The Rhenohercynian geographical provinces. Full collision, between

Africa and the southern margin of Fennoscandia- crustal shortening in the Variscan fold belt ended Baltica, happened during the late Visean, while during Westphalian times.

The Mesozoic Development of Europe

Following the early Permian consolidation of synchronous with the repeated advance of deltaic Pangaea, the supercontinent soon began to show systems from the Fennoscandian High and the signs of instability. The extensional reactivation EEC across the northern North Sea, Denmark and of pre-existing faults, after the Variscan the Southern areas. compression, and the formation of new rifts in late During the period, the break up of the Permian and Triassic times, allowed the supercontinent of Pangaea began along the central development of many large sedimentary basins. Atlantic axis. Middle and Late Jurassic opening Although there was no crustal separation in of new oceanic basins also occurred in the Europe in Permo-Triassic times, basinal structures Mediterranean area, and Gondwana became provided an early indication of the extent of future separated from Laurasia, after having formed part Jurassic, and early Caenozoic break- of Pangaea for about 100 Ma. In Europe, late up of Pangaea in the Arctic, North and Central Triassic-early Jurassic times commenced with a Atlantic and Mediterranean regions and, thus major transgression of the Tethys Sea and the initiated a new and different reorganisation of establishment of a broad, open-marine shelf sea plate boundaries that eventually led to the present that occupied much of southern Germany, the day distribution of continents. , the -Western Approaches Large quantities of clastic sediments, in some region, the Irish Sea, the southern and central cases associated with volcanic rocks, were North Sea, Denmark and northern Germany. The deposited in many of the Permian basins. Many open marine seas, producing mudstone, and of the depocentres have trends related to pre- minor in the more westerly parts of existing structural directions. On a European Europe, also had a clastic input from the EEC into scale, one of the most important sites of basin the Northwest European Basin. The middle and development was along the TESZ, where late Jurassic evolution of western and central geophysical data and drilling have identified deep Europe was dominated by crustal extension across NW-SE trending basins under thick sequences of the north Atlantic rift system accompanied by a younger cover rocks. The early Permian basins changing regional stress pattern, which caused along the TESZ also influenced the development important changes to the palaeogeography. of the hypersaline late Permian Zechstein Sea in Various factors such as a changing stress regime, which important evaporite deposits were formed. and the collapse of the North Sea rift dome, The later halokinesis of these salt deposits to form resulted in changes to the shape of basins and numerous salt diapirs has played an important role their sources of clastic detritus. in the entrapment of hydrocarbons in Europe. The The early Cretaceous development of Europe two main North and South Permian basins that continued to be dominated by crustal extension, now underlie much of the North Sea and north associated with the north Atlantic rift system, with Germany, were separated by the roughly E-W few changes in structural framework and on basin trending Mid-North Sea-Ringkobing-Fyn High. development. On a larger scale, tectonic activity Some of the important Permian depocentres increased at the Jurassic-Cretaceous transition. continued into the Triassic, which also saw the initiation of a complex multidirectional rift system The Alpine Orogen that crossed the Variscan fold belt. The Triassic rocks consist of continental to brackish marine red Pre-Alpine basement rocks of Caledonian and beds, shallow marine carbonates, sulphates and Variscan and Hercynian age outcrop in scattered halites. An overall eustatic rise in sea level, during areas of the Alps, and are most abundant in central Triassic times, was reflected by the Triassic Europe, where high grade crystalline rocks are sediments overstepping Permian basin margins. exposed north of the extensive uplift and During Late Triassic times, the clastic-evaporite caused by the . The basement regime of the Northwest European Basin was rocks comprise a mixture of pre-Variscan

basement, Late-Variscan granitoids associated zone between Europe and Africa since Jurassic with clastic and volcaniclastic rocks, and post- times, when the Atlantic opening reactivated the Variscan volcaniclastic rocks. Data from the Alps east-facing Tethyan passive margin. The indicate that there were at least two distinct major microplate is now buried deep beneath the cover episodes of tectonic activity, one during the of Mesozoic sediments, and clastic Cretaceous and a later one in the . This foredeep fill, shed from the rising Alps and second, and later phase of Tertiary convergence, Apennines. South Alpine thrusting occurred results from N-S to NNE-SSW directed plate during Palaeogene, , and Plio- motions between Europe and Africa in the events. More recently, thrust have been , and NW-SE directed motions in the reflected by devastating earthquakes for example Miocene. To the north of the Alps, a foreland the 1,976 AD earthquake near Gerona, and basin had developed in late Eocene times, its possibly in 1,348 AD near Villach. Beneath the depocentre migrating northward in response to , some of the most recent loading and flexure of the lithosphere caused by interpretations, based on deep seismic data and the of Europe and Africa. To geology, indicate an emplaced thrust sheet the south of the Alps, in the Po Basin of Italy, a involving 10 km of pre-tectonised crust intruded foredeep in which syntectonic sediments by arc magma, overlain by 5-7 km of Mesozoic accumulated was linked to the south-vergent passive margin sediments, and 3-7 km of thrusting in the southern Alps. In the western and to Pleistocene foredeep fill. Its frontal , the rotating WNW motion of the part is a blind thrust within the Miocene section Adriatic microplate was associated with and its foreland imbrications, a zone that includes transcurrent faulting. The late stages of the many of Italy’s major oil and gas fields. collision, produced spectacular large-scale During the Neogene and the backfolds in the nappes of the central convergence direction between and Alps, movements related to a wedge of Adriatic Africa-Arabia gradually changed, and was crust, which was forced into the European crust. dominated by dextral translations. This was Shortening of the entire south Alpine fold- and coupled with the development of intra-Alpine thrust belt is of the order of 70-115 km. The latest shear systems, the concentration of crustal movements of the collision reflect the north- shortening to the Western Alps and the Eastern westwards motion of the African plate relative to Carpathians, and the subsidence of the Pannonian Europe, giving rise to a complex pattern of earth Basin (Ziegler 1988, 1990). Neogene and movement reflecting convergence. Quaternary sediments exceed a thickness of 4 km The Alps continue to be affected by a crustal in the deeper parts of the , and stress regime, associated with crustal thickening, locally reach 7 km in the deepest . At although in the central Alps rising topography is present, the Pannonian Basin is still seismically already counterbalanced by the beginnings of active and continues to subside (Sclater et al. extensional collapse tectonics. Fold belts at the 1980, Royden et al. 1982, Horváth et al. 1986, Alpine northern front of the Alpine belt record the 1988). latest supracrustal trace of the Europe-vergent The tensional subsidence of the Neogene collisional suture, which intersects the Moho a Pannonian Basin, and also the Aegean back-arc short distance north of the Alpine south front. The basin, both of which developed during the Late latter is a south-vergent back thrust antithetic to Alpine orogenic cycle, was associated with major the collision suture. In contrast, the Apennines wrench deformations and important crustal were undergoing extension with mid-crustal and shortening in the related arc systems. These deeper detachments and metamorphic core deformations are, to a large extent, the expression complexes, and the formation of new oceanic of changes in the convergence direction between crust within the main body of the orogen. the colliding continents, and also of indent effects The cratonic Adriatic microplate is the and ensuing “escape tectonics” (Ziegler 1988, foreland of both the Alpine and Apennine 1990). orogens, and has been part of the transtensional

Caenozoic Volcanic Activity

Early Tertiary volcanics, associated with the including differentiated rocks, subvolcanic splitting of the , extend from east intrusions, rare late stage rhyolite, and epithermal Greenland to the Hebrides, to the coast of mineralisation. Middle Miocene to Pleistocene Portugal and to Morocco. Other volcanic ‘hot intermediate volcanism of the same affinity in the spots’, decreasing in age from south to north and arc setting (eastern Carpathians) has given rise to west to east, extend from the Faroe Islands to mostly basaltic andesite, andesite stratovolcanoes, , and from Wroclaw in Poland to the Eifel and/or small subvolcanic intrusions with rare Mountains in Germany respectively (Duncan et differentiated rocks. Sporadic to al. 1972, Ager 1975, 1980). Caenozoic volcanics Quaternary alkaline basalt volcanism produced, in also occur in the Central Massif of France, the western and northern parts of the Pannonian Catalonia, La Mancha, Almeria, Alboran and Basin, volcanic fields with lava flows, scoria Canary Islands in , the Carpatho-Pannonian cones, maars and diatremes (Horváth and region, and the volcanic provinces of Italy (Figure Berkhemer 1982, Stegena and Horváth 1982, 3) and Greece (Figure 4). Royden and Horváth 1988, Póka 1988, Ziegler 1990, Lexa and Konečný 1998). Caenozoic volcanism in the Carpatho- The change from calc-alkaline to alkaline Pannonian Region basaltic volcanism followed the termination of crustal shortening in the northern and eastern Tertiary to Quaternary volcanicity is closely Carpathians. Thus, it could be envisaged that connected to the structural evolution of the steepening of the Carpathian subduction zone may Carpathian arc and Pannonian Basin. Subduction have contributed towards the further development of the flysch basin floor in the convex front side of upwelling mantle currents in the Pannonian of the Carpathian arc commenced in early back-area (Royden and Horváth 1988, Ziegler Miocene in the west, and was concluded during 1990). The Plio-Pleistocene decay of the west- Pliocene to Quaternary in the east. A subduction dipping Carpathian subduction system was rollback was compensated by a coeval back-arc accompanied by alkaline volcanism, and only extension in the Pannonian Basin. limited back-arc extension (Horváth and Royden During late early Miocene, the Pannonian 1981, Royden 1988, Ziegler 1990). Therefore, Basin began to subside under a transtensional development of the Pannonian Basin can be setting on top of the Carpathians and East Alpine directly related to changes in the convergence nappes (Royden and Horváth 1988, Ziegler 1990, direction of Europe and Africa-Arabia. Lexa and Konečný 1998). The Oligocene-earliest Miocene diastrophism was of major importance in Caenozoic volcanism of the European Rift the , and exceeded by far the System intensity of intra-Miocene compressional movements (Brix et al. 1977, Kröll 1980, Wessely The Tertiary to Quaternary volcanicity of the 1987). Following the Oligocene-early Miocene European Rift System (Massif Central and diastrophism of the northern Carpathians and the Auvergne in France, Graben and Eifel in Dinarides, the area of the Pannonian Basin was Germany, Eger Graben in Bohemia) is uplifted, and its central and north-eastern parts characterised by mostly volcanic fields of tefrite, became sites of extensive silicic volcanism of basanite, alkali basalt and/or hawaiite lava flows, high-potassium calc-alkaline affinity (early to scoria cones, maars and diatremes, in a lesser middle Miocene), giving rise to extensive dacitic extent trachyte and phonolite extrusive domes, to rhyolitic ignimbrite, tuff and reworked tuff, rare tholeiitic basalt stratovolcanoes. which were subsequently covered by younger sedimentary rocks (Lexa and Konečný 1998). Tertiary British Volcanic Province Middle to late Miocene intermediate volcanism of medium to high-potassium calc-alkaline Volcanic activity in the British Volcanic affinity in the back-arc setting (central Slovakia, Province is related to rifting and the opening of northern , Apuseni Mountains in the northern Atlantic. It consists of mostly Romania), produced andesitic stratovolcanoes, alkaline to tholeiitic plateau basalt (icelandite,

hawaiite, mugearite), and gabbro/granite northward dipping African plate, where it is being subvolcanic intrusive complexes. Tertiary subducted into the mantle beneath the overriding volcanics occur in northern Ireland and north- Eurasian plate. Shallow-focus earthquakes are the western Scotland, basaltic lava flows (e.g., the most destructive, in terms of loss of life and Giant's Causeway and the northern part of the isle damage to human infrastructure, and are normally of Skye) are associated with northwest–southeast- generated in the vicinity of divergent boundaries. trending basaltic dykes and many plutonic Within Greece and neighbouring countries, complexes. The dykes extend south-eastwards over two and a half thousand earthquakes with across northern England and continue under the magnitudes of 5 to 8.3 Mw have occurred between North Sea. 550 BC to 1999 AD. One of the most destructive earthquakes that affected the Eastern Seismic and volcanic activity in the Eastern Mediterranean happened on the 21st July 365 AD Mediterranean region of Italy and Greece on the island of Crete, and uplifted its western part by up to nine metres (Guidoboni et al. 1994, At the present time, tectonic activity in the Drakos and Stiros 2001). Its magnitude is eastern Mediterranean is related to the northward estimated to have been 8.5-8.7 on the Richter movement of the African and Arabian plates scale. against the Eurasian and Anatolian plates, reflected by intense seismicity and volcanic Caenozoic volcanism in Italy activity in Italy and Greece (Figure 2). Deep-focus earthquakes that originate at Italian volcanism is related to the structural depths greater than 100 km coincide with the evolution of the , which comprises

50o 50o

40o 40o

30o 30o

-10o 0o 10o 20o 30o

m/s2 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.3 1.6 2.0 2.5 3.0 6.0 m/s2

Figure 2. Horizontal Peak Ground Acceleration seismic hazard map for the Mediterranean region, representing stiff site conditions for an exceedance or occurrence rate of 10% within 50 years. Major damage occurs when ground acceleration exceeds 2 m s-2 (light orange to brown), which is about 20% of the acceleration of gravity (from Grünthal et al. 1999, Fig. 4).

two small extensional basins floored by oceanic The Tuscany province consists of both mafic crust. Extension began in the Late Tortonian at the and acid rocks. Acid rocks are either of crustal margin, and propagated eastwards anatectic origin or, more commonly, reflect reaching the Marsili basin in the Pleistocene. mixing of crustal and various mantle derived Oligocene-Miocene calc-alkaline volcanism is melts. Mafic rocks have lamproitic and thought to reflect the NW subduction of the shoshonitic-potassic-calk-alkaline affinity leading edge of the African plate beneath the (Peccerillo 2003). European palaeomargin, which opened the To the South, The Roman province comprises Balearic Provencal basin and rotated the Sardinia- potassic and high-potassium rock series (HKS) Corsica block anti-clockwise. Volcanism, related with varying degrees of evolution. to this subduction, migrated eastwards from the The Umbria ultra-alkaline province comprises Oligocene-Early Miocene arc of Sardinia to the small centres of ultrapotassic olivine melilite, in the Pleistocene arc. associated with carbonate-rich pyroclastic rocks, Pliocene-Quaternary magmatism, in central which have been suggested to represent and southern Italy, generated a large variety of carbonatitic magmas (Stoppa and Wolley 1997). rock types ranging from mafic to acid, tholeiitic to The Ernici-Roccamonfina province displays calc-alkaline, Na- and K-alkaline and ultra- characteristics transitional between the Roman alkaline, in a volcanic belt that extends from and Neapolitan provinces, and is characterised by Tuscany in the north, to the Southern Tyrrhenian the close association of potassic and high Sea and in the south. potassium magma; the former rocks display Recent studies indicated a complex geotectonic incompatible trace element contents, and Sr-Nd setting, comprising at least seven compositionally isotopic signatures close to those of the distinct magmatic provinces (Peccerillo and Panza Neapolitan volcanoes, whereas the latter resemble 1999) (Figure 3). Roman HKS rocks.

Tuscany province Umbria ultra-alkaline province

Roman Rome Province Ernici-Roccamonfina province Mount Vulture Neapolitan- province Eastern Aeolian arc province Tyrrhenian Sea Western-central Aeolian arc province

Ustica Na-alkaline volcanoes Etna Iblei

0 100 200 km

Figure 3. Caenozoic volcanic provinces in Italy.

The Neapolitan province is characterised rocks typical of island arcs and the eastern mainly by ignimbrites and alkaline rocks of Aeolian arc, including Stromboli, comprising Campi Flegrei and Vesuvius (Ayuso et al. 1998, rocks ranging from calc-alkaline to shoshonitic De Vivo et al. 2001). Their composition varies and potassic composition, similar to those of the from potassic to high potassic, though calc- Neapolitan volcanoes (Peccerillo 2001b). alkaline rocks. The mafic volcanic rocks have Mount Vulture lies to the east of Vesuvius, in trace element ratios, and isotope trends, the southern Apennines and comprises alkaline comparable with those of Stromboli in the eastern rocks enriched in Na and K. Recently erupted Aeolian arc and Vesuvius, and other Neapolitan magmas have been interpreted as carbonatite volcanoes are thought to represent the northern (Stoppa and Wholley 1997). extension of the Aeolian arc (Peccerillo 2001a). The Na-alkaline volcanoes of Etna, Iblei, The Aeolian arc province comprises the Ustica and the Sicily channel (Linosa, Pantelleria) western sector, predominantly calk-alkaline, with form a distinct magmatic province, of typical

F.Y.R.O.M. Bulgaria Black Sea Scattered volcanics (Pliocene-Quaternary) East Macedonia-Thrace province (Upper Eocene-Oligocene)

Albania Thessaloniki 40 o Scattered volcanics North Aegean province (Pliocene-Quaternary) (Lower Miocene) Aegean Sea Greece Central Aegean province (Mid-Miocene) Athens East Aegean province Ionian Sea (Upper Miocene-Pliocene)

South Aegean Volcanic province (Pliocene-Quaternary) 35 o

Mediterranean Sea

050100 150 km 20o 25o 29o

Figure 4. Caenozoic volcanic provinces in Greece. The classification is based on geotectonic setting, composition and age of volcanic rocks. NATF, North Anatolian (modified from Vougioukalakis 2002, Fig. 3.1, p.64).

intraplate geochemical affinity, although some alkaline rocks. Sodic-alkaline basalt is the arc-related signatures are recognised at Etna and dominant rock type of Upper Miocene and Ustica (Cristofolini et al. 1987). Pliocene volcanicity. Upper Miocene trachytic rocks occur as lava flows and domes, as well as Caenozoic volcanism in Greece pyroclastic rocks, and range from shoshonite to rhyolite. Geochemically, they have higher total In Greece, five volcanic provinces are alkalis than similar rocks of the Scattered distinguished (Pe-Piper and Piper 2002, volcanics province of north-central Greece. Vougioukalakis 2002), based on age, setting and South Aegean (Pliocene-Quaternary) volcanic composition, as well as a scattered volcanics arc province extends from the Greek mainland to province (Figure 4). the islands south of Athens, through the south- The East Macedonia-Thrace province (Upper central Aegean to the far eastern part of the Eocene to Oligocene), comprises lava domes and Aegean Sea. It includes the famous of flows, and extensive large ignimbrite sheets, with Santorini, which is still active. The explosive a trend in K2O enrichment as the volcanicity eruption of this volcano in c.1500 BC is thought migrated southwards. Calc-alkaline to shoshonitic to have been of similar intensity to that of volcanic rocks consist of intermediate to high-K Krakatoa (Indonesia) in 1883 AD, with the felsic rocks, typical of the orogenic series of volcanic ash found in coastal sites as far away as active continental margins. Basalt is absent, and Israel and . The calc-alkaline rocks are the most mafic rock is basaltic andesite. typical of island arcs, and range in composition The North Aegean (Lower Miocene) province from basalt to rhyolite. comprises mainly of intermediate calc-alkaline to The Scattered (Pliocene-Quaternary) volcanics shoshonitic volcanic rocks, typical of active are similar in age to those of the South Aegean continental subduction belts, except that they are volcanic arc province, but have a different overall lower in MgO. geotectonic setting and composition, which is Central Aegean (Mid-Miocene) province, similar to the rocks of the Italian Roman province. comprising of high Mg-andesite, shoshonite and They are found in northern-central Macedonia and K-alkaline rocks occurring at small monogenic central-eastern Greece. Their composition ranges centres (lava domes), which are postulated to be from high potassium calc-alkaline to mafic associated with a between the shoshonitic rocks, with sodic alkaline basalt of Aegean microplate and the . Quaternary age locally. The central-eastern Greek East Aegean (Upper Miocene to Pliocene) volcanics are located on the Aegean extension of province occupies the eastern Aegean, where the the North Anatolian Transform Fault zone. volcanic rocks range from K-Na to K- and Na-

Superficial Deposits

Geologically recent deposits, often referred to most terrestrial evidence for the majority of some as Superficial deposits or ‘Drift’, cover most of 25 such glacial cycles, recognised in marine Europe. They range from soils and weathered sediments, has been destroyed by subsequent bedrock to sediments of fluvial, lacustrine, glacial, events. The surviving geomorphological and aeolian, coastal, estuarine and marsh origin, stratigraphical record is usually restricted to thought to be deposited during the last 2.4 Ma – deposits of the main glacial events, which each the Quaternary Period. This is the latest period of had particular geographical limits (see Figure 5). the Caenozoic Era, and comprises two grossly During intervening warm episodes (interglacials), unequal epochs, namely the Plio-Pleistocene (2.4 when temperatures not unlike those of the present Ma to 10 ka BP) and the (10 ka BP to day prevailed, ice sheets retreated or disappeared, the present day). leaving characteristic depositional landforms and The Quaternary Period was distinctively a time interglacial sediments. of frequent and marked climatic oscillations, European glacial advances generally spread where the colder periods exhibited mean annual outwards from the Fennoscandian shield. These air temperatures well below 0˚C. Unfortunately, were thick ice sheets, which, as they expanded,

locked away large amounts of water so that global continental shelf (now about 90 m below sea sea level fell, and land bridges appeared, linking level). most major land areas and present-day islands, In the Fennoscandian heartland, glacial into a single continental land mass. At the last scouring cut deep valleys and laid down thick, glacial maximum, when the centre of the often complex, interbedded sequences of clay, Weichselian ice-sheet was an estimated 2.5 km boulders, sand and gravel and wind-blown sand thick, sea level fell by over 120 m exposing the and dust (loess). In front of the advancing ice

Figure 5. Maximum extent of the European ice sheets: the Weichselian Glaciation, the Warthe phase of the Saalian Glaciation, the Saalian Glaciation, and the Elsterian Glaciation (from Anderson and Borns 1997, and Plant et al., 2003, Fig. 3, p.B230).

sheets, major rivers were diverted, dammed to (after about 1 Ma BP) increased anthropogenic form lakes, river terraces were cut and new disturbance of the environment. Furthermore, drainage catchments created. Across vast relieved of the weight of land ice, the continental distances, beyond the ice front, seasonally masses slowly rebounded, whilst global sea level catastrophic melt-water floods, created extensive rose with the release of water formerly locked up outwash (sandbars) of gravel, sand and silt. in ice, and marine, climate-influencing cold and Over this ground, which extended to the present- warm currents, shifted direction. day Mediterranean and beyond, periglacial These responses, after the last glacial maxima, conditions prevailed, in which cold, but non- resulted in the European coastal complex of glacial processes, such as loess deposition, slope ‘drowned’ fjord coastlines, raised beaches and the debris flow (solifluction), karst development and formation of the Irish Sea, the present North Sea soil mixing processes (cryopedogenesis), and the . produced distinctive landforms and sediments. After the last glacial maxima, the present day During interglacial periods, ice melt and distribution of land and sea was established across glacial recession led to increased river flow and Europe, with the development of the Irish and aggradation, the re-establishment of forests and North Seas and English Channel. In some cases,

Figure 6. Quaternary domains in Europe (from Plant et al., 2003, Fig. 2, p.B230).

drowned fjords and coastlines formed and as the Alps, the and the Caucasus elsewhere revised beaches. Bolshoy Kavkaz range, formed upland glacial At the onset of the Quaternary, the pre-glacial centres that locally modified this European had an existing drainage network, setting. distributing sediments within catchments, which An interpretation of the geochemical data in north- drained into the proto presented in this atlas should take into account North Sea basin. During ice advances, notably two important considerations: from the Fennoscandian region southwards, this Firstly, Quaternary deposits cover much of early fluvial imprint was modified or obliterated ‘lowland’ Europe mostly obscuring bedrock and new drainage networks were established. geology, and that these deposits were in part These networks, together with ice transportation, created by, and certainly transported by, glacio- redistributed pre-existing fluvial deposits and fluvial and aeolian processes. The consequence of mixed them with ‘northern’ sourced material – the this complex erosional and depositional genesis, is combined glacial, fluvial and Aeolian agencies, that material from localised mineral sources is transporting this material southward. Finally, highly likely to be dispersed in the direction of net since the last glacial phase to the present-day, resultant transportation, giving elongate many of the pre-glacial river courses have been geochemical signature anomalies that extend for re-established, recycling the deposits yet again. considerable distances away from the source area, This chaotic distribution of sediments, and potentially ‘smearing’ geochemical features resulting from a range of Quaternary, climate- for considerable distances away from the source determined processes, may be geographically area. delimited into four, very broad domains (Figure The second, and perhaps most important factor 6). Essentially, the Fennoscandian region to consider, is human changes to the environment underwent a net loss of material by glacial as humans migrated northwards across Europe as scouring, whilst much of northwest and central the climate improved. Subsequently, social Europe, south to 50oN, experienced a net gain of a development following the mastery of fire, the complex suite of clays, rock rubble, sand and development of settled agriculture, which has gravel and loess. South of this latitude, towards become gradually industrialised, together with the present-day Mediterranean, fluvial outwash industrialisation and urbanisation, have sediments and loess, blanket the underlying pre- increasingly polluted the environment, leaving a Quaternary strata. Regionally high ground, such significant anthropogenic geochemical imprint.

Acknowledgements

Alf Whittaker acknowledges his association the work was finished with the help of BGS over many years (1975-86) as UK National colleagues under the aegis of Ian Penn and Steve Correspondent for the International Geological Booth, who wrote the Quaternary section, and Correlation Programme (IGCP) Project No. 86 John Mendum contributed the section on the ‘The South-West Border Zone of the East Lewisian rocks of Scotland, as well as making European Platform’ led by Professor K.B. Jubitz many other editorial suggestions. George (Germany), Professor J. Znosko (Poland) and Dr Vougioukalakis, IGME volcanologist, is thanked D. Franke (Germany). Many of the maps and for his help in the compilation of the Tertiary- explanations produced during this UNESCO Quaternary volcanism in Greece. In addition, and international collaboration project have been used equally importantly, extensive use and reference in the preparation of the account. has been made to, and some abstraction from, the Dr Whittaker’s unfortunate illness prevented maps and accounts listed below. him from completing his sections of the text, but

References

Adams, F.D., 1954. The birth and development of the Mantle plumes, movement of the European plate, geological sciences. Dover Publications, Inc., New and polar wandering. Nature, 239, 82-86. York, 506 pp. Grünthal, G., Bosse, C., Sellami, S., Mayer-Rosa, D. & Ager, D.V., 1975. The geological evolution of Europe. D. Giardini, 1999. Compilation of the GSHAP Proceedings of the Geological Association, 86 (2), regional seismic hazard for Europe, Africa and the 127-154. Middle East. Global Seismic Hazard Assessment Ager, D.V., 1980. The . McGraw- Program (http://seismo.ethz.ch/gshap). Paper at: Hill, Maidenhead, U.K., 554 pp. http://seismo.ethz.ch/GSHAP/eu-af-me/euraf.html). Anderson, B.G. & Borns, H.W., 1997. The Ice Age Guidoboni, E., Comastri, A. & Traina, G., 1994. World. Scandinavian University Press, 208 pp. Catalogue of ancient earthquakes in the Asch, K., 2003. The 1:5 Million International Mediterranean area up to 10th century. Instituto Geological Map of Europe and Adjacent Areas: Nazionale di Geofisica, Rome, 504 pp. Development and Implementation of a GIS-enabled Horváth, F. & Berkhemer, H., 1982. Mediterranean Concept. Geologisches Jahrbuch; SA 3, BGR Back-arc Basins. In: H. Berkhemer and K. Hsü (Federal Institute for Geosciences and Natural (Eds.), Alpine-Mediterranean Geodynamics. Resources) Hannover; Schweitzerbart, Stuttgart, Geodyn. Ser., Am. Geophys. Union, Vol. 7, 141-173. Germany, 190 pp. +Digital map. Horváth, F. & Royden, L., 1981. Mechanism for the http://www.bgr.de/index.html?/karten/IGME5000/ig formation of the Intra-Carpathian Basins: a review. me5000.htm Earth Evolution Science 3-4, 307-316. Ayuso, R.A., De Vivo, B., Rolandi, G., Seal, R.R. & Horváth, F., Dövenyi, P., Szalay, A. & Royden, L.H., Paone, A., 1998. Geochemical and isotopic (Nd- 1988. Subsidence, thermal and maturation history of PbSr-O) variations bearing on the genesis of volcanic the Great Hungarian . In: L.H. Royden and F. rocks from Vesuvius, Italy. Journal of Volcanology Horváth (Eds.), The Pannonian Basin, a study in and Geothermal Research, 82, 53-78. Basin evolution. American Association of Petroleum Blundell, D., Freeman R. & Mueller, S. (Eds.), 1992. Geologists, Memoir, 45, 355-372. A Continent Revealed – The European Geotraverse. Horváth, F., Szalay, A. Dövenyi, P. & Rumpler, J., European Science Foundation. Cambridge 1986. Structural and thermal evolution of the University Press, Cambridge, 287 pp. Pannonian Basin: an overview. In: J. Burrus (Ed.), Brix, F., Kröll, A. & Wessely, G., 1977. Die Molasse- Thermal modelling in sedimentary basins. Edition zone und deren Untergrund in Niederösterreich. Technip, Paris. Collection Colloques et Séminaires, Erdöl-Erdgas-Z., Special Issue 93, 12-35. 44, 339-358. Choubert, G. & Faure-Muret, A. (General Co- Kröll, A., 1980. Das Wiener Becken. In: F. Brix and ordinators) 1976. Sheet 9 Europe. 1:10,000,000. O. Schultz (Eds.), Erdöl und Erdgas in Österreich. With explanatory note by G. Luettig and F. Delany. Naturhistorisches Museum, Wien, 147-179. Geological World Atlas. UNESCO and Commission Lexa, J. & Konečný, V., 1998. Geodynamic aspects of for the Geological Map of the World. the Neogene to Quaternary volcanism. In: M. Rakús Cristofolini, R., Menzies, M.A., Beccaluva, L. & (Ed.), Geodynamic development of the Western Tindle, A., 1987. Petrological notes on the 1983 Carpathians. Geological Survey of Slovak Republic, lavas at , Sicily, with reference to their Bratislava: 219-240. REE and Sr-Nd isotopic composition. Bulletin of Matte, P., 1991. Accretionary history and crustal Volcanology, 49, 599-607. evolution of the Variscan belt in Western Europe. De Vivo, B., Rolandi, G., Gans, P.B., Calvert, A., Tectonophysics, 196, 309-337. Bohrson, W.A., Spera, F.J. & Belkin, H.E., 2001. Peccerillo, A. & Panza, G., 1999. Upper mantle New constraints on the pyroclastic eruptive history domains beneath central-southern Italy: petrological, of the Campanian volcanic Plain (Italy). Mineralogy geochemical and geophysical constraints. Pure and and Petrology, 73, 47-65. Applied Geophysics, 156, 421-443. Drakos, A.G. & Stiros, S.K., 2001. The AD 365 Peccerillo, A., 2001a. Geochemistry and petrogenesis earthquake from legend to modelling. In: P.G. of Quaternary magmatism in central-southern Italy. Marinos, G. Tsiambaos, A. Alexopoulos, V. Geochemistry International, 39, 521-535. Tsapralis, Th. Rondoyanni and E. Moraiti (Editors), Peccerillo, A., 2001b. Geochemical similarities Proceedings of the 9th International Congress with between the Vesuvius, Phlegrean Fields and emphasis on the contribution of Geosciences to Stromboli volcanoes: petrogenetic, geodynamic and Development. Bulletin of the Geological Society of volcanological implications. Mineralogy and Greece, XXXIV (4), 1471-1424 (text in Greek with Petrology, 73, 93-105. an English abstract). Peccerillo, A., 2003. Plio-Quaternary magmatism in Duncan, R.A., Petersen, N. & Hargraves, R.B., 1972. Italy. Episodes, 26, 222-226.

Pe-Piper, G. & Piper, J.W., 2002. The igneous rocks of Semken, S. & Stegena, L., 1980. The formation of Greece: The anatomy of an orogen. E. the the Intra-Carpathian Basin as determined from Schweizerbart, Borntraeger, Cramer, Science subsidence data. Earth Planetary Science Letters 51, Publishers, Stuttgart, 573 pp. 139-162. Plant, J.A., Reeder, S., Salminen, R., Smith, D.B., Stegena, L. & Horváth, F., 1982. Review of the Tarvainen, T., De Vivo, B. & Petterson, M.G., 2003. Pannonian Basin. In: F. Horváth (Ed.), Evolution of The distribution of uranium over Europe: geological extensional basins within regions of compression, and environmental significance. Transactions of the. with emphasis on the Intra-Carpathians. Eötvös Institution of Mining and Metallurgy, Section B, 112 University, Budapest Publication, 19-25. (3), 221-238. Stoppa, F. & Wholley, A.R., 1997. The Italian Póka, T., 1988. Neogene and Quaternary volcanism of carbonatites: field occurrence, petrology and regional the Carpathian-Pannonian region: changes in significance. Mineralogy and Petrology, 59, 43-67. chemical composition and its relationship to basin Vougioukalakis, G.E., 2002. Petrological, geochemical formation. In: L.H. Royden and F. Horváth (Eds.), and volcanological study of the Almopia Pliocene The Pannonian Basin, a study in Basin evolution. volcanic formations: Relationship with geothermal American Association of Petroleum Geologists, manifestations in the region. Unpublished Ph.D. Memoir 45, 257-277. thesis (in Greek with an English summary), Aristotle Rey, P., Burg, J.-P. & Casey, M., 1997. The University, School of Geology, Thessaloniki, Scandinavian Caledonides and theirrelationship to Greece, 303 pp. the Variscan belt. In: J.-P. Burg and M. Ford (Eds.), Wessely, G., 1987. Mesozoic and Tertiary evolution of Orogeny Through Time. Geological Society of the Alpine-Carpathian foreland in eastern Austria. London, Special Publication 121, 179-200. Tectonophysics, 137, 45-59. Royden, L. and Horváth, F. (Eds.), 1988. The Windley, B., 1992. Tectonic evolution of Europe: Pannonian Basin, a study in basin evolution. Precambrian Europe. In: D. Blundell, R. Freeman American Association of Petroleum Geologists, and S. Mueller (Eds.), A Continent Revealed: The Memoir 4, 394 pp. European Geotraverse, Cambridge University Press, Royden, L., 1988. Late Caenozoic tectonics of the Cambridge, 139-152. Pannonian basin system. In: L.H. Royden and F. Windley, B.F., 1995. The evolving continents. London, Horváth (Eds.), The Pannonian Basin, a study in Wiley, 526 pp. Basin evolution. American Association of Petroleum Ziegler, P.A., 1988. Laurussia-Old Red Continent. In: Geologists, Memoir 45, 27-48. N.J. McMillan, A.F. Embry and D.J. Glass (Eds.), Royden, L., Horváth, F. & Burchfiel, B.C., 1982. Devonian of the World. Canadian Society of Transform faulting, extension and subduction in the Petroleum Geologists, Memoir 14 (1), 15-48. Carpathian Pannonian region. Geological Society of Ziegler, P.A., 1990. Geological Atlas of Western and America, Bulletin 93, 717-725. Central Europe. Shell International Petroleum Sclater, J.G., Royden, L., Horváth, F., Burchfiel, B.C., Maatschappij B.V., 232 pp.