Rahl200432nd IGC IGC Guidebook B32 Exhumation of High-Pressure Metamorphic Rocks Within an Active Convergent Margin Crete

Home , Agia Roumeli, Ha Gorge, Miamou, Palaiochora, Rethymno, Sea of Crete

B32_copertina_R_OK C August 20-28, 2004 20-28, August Florence - Italy - Florence

Field Trip Guide Book - B32 Pre-Congress M.T.Fassoulas, C. Brandon Leaders: Associate Rahl J.M. Leaders: MARGIN, CRETE,GREECE AN ACTIVECONVERGENT METAMORPHIC ROCKSWITHIN HIGH-PRESSURE EXHUMATION OF 32 Volume n° 2 - from B16 to B33 GEOLOGICAL CONGRESS GEOLOGICAL nd INTERNATIONAL B32 28-05-2004, 17:53:44 The scientific content of this guide is under the total responsibility of the Authors

Published by: APAT – Italian Agency for the Environmental Protection and Technical Services - Via Vitaliano Brancati, 48 - 00144 Roma - Italy

Series Editors: Luca Guerrieri, Irene Rischia and Leonello Serva (APAT, Roma)

English Desk-copy Editors: Paul Mazza (Università di Firenze), Jessica Ann Thonn (Università di Firenze), Nathalie Marléne Adams (Università di Firenze), Miriam Friedman (Università di Firenze), Kate Eadie (Freelance indipendent professional)

Field Trip Committee: Leonello Serva (APAT, Roma), Alessandro Michetti (Università dell’Insubria, Como), Giulio Pavia (Università di Torino), Raffaele Pignone (Servizio Geologico Regione Emilia-Romagna, Bologna) and Riccardo Polino (CNR, Torino)

Acknowledgments: The 32nd IGC Organizing Committee is grateful to Roberto Pompili and Elisa Brustia (APAT, Roma) for their collaboration in editing.

Graphic project: Full snc - Firenze

Layout and press: Lito Terrazzi srl - Firenze

B32_copertina_R_OK D 21-05-2004, 14:30:07 Volume n° 2 - from B16 to B33

32nd INTERNATIONAL GEOLOGICAL CONGRESS

EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE: A FIELD GUIDE

AUTHORS: J.M. Rahl1, C. Fassoulas2, M.T. Brandon1

1Yale University - U.S.A. 2 Natural History Museum of Crete - Greece

Florence - Italy August 20-28, 2004

Pre-Congress B32

B32_R_OK A 21-05-2004, 14:33:03 Front Cover: topography and bathymetry of the eastern Mediterranean

B32_R_OK B 21-05-2004, 14:33:07 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

Leader: J.M. Rahl Associate Leaders: C. Fassoulas, M.T. Brandon

Introduction airports, one in Irakleio and the other in Chania. Here, Subduction involves the horizontal convergence of and in the other major cities in Crete, it is possible to two tectonic plates; however, researchers have long rent a car or van. The localities described in the fi rst recognized that widespread extensional deformation three days of the fi eld guide are road cuts that are is a characteristic of many subduction zones (e.g., easily reached by automobile. The fourth day of the Royden, 1993). The Hellenic subduction zone is trip is a hike through the Samaria Gorge in western one such region of overall plate convergence and Crete. To pass the gorge, it is best to take a bus to the widespread horizontal extension (Figure 1). As the village of Omalos. Public buses depart from Chania lithosphere of the African plate dips to the north, and Palaiochora. After you hike down the gorge, you deformation in the overriding European plate has will arrive in the village of Agia Roumeli. Here you thinned the continental crust, forming the Aegean can purchase a ticket for a boat that will transport you Sea. Unlike in some subduction zones (e.g., Japan), to Chora Sfakion, from where buses will be available extension in the overriding plate is not restricted for transportation back to Chania or elsewhere. to the backarc region; thinned continental crust underlies the Sea of Crete outboard of the volcanic Field references: arc. Although most of the attenuated continental crust Several relevant fi eld guides have been published that is now submerged, the island of Crete provides a view describe the geology of central and western Crete. of extensional deformation in the forearc region. Field Guide to the Geology of Crete by Charalambos Crete exposes a variety of variably metamorphosed Fassoulas outlines 7 days of fi eld stops throughout all sedimentary and volcanic units juxtaposed by thrust of Crete. The book is intended for both the general faulting during the Oligocene and later thinned public and geologists, and is well-illustrated with by recent (and still active) normal faults. This many color photographs. Another fi eld guide has tectonic thinning has exhumed high pressure-low been written by Meulenkamp and others (1979), who temperature metamorphic rocks, which were only describe a 4 day trip that focuses on the Miocene recently metamorphosed (~20 Ma) at about 35 km sediments of western and central Crete. depth above the subducting slab. Thus, the island A good road map is essential for a fi eld trip to Crete, provides an excellent laboratory to study processes as many of the smaller roads in the interior of the and consequences of syn-convergent extension. island are unmarked and can be diffi cult to fi nd. We The goal of this fi eld excursion is to examine recommend the series of maps by produced by Road the tectonic evolution of Crete, including the Editions. deformational, metamorphic, thermal, and The most comprehensive geologic map has been exhumational history of the rocks. The four day trip compiled by Creutzberg et al. (1977). A series of will begin in Psiloritis Mountains of central Crete, more detailed maps has been drafted by the Institute where we will introduce the major tectonostratigraphic of Geological and Mining Exploration (IGME) of units, and inspect several exposures of the Cretan Greece. detachment fault. On the second day, we will examine the thermal and deformational history of the high- Regional tectonic setting pressure, low-temperature metamorphic rocks in Overview Crete. The third day will focus on the development The Mediterranean Sea represents a vestige of the of sedimentary basins in western Crete in response Tethyan Seaway, an east-west trending ocean basin to widespread late Miocene extension. The fourth formed during the breakup of the Pangea. Throughout n° 2 Volume - from B16 to B33 day will involve a hike through the deeply incised the Cenozoic, convergence between Eurasia and Samaria Gorge, which provides geomorphic evidence southern plates of Gondwana (including the African, of recent rapid uplift of a large footwall block Apulian, Arabian, and Indian plates) slowly consumed associated with active normal faulting along the south the Tethyan Seaway and led to the formation of side of Crete. the Alpine-Himalayan chain, an orogenic zone that extends for several thousand km from the Alps in Essential logistical information: southwestern Europe through the Middle East and Crete is very accessible. The island is serviced by two into the Himalaya.

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21-05-2004, 14:38:20 o . va

EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

Figure 2 - Cross section through the Cretan wedge, showing variation in topography and depth to the Moho. (Moho from T. Meier et al., unpublished results, 2003).

The Hellenic subduction zone is presently consuming forearc of the subduction system. North of the island, the remnants of Tethyan seafl oor, which is subducting the topography quickly drops off into the thinned northward beneath Crete as part the lithosphere of continental crust of the Cretan Sea (Figure 2) (Makris the African plate (Figures 1 and 2). Crete lies in the and Stobbe, 1984). About 100 km north of Crete lies forearc of the Hellenic Subduction Zone. Active the volcanic arc of the Hellenic Subduction Zone, subduction is indicated by a north-dipping Wadati- represented by the island of Santorini. Like in the Benioff seismic zone extending beneath Crete to Sea of Crete, the crust in the back-arc of the system is a depth of about 200 km (Le Pichon and Angelier, also attenuated continental crust (McKenzie, 1978; Le 1979; Knapmeyer and Harjies, 2000). Tomographic Pichon and Angelier, 1981). North of Santorini, the studies show that this seismicity corresponds to a cold various islands of the Cyclades expose mid- to lower- lithospheric slab that extends through the transition crustal metamorphic and igneous rocks exhumed zone and into the lower mantle below Europe to the surface along low-angle detachment faults (Spakman et al., 1988). At the longitude of Crete, (Lister et al., 1984). The exposure of high-pressure the subduction front in this system is located about metamorphic rocks in the Aegean Sea is one line of 200 km south of the island, just north of the coast of evidence that the crust there has been thinned through Libya (Kastens, 1991; Kopf et al., 2003) (Figures 1 extensional faulting (Lister et al., 1984; Buick, 1991). and 2). Sediments from the downgoing plate have This conclusion is confi rmed by seismic refl ection accumulated in the Mediterranean Ridge complex, a studies which demonstrate a crustal thickness of 20 broad accretionary wedge positioned between Africa to 25 km (e.g., Makris, 1978; Makris and Stobbe, and Crete. Kopf et al. (2003) estimate an accretionary 1984). fl ux of > 17 km2/myr. Between Crete and the crest of the Mediterranean ridge are a series of east- and Global Positioning System (GPS) studies have northeast-trending depressions or troughs (e.g., provided a detailed view of the modern tectonic Hellenic, South Cretan, Pliny, Strabo in Figure 1b). motions in the eastern Mediterranean (e.g., Early papers considered that these depressions might McCluskey et al., 2000) (Figure 3). In this region, one be the active subduction zone, but subsequent work important feature shown by the velocity fi eld is the n° 2 Volume - from B16 to B33 has shown that the front of the subduction wedge lies westward migration of the Anatolian block towards along the southern margin of the Mediterranean Ridge the Aegean Sea along the right-lateral North Anatolian (Kastens, 1991). Some authors have suggested that fault in northern Turkey. This movement is driven by these troughs might mark sinistral strike-slip faults the ongoing collision between the Arabian block and associated with the tectonic escape of Turkey (e.g., Eurasia, with Turkey “escaping” as a coherent block Huguen et al., 2001), although direct evidence for the to the west (McKenzie, 1972). Escape is though to formation of these troughs is lacking. start sometime between 12 Ma and 4 Ma (McCluskey Crete itself is positioned as an emergent high in the et al., 2000). The extrusion of the Anatolian block

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Sometime since the Miocene, southward migration of related to a “pull” from the subduction zone rather the margin near Crete led to the development of the than a “push” from Turkey. curvature of the Hellenic arc. Le Pichon and Angelier A second idea is that the southward motion of Crete (1979) argue that the southward migration was related and the formation of the Aegean Sea is related to to the initiation of subduction in the region, which gravitational collapse of an orogenic topography they believed occurred at 13 Ma because of the (Dewey, 1988). The argument is that convergence depth of active seismicity. However, the realization during the Oligocene led to stacking of thrust nappes that subduction operated for a much longer time and thickening of continental crust. Subsequent (Spakman et al., 1988) has forced a re-evaluation of thermal relaxation lead to gravitational spreading of the timing constraints for the southward migration of the thicken zone. However, as noted by Thomson et the Hellenic arc (see discussion in the Appendix of al. (1999), there is no evidence for extremely thick Kastens (1991)). Paleomagnetic results (Kissel and continental crust in the Oligocene. Laj, 1988; Duermeijer et al., 1998; Duermeijer et A third idea is that extension in the Aegean Sea is al., 2000) show that block rotations in the Hellenic related to rollback of the African plate (Le Pichon and arc were acquired mainly after 5 Ma, suggesting that Angelier, 1979). Meulenkamp et al. (1988) showed the formation of the curvature of the Hellenic arc has that subduction had been well-established prior to developed since that time as well. the formation of the curvature of the Hellenic Arc. The southward migration of Crete appears to be They argue that abundant Miocene deformation in related to the extension occurring above the Hellenic Crete is coincident with the initiation of the rollback subduction zone. North of Crete, the crust beneath the process. Although tomographic results indicate that Sea of Crete and the Aegean Sea is continental and the slab is continuous to great depths (in excess of typically 20-25 km thick (Makris and Stobbe, 1984). 600 km) at the longitude of Crete, a continuous slab Prior to deformation, the crust of the Aegean Sea has has not been successfully imaged to the west beneath been estimated to be 1.5 to 2 times thicker than the mainland Greece (Spakman et al., 1988; Wortel and current thickness (McKenzie, 1978; Angelier et al., Spakman, 2000). These observations have to the 1982). hypothesis that the descending slab is torn beneath How can widespread extension occur in regions Greece, forcing the still continuous segment beneath of overall tectonic convergence? Several tectonic Crete to support the entire load of the downgoing slab. processes have been proposed to account for the The concentration of the slab-pull force beneath Crete southward migration of Crete and the formation of then drives rapid rollback as the African lithosphere the Aegean Sea. One idea focuses on the “Anatolian sinks deeper into the mantle (Wortel and Spakman, push” associated with the westward escape of Turkey 2000). The importance of rollback in controlling into the Aegean. The motion of the Anatolian block the tectonics of the eastern Mediterranean has been is proposed to be transmitted to the continental crust emphasized in fi nite-element simulations of the of the Aegean region which then spreads and extends region, both for the Aegean Sea (Meijer and Wortel, southward, causing southward migration of the 1997; ten Veen and Meijer, 1998) and also on the Hellenic subduction zone (Hatzfeld et al., 1997). This scale of the entire Mediterranean (Jiménez-Munt southward motion is sometimes described as overfl ow et al., 2003). In fact, Jiménez-Munt et al. (2003) of the Aegean over the African plate. However, recent conclude that it is not possible to match the observed investigations suggest that the “Anatolian push” is geodetic measurements in the Mediterranean without probably of secondary importance in controlling the deep subduction and rapid rollback in the Hellenic formation of the Aegean Sea. For example, using a Subduction Zone. fi nite element model Meijer and Wortel (1997) found that the force applied to the Aegean by the Anatolian Geology of Crete n° 2 Volume - from B16 to B33 block had to be small to get a match to the modern Most of the geologic units exposed on Crete were velocity fi eld. The GPS results of McCluskey et al. initially assembled by thrust imbrication during the (2000) also suggest that the westward motion of Oligocene (Creutzberg and Seidel, 1975; Bonneau, Turkey does not strongly infl uence the southward 1984; Hall et al., 1984). That initial sequence was motion of Crete. As described above, the divergence thinned dramatically by normal faulting, starting at between Europe and the Aegean Sea is accommodated ~15 Ma and continuing to the present (Thomson et in a zone in the northern Aegean. Thus, extension al., 1998, 1999). Even so, the original nappe sequence across the southern Aegean and Crete appears to be formed during Oligocene thrusting is still readily

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which in increasing structural position are: 1) the sub- (called Ida nappe by some), which is made up detachment nappes, 2) the supra-detachment nappes, entirely of the Plattenkalk Group. The Plattenkalk and 3) syn-extensional sediments. The sub-detachment Group is commonly overturned, and large recumbent nappes are defi ned by a common high pressure-low folds are found in some areas. Nonetheless, the temperature (HP-LT) metamorphic history, imposed unit maintains a coherent well defi ned internal in Oligocene and early Miocene time, shortly after stratigraphy consisting of stromatolitic dolomite, accretion at the Hellenic subduction zone. The carbonate breccia, and a distinctive sequence of stratigraphic units involved are the Plattenkalk, platy, well-bedded carbonates with chert interbeds Trypali, and Phyllite-Quartzite (defi ned below), (Epting et al., 1972; Seidel et al., 1982; Hall and which consist mainly of carbonates, schists, and Audley-Charles, 1983; Krahl et al., 1988). The oldest quartzites that span in age from Late Carboniferous to Plattenkalk consists of shallow marine carbonates Oligocene. This metamorphosed tectonic assemblage with Permian fusilinids (Bonneau, 1984). Younger is bounded at its top by a one or more low-angle parts of the section consist of carbonates and cherts normal faults, which are collectively referred to as the that record a transition to deeper water conditions. Cretan detachment. It is also important to note that the The thickness of the Plattenkalk is debated, with stratigraphic units that make up the HP-LT footwall estimates ranging from 1 and 2.5 km (compare Epting of the Cretan detachment are never found above that et al., 1972 and Hall and Audley-Charles, 1983). The structural level. Plattenkalk is devoid of siliciclastic input except for a The supra-detachment nappes are pre-Miocene thin, 10 – 30 m layer of fl ysch at the top of the section. accretionary units that lie above the Cretan In central Crete, foraminifera from this fl ysch have detachment. Like the sub-detachment nappes, been dated by Bizon et al. (1976) as Oligocene (29.3 this structural assemblage also shows evidence of to 28.3 Ma). The Plattenkalk is thought to represent Oligocene accretion and thrust imbrication, but it the sedimentary cover of the southern margin of the contrast it always remained structurally shallow after Adria continental block (sometimes referred to as the accretion, as indicated by the absence of Cenozoic Apulia block), which presently underlies the modern HP-LT metamorphism. The stratigraphic units within Adriatic Sea. The Adria block is being overridden to the supra-detachment napes include the Tripolitza, west by the Apennine thrust belt and to the east by Pindos, and Uppermost units. They are dominated the Dinarides and Hellenides of the western Balkans by carbonates, ophiolitic rocks, and some siliciclastic and Greece. It also continues northward into the turbidites, with ages spanning from Triassic to Alps, where it forms the highest structural unit in that Eocene. Alpine collision zone. The syn-extensional sediments correspond to a series Bonneau (1984) correlated the Plattenkalk Group of high level sedimentary basins, ranging from middle with the carbonates of the Ionian Zone of western Miocene to present in age. These basins are intimately mainland Greece. The Plattenkalk is thought associated with late Cenozoic normal faulting in to be a fully allochthonous nappe. Although its Crete. They provide a detailed record of unroofi ng of base is not observed on Crete, the presence of an the Cretan nappe sequence, and the emergence of the active subduction zone beneath Crete supports the mountainous subaerial topography associated with interpretation that it is an accreted tectonic slice. modern Crete. Furthermore, to the east in Rhodes, the Plattenkalk is found overthrust on a more inboard carbonate We provide a more detailed review below of Cretan platform, associated with the “pre-Apulian domain” geology, with the discussion moving from the from mainland Greece (Bonneau, 1984). structurally lowest rocks below the Cretan detachment Trypali Nappe. In western Crete, the Plattenkalk upward to the Late Cenozoic extensional basins. We nappe is structurally overlain by a small nappe n° 2 Volume - from B16 to B33 follow the practice of dividing the nappes in Crete made up entirely of the Trypali Formation, which according to their internal stratigraphy and referring consists of well bedded dolomite, with peloidal to each nappe using the name of the dominant mudstone and detrital carbonate layers (Creutzburg stratigraphic unit in the nappe. and Seidel, 1975). The age of the Trypali has been reported as upper Triassic (Karakitsios, 1987) The sub-detachment nappes or lower Jurassic (Kopp and Ott, 1977). These Plattenkalk nappe. The structurally lowest unit sediments were deposited primarily in peritidal exposed on Crete is the Plattenkalk (PK) nappe depositional environments, including sabhkas, tidal

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: is an abundance of brecciated horizons, interpreted to interpreted horizons, abundancebrecciated an of is Karakitsios, 2002). A distinctive feature of the Trypali fl is dominated by fl by dominated is al., Tripolitza the et Eocene, to Paleocene the (Hall From 1984). turbidites siliciclastic eventually and calciturbidtes into upwards grade carbonates marine shallowthese section, up Higher Greece. mainland in 1976), Seidel, and which are thought to be equivalent with the Tyros Triassicunit (Sannemann the are beds section Ravdoucha the Bonneau, of base 1975; the At Seidel, 1984). and mainland (Creutzberg in upper Greece sequence to platform Triassic carbonate the Eocene with correlated are Pindos overlying the and Tripolitza The Eocene. middle the and Triassic Late platform the between deposited marine carbonates shallow-water of consists Group Tripolitza The nappe). Gavrovo the as known (also nappe Tripolitza the of carbonates shallow-water are Tripolitzanappe. The supra-detachment nappes. (Theye andSeidel,1991). Crete on as position structural similar a occupies it throughout where Peloponnesus, southern found the in is also and PQ Crete The PQ 1983). the al., of et rocks (Krahl sedimentary the for age Triassic defi Conodonts (i.e. basement Hercynian 1982). al., et (Seidel Paleozoicrocks) upper granitoid of slices includes sequence also the Crete, eastern In 1983). al., et (Krahl rocks volcanic and gypsum, limestone, minor with sediments, siliciclastic quartz-rich by dominated is Crete, group. throughout widespread (PQ) is which Phyllite-Quartzite nappe, This the of up made is nappe. Phyllite-Quartzite karst weatheringduringthelateQuaternary. and of the Trypali are a recent feature formed by subaerial Pomoni-Papaioannou breccias carbonate the et that argue Recently, (2002) Karakitsios (Thomson Oligocene 1999). to al., Eocene the in rocks Plattenkalk the of subduction before shortly foreland carbonate platform (Hall et al., 1984) or fl Plattenkalk the of collapse Jurassic Early an during represent submarine fault scarp breccias formed either f h ui ae ae rasc Lk te Plattenkalk the Like Triassic. Late are unit the of parts oldest These calc-breccias. and calciturbidites, radiolarites, limestones, pelagic including sediments, water deep by characterized is Pindos The contact. structurally sequence, overlying the Tripolitza in thrust nappe. Pindos from theoverriding Eurasianplate(Halletal.,1984). ats,hypersaline lagoons (Pomoni-Papaioannou and h Pno npe s h nx i the in next the is nappe Pindos The n a ae abnfru t te Late the to Carboniferous Late a ne Above the Phyllite-Quartzite nappe Phyllite-Quartzite the Above ysch deposits thought to be derivedbe to thought deposits ysch h nx hget nappe highest next The exure of the contrast, Hall et al. (1984) consider the various rocks various the consider (1984) al. et Hall contrast, In nappes. thrust mappable and individual as nappe Uppermost the of subunits various the regard 1975) Seidel, Creutzburgand 1984; Bonneau, (e.g., authors ocean, as well as the overriding European plate. Some Pindos Cretaceous 1976; to Jurassic the both al., from derived et (Seidel be to thought are rocks These 1998). al., serpentinite et Thomson mainly of cap ophiolitic an and leucogranites, schists, amphibolites, pillow basalts, gabbros, deep water marine sediments, oceanic including unit, UM the in present are types 1976). al., et (Seidel Miocene the in varietyA rock of metamorphism for evidence no contain they Jurassic, the than older are nappe Uppermost the of rocks the Although nappe. Uppermost the into grouped been have that rocks of series diverse a are nappe Pindos Uppermost nappe. the Adria microcontinent(Robertsonetal.,1991). of margin northern the along formed that basin deep a be to interpreted is Pindos Greece. The mainland in exposed sequence Olonos-Pindos the with Crete on nappe Pindos the correlates (1984) Bonneau and shales. sandstones turbidite Eocene capped to also Paleocene is a by unit Pindos the Tripolitza, the and ru sdmns r dpstd n h eei Group, Tefeli the Vrysses on deposited are intercalations. sediments group gypsiferous contain the marls places, In marls. and shallow-marine laminated homogenous, of alternations of the equivalent lateral constitute which limestones reefal, commonly GroupVrysses environments marine and brackish, fresh-water, in deposited were and clays sediments sands, These conglomerates, predominantly rocks. are basement or group Prina the of sediments the either on deposited formations TefeliGroup marine environments. shallow or brackish to non-marine in deposited were well- sediments These matrix. calcareous a a with cemented have generally that breccioconglomerates Group. Prina recognizable over allofCrete. Serravallian. the Crete into six groups of formations, most of of which are sediments the in divided (1979) the al. et beginning Meulenkamp since Crete likely on Miocene, occurred has Sedimentation Syn-Extensional Sediments Pindos units. the of part upper the in olistostrome major a forms the UM unit as large blocks in a “Blocky Flysch” that (e.g., the Arvi, Miamou, Vatos, Asteroussia nappes) of . “Non-consolidated” terrige-nous clastic terrige-nous “Non-consolidated” . . This group is composed of bioclastic, of composed is group . This ak ietn beca and breccias limestone Dark Tectonically above the rocks of the 21-05-2004, 14:35:31 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

pre-Neogene basement, and occasionally the Prina The upper units lack evidence of Miocene HP/LT Group. metamorphism. No high-pressure metamorphic minerals have been described from the Tripolitza Hellenikon Group. and Pindos units, and the few metamorphic rocks Reddish, fl uvio-lacustrine conglomerates, and in the UM unit are related to an older period of occasional brackish and lagoonal deposits metamorphism and deformation (Seidel et al., 1976). with gypsum. The Hellenikon conglomerates Furthermore, Thomson et al. (1998) showed using unconformably overlie the Vrysses Group, older apatite fi ssion-track ages that most of the UM unit has Neogene strata, and locally pre-Neogene basement. been cooler than 120°C since 30 Ma. Finikia Group. Open marine marls and clays which commonly display laminated and locally siliceous The Cretan Detachment Fault and exhumation of the interbeds. At many places the base of the Finikia high pressure rocks Group is formed by a marl breccia. These sediments The juxtaposition of the HP-LT metamorphic rocks of overlie the Hellenikon Group or the Vrysses Group. the PQ unit with the unmetamorphosed rocks of the Agia Galini Group. Coarse, generally reddish, non- overlying Tripolitza unit has been taken as evidence marine conglomerates and sands that overlie (and for a signifi cant normal fault, the Cretan Detachment are in part the lateral equivalent of) sediments of the (Fassoulas et al., 1994; Jolivet et al., 1996; Thomson Finikia Group. These represent the youngest Neogene et al., 1999). This fault, active in the Miocene, has rocks on Crete. cut out 20 to 25 km of structural section and is Undifferentiated Pleistocene. No formal subdivisions estimated to account for 85 to 90% of the exhumation have been made. These marine terraces and experienced by the lower plate rocks (Thomson et al., continental deposits unconformably overlie Neogene 1999). or pre-Neogene rocks. The geographic extent of the sub-detachment and supra-detachment units is shown in Figure 5. It is Metamorphic conditions important to note that the original Cretan detachment The sub-detachment nappes contain clear evidence has been extensively dismembered by younger of HP-LT metamorphism. The Plattenkalk nappe normal faults. Nonetheless, the offsets on the younger is composed mainly of lithologies unsuitable for faults are generally a kilometer or less, whereas the thermobarometric work. Even so, a metabauxite Cretan detachment seems to have cut out about 25 to horizon near the stratigraphic base of the Plattenkalk 30 km of the Cretan nappe sequence. As a result, the in central Crete contains lawsonite, magnesio- map scale view shown in Figure 5 probably provides carpholite, pyrophyllite and diaspore. Theye et al. a reasonable view of the original distribution of (1992) estimate maximum P-T conditions of about the sub-detachment and supra-detachment units at 1 GPa and 350°C. HP-LT metamorphic assemblages the scale of Crete. Some authors have argued that are more commonly found in the Phyllite-Quartzite the Cretan detachment formed with a consistent nappe. Diagnostic minerals include carpholite, sense of motion, interpreted as top-S by Lister et chloritoid, sudoite, phengite, aragonite, and jadeitic al. (1984) or top-N by Jolivet et al. (1996). With pyroxene. Seidel et al. (1982) and Theye and Seidel these interpretations in mind, note that the supra- (1991) estimate that exposed rocks in Crete show detachment units are exposed both north and south an increasing metamorphic grade from 0.6 GPa and of the island. Thus, there is no evidence on Crete of a 300°C in eastern Crete to 1.0 GPa and 400°C in top-N or top-S break-away zone. These features could western Crete. be located offshore to the north or south. However, as This HP-LT metamorphism must be late Cenozoic in an alternative, we suggest that the Cretan detachment age since it involves Eocene and Oligocene turbidites might have formed by slip between a coaxially n° 2 Volume - from B16 to B33 in the Plattenkalk and Phyllite-Quartzite napes. K-Ar extending hangingwall (see Fassoulas et al., 1994; and Ar-Ar dating of metamorphic white mica gives Fassoulas, 1999, for a similar coaxial interpretation). isotopic ages of 21 to 24 Ma (e.g., Jolivet et al., In this case, the sub-detachment nappes would have 1996). We interpret these ages as recording the time of punched upward through the supra-detachment growth of the metamorphic white mica, given that the nappes, resulting in a variety of shear-sense directions maximum temperatures during metamorphism were on the detachment. probably less than the partial retention temperatures for white mica (~400°C). Thomson et al. (1999) provide a concise review of the

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: pit e t te omto o wdsra basins widespread of formation the block to renewed led uplift Messinian, the of during period a subsidence After 1979). al., et difﬁ these (Meulenkamp and date but unfossiliferous Serravallian, typically be are units to thought are these of basins oldest The 1999a). Postma, and Veen ten 1983; Peters, and Fortuin 1979; al., et Meulenkamp (e.g., Crete development throughout basins the sedimentary many to of led Miocene the in Extension nannoplankton (calcareous biozone NN10)(FrydasandKeupp, 1996). Ma 9 about by surface PQ indicate the lower plate rocks were exposed at the of clasts contain that deposits Conglomeratic Ma. 10 that the lower plate rocks cooled below 210°C around ages show prep) in al., (U-Th)/He et (Rahl Reiners Peter Zircon by obtained 2002). about al., at et (Brix 240°C Ma through 18 cooling show data track were achieved between 21 and 24 Ma. Zircon ﬁ conditions P-T peak show and growth metamorphic record Ma. 1996) al., 36 et (Jolivet ages and Ar/Ar mica 32 White between subducted units were tectonic Crete HP-LT in the Plattenkalk of that top demonstrate the Series these at in of sediments The Oligocene evolution 7. Figure in summarized thermal are rocks plate lower the for constraints thermochronologic and stratigraphic The 6). (Figure Crete in rocks sub-detachment the P-T-tof evolution levels duringtheOligocene.TheNeogenesedimentsareshown inwhite. by OligoceneHP-LT metamorphism,andthe supra-detachment nappes(inlightgrey),which were atshallow crustal Figure 5-Tectonic mapshowing thedistribution ofthesub-detachment nappes(indarkgrey),which arecharacterized rt i eprecn etnin ete radially either extension, experiencing that is reveals seismicity Crete Modern Crete. still in is ongoing deformation that exists evidence Abundant Active tectonicsofCrete throughout theisland(Meulenkampetal.,1994). cl to cult ssion- 2001). Fassoulas, 1999b; Postma, (Pliocene) and Veen (ten young sediments offset to documented been have faults many basins, fault-bounded continuing in the sedimentation to addition In 1992). (e.g., al., east-west et Armijo oriented or 1982) al., et (Angelier ciey pitn lnsae Fr ntne Crete instance, For landscape. uplifting actively young, a indicates also Crete of geomorphology The Figure 6-Pressure-temperature-time(P-T-t) loop Ab–albite, Arag–argonite, Cc–calcite, Jd–jadeite, of thePhyllite-QuartziteunitCrete, taken fromThomsonetal.(1998). Qz–quartz, Law–lawsonite. 21-05-2004, 14:35:33 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

Figure 7 - Time-temperature evolution of the Phyllite-Quartzite unit in central and western Crete. As noted by Thomson et al. (1999), paleogeographic constraints suggest that the Phyllite-quartzite unit entered the subduction zone 4-7 m.y. before deposition of the youngest Plattenkalk sediments. Seidel et al. (1982) and Jolivet et al. (1996) report K-Ar and Ar- Ar dates from white mica which likely record sub-closure temperature growth of mica during metamorphism at depth. Brix et al. (2002) report zircon ﬁ ssion track ages from central and western Crete, indicating cooling through about 240°C at about 18 Ma. New (U-Th)/He data (obtained in collaboration with Peter Reiners) indicate that cooling through about 180°C at about 10 Ma. Apatite ﬁ ssion-track ages (measured by Ray Donnelick) indicate cooling through 120°C also occurred at around 10 Ma. Finally, the observation of cobbles derived from the Phyllite-Quartzite in the sediments of the Fotokadhon Formation indicates that exhumation was complete by 9 Ma.

is famous for several large gorges, such as the beneath Crete, driving tectonic uplift. In addition to Ha gorge in eastern Crete and the Samaria Gorge explaining the modern uplift, underplating is also in western Crete. Messinian deposits are found consistent with seismic observations. In contrast to throughout the island, sometimes at elevations in the Aegean Sea, the crust beneath Crete is typically excess of 1000 m, indicating substantial uplift in the 35 to 40 km thick, which is odd given that the late past 5 m.y. (Meulenkamp et al., 1994). In a detailed Cenozoic normal faulting should have substantially biostratigraphic study, Meulenkamp et al. (1994) thinned the crust. Knapmeyer and Harjies (2000) demonstrated that maximum uplift in Pliocene to identify low velocity rocks beneath Crete which Recent times in central Crete was on the order of they interpret as recently underplated sediments. 2000 m. A 14C study of wavecut terraces in western Platt (1986) has argued that underplating can cause Crete demonstrated that uplift along the south coast extension within a subduction wedge. We suspect that is occurring at rates of up to 6 m/yr (Pirazzoli et al., at least some of the extensional faulting observed in

1982). Crete is related to underplating, as was also proposed n° 2 Volume - from B16 to B33 What is driving the modern uplift of Crete? Some by Fassoulas et al. (1994). workers, such as Meulenkamp et al. (1988), We note that this view contrasts with models that emphasize the role that recent reverse faults have regard Crete as a rigid, non-deforming backstop to played in Crete. In this model, Crete is thickening the sediments of the Mediterranean Ridge (e.g., Kopf and uplifting due to horizontal contraction associated et al., 2003; Le Pichon et al., 2002). Although the with the opening of the Aegean Sea. One attractive rocks of Crete have higher seismic velocities than the alternative, ﬁ rst proposed by Le Pichon and Angelier unlithiﬁ ed sediments that compose the Mediterranean (1979), is the underplating of subducted sediments Ridge, the abundant evidence for active deformation

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: n rgd aho, s eurd o te backstop the for part required as Crete view to as prefer we Thus, interpretation. fashion, rigid a in behaving not is island the that clear it make Crete on rnig xs n ae smerc ih southward with asymmetric are and axes trending east-west have generally folds The folds. mesoscale isoclinal to tight by characterized is Plattenkalk was The section the of part deposited intheEocene(Bizonetal.,1976). this that indicating present here, are fossils undeformed Sparse Mountains. this at seen Psiloritis the to Anogia be from road the along locality, can are beds characteristic These section. the of bulk the up with make that horizons interbedded chert limestones platy of succession the a of margin from continental name its gets Group The microcontinent. Adria southern sedimentary the the of represents and cover that dolomites, limestones marbles, platy of sequence through Oligocene Permian a Group, on Plattenkalk the exposed is E024.88907 Crete unit tectonostratigraphic deepest The Elevation: GPS: Folded PlattenkalkGroup Stop 1: village of Anogia alongcurveinroad. fromthe km 3.6 about at over Pull Plateau. Nida the towards Anogia from road the on southward Drive Cretan Nida Plateau. the the to up road the on of southward heading Anogia, of exposures area detachment fault. The trip will depart from the village excellent the Additionally, here. contains accessible are start units a for tectonostratigraphic important area of ideal all nearly an because is This Crete. central of Mountains Ida) (or Psiloritis the in trip Weour begin Psiloritis Mountains,CentralCrete Field itinerary this subductionwedgesystem. of side back the to corresponding Crete of side north of doubly vergent wedge (e.g., Willett, 1999), with the od.Te eomto i te ib ws apparently was limbs the in deformation The folds. the of vergence top-S the with consistent geometry a with the limbs, overturned and upright the is both on same intersection cleavage-bedding the that Note that fl by primarily developedhave indicating folds the thickness, their maintain generally Plattenkalk the of layers folded the Here, vergence. N35.26891 960 m DAY 1 exural shear.exural we will pass through the detachment and can be seen be can throughand detachmentpass the will we Continue to drive southward. As we climb in elevation, and Seidel,1991). (Theye 350°C and GPa 0.8 at estimated conditions T horizons P- maximum reached rocks these that fact the despite limestone platy the in metamorphism for evidence little is there because dry, very must been have Plattenkalk the of bulk The recrystallization. fl for pathways mark may features These contacts. bedding at and cracks around observed commonly are size grain in increase an and recrystallization However, texture. fi a have rocks Plattenkalk the Generally at theHellenicsubductionzone. attributed to thrusting during late Oligocene accretion commonly is folding this Thus, detachment. Cretan the with associated deformation extensional the with inconsistent is folding the of geometry the and Ma) younger been 29 (about Plattenkalk youngest the of havedeposition than must Folding Plattenkalk. in the recognized are greater and m 500 of amplitudes of larger fold, especially given the fact that folds with limb a in shear to due be could deformation this that Note shearing. top-S outcrop-scale an by dominated about 11.7kmfrom Stop1. after road the of side the along over Pull outcrops. which lies Tripolitza,above the detachment, is the exposed in rockier whereas subdued, more and platy is Plattenkalk west. The and east the to hillslopes the in Ma (Thomsonetal.,1999). fl this from zone) ( foraminifera describe It also provides a useful age datum: Bizon et al. (1976) zone. subduction the approached Plattenkalk platform carbonate the as material continental siliciclastic infl an represent to thought is and Plattenkalk, metafl This it islocallycalled. of package thick metafl or sandstone, turbidite metamorphosed m m-30 10 approximately interbeds an to chert with limestones platy well-bedded the from occurs facieschange a and unit, the of rocks youngest the reached have we Here, Plattenkalk. the Nida the towards Plateau, we have southward moved stratigraphically upsection in road the Following Elevation: E 024.87861 GPS: of thePlattenkalk Oligocene “metafl Stop 2: N35.22268 yc itra i te onet at f the of part youngest the is interval ysch 1433 m ysch that give that ysch 28.3 to 29.3 of age an ud ta pooe metamorphic promoted that uids ysch” atthetop lbgrn ampliapetura Globigerina n grained ne 21-05-2004, 14:35:38 ysch as ysch ux of ux EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

The fl ysch has a weak, gently dipping bedding. A structures that indicate top-S motion at this location penetrative cleavage dips towards the north, as well on the detachment fault. Brittle, low-angle shear as a spaced pressure-solution of cleavage that dips to zones dip into the detachment zone. A schistosity has the south. Minor boudinage in the carbonate layers developed parallel to the detachment, and a steep, indicate that the rocks have experience some degree northward dipping foliation is present in the fault of layer parallel extension. gouge. Continue driving southward. After about roughly 2 Return from the church to the main road. Continue km from stop 2, turn left on a small access road that southward towards the Nida Plateau. After about leads to the church of Agios Fanourios. After driving 2.3 km, pull over on the left side of the road at the a short distance you will see a driveway on the left GeoParks sign which provides a description of the side of the road which leads up to the church. Park in local geology. the area behind the church. Stop 4: Stop 3: Scenic view of the Cretan detachment and The Cretan detachment at the church Nida’s Plateau of Agios Fanourios GPS: N 35.21531 GPS: N 35.21425 E 024.85879 E 024.87474 Elevation: 1400 m Elevation: 1395 m This location provides a scenic west-facing view of In central Crete, the HP-LT metamorphosed the Cretan detachment cutting through the landscape Plattenkalk rocks are tectonically covered by (Figure 9). The tallest peaks of the Psiloritis Mountains unmetamorphosed limestones of the Tripolitza are visible to the west. Towards the southwest (left Group. These units are separated by the Cretan side of view), one can see the sharp low-angle detachment, a signifi cant Miocene normal fault, contact between the Tripolitza nappe forming the which has cut out approximately 20 km of structural mountainous peaks and the whitish, folded rocks of section. An excellent exposure of the detachment the Plattenkalk nappe below. This view is cut by a can be found behind the church of Agios Fanourious moderately dipping E-side-down normal fault which (Figure 8). The fault zone is nearly horizontal at this offsets the nappes and the detachment. Thus, the location. The footwall is the Oligocene metafl ysch of continuation of the detachment to the north (right side the Plattenkalk (same unit as the last stop), and the of view) can be found in a lower position near the base hangingwall, Tripolitza limestone. of the mountain. The relatively weak metafl ysch preserves brittle This view also provides a nice view of a large Volume n° 2 Volume - from B16 to B33

Figure 8 - Panorama of the Cretan detachment fault at the church of Agios Fanourios (Day 1, Stop 3). Here, the detachment fault is nearly horizontal. Limestones of the Tripolitza Group in the hanging wall rest upon the metamorphosed Platenkalk ﬂ ysch. Brittle shear-sense indicators developed in the ﬂ ysch indicate top-S motion along this part of the detachment.

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: including kink folds and S-C structures, are consistent structures, the Again, surface. detachment the marks that break stratigraphic the below directly zone of m 2 to detachment. 1 a in the developed well are structures of zone Fault exposure excellent another is road the of end the at taverna the of west the to Just Elevation: E 024.83489 GPS: indicators (OptionalStop) Well preserved top-Sshearsense Stop 5: 4.6 km.Park nearthetavernaatendofroad. Continue along the road towards the Nida Plateau for was raised(seebelow). the view. According to legend, this cave of is where side Zeus northern the on fault normal the of scarp the the at visible is Cave Andro Idaion the Furthermore, belowsurface.m the 950 of depth a reach tunnels the Plateau, Nida the of east cave, Tafkoura nearby the In system. cave extensive an created has weathering plateau. the of The end northern the at recognized are sinkholes Several weathering. karstic to due formed In the foreground, one can see the Nida Plateau, which Oligocene accretionofthenappes. was to attributed also what are Theytoday. 1 of stop at observed versions larger are folds These fold. south-verging asymmetric, large, a into folded is it viewthe of end towardsnorthern ridge, the the of top the of most along coherent is unit the of limb upper recumbent fold in the Plattenkalk nappe. Although the See text(Day1,Stop4)for details. Figure 9- A panoramaofthePsiloritisMountainsabove Nida’s plateauincentral Crete. rpeie t Zu’ ahr Cou, ht e would he that Cronus, father, Zeus’ to prophesized Andro cave in the Psiloritis Mountains. An oracle had Idaion the in here raised was pantheon, Greek the god in powerful most the Zeus, legend, to According Cultural note:theIdaion Andro cave with atop-Smotiononthedetachmentfault. N 35.20684 1301m yps wo ae fr h cid Amd youths Armed child. around dances war performed Kourites the as known the for cared who Nymphs, two to Zeus entrusted Rhea Zeus. son his was it that thinking it devoured who Cronus, to it presented and clothes swaddling in stone a wrapped She Crete. on cave Andro Idaion the at him hid son, secretly she youngest Zeus, her to birth gave she when and of this, tired grew Rhea, wife, His him. not harm would to able they be that so born were they as children his of each In ate Cronus children. fate, this avoid his to attempt of an one by overthrown be day one road foranother1.5km. section continuous about rock. Pull over nearly and stop after continuing up the a exposing town, of out the village of Gonies. A road on the right heads uphill reach should you km 7 about After east. the towards heading mountains. Turntown, the leave into to right up took we that path the retracingAnogia, to Return Irakleio the Archaeological museum. at displayed today silver, artifacts, stone gold, and abundant, revealed have excavations Archaeological times. Classical and Minoan during Crete in site religious important most the to been have appears Andro Idaion the myth, this of Because brought theendtoreignof Titans. that revolt a led Zeus siblings, his by Aided sisters. regurgitateZeus’to Cronus ﬁ force to able were they and Metis) story the of versions some (in Gaia by aided was Zeus matured, he After cries. the young Zeus’ cradle, to drown out the young child’s otnos eto ta epss l o te supra- the of all exposes that section continuous nearly a view to opportunity an provides road This Elevation: E 024.92609 GPS: The supra-detachmentnappesequence Stop 6: N35.28664 700m ve brothers and brothers ve 21-05-2004, 14:35:41 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

Figure 10 - Schematic cross-section illustrating the structure of the upper-plate units in the area of the village of Gonies (after Fassoulas et al., 1994).

detachment nappes. The traverse, walking downhill After the windmill is a litholigically heterogenous along the road, will move upsection through this assemblage of rocks characteristic of the Uppermost structural sequence (Figure 10). Note that the section nappe. The fi rst exposures are calcareous-siliciclastic is cut by a number of minor normal faults, which have sediments of the Vatos member. These are followed obscured original contact relations and thicknesses of by ultra-mafi c rocks and the serpentinites. Continue the nappe units. walking towards the left at the split in the road. Walking down the road, the fi rst outcrops are in Exposures of serpentizied ultramafi c rocks and limestones of the Tripolitza, which grade upward subordinate mafi c rocks continue for the next several into Eocene sandstone and minor conglomerate of hundred meters where we reach the end of the traverse the Tripolitza fl ysch. These siliciclastic sediments at the intersection with the main country road. are thought to represent continental-derived trench- You will see evidence of several normal faults within fi ll deposits, which would have accumulated as this interval. Brittle shear-sense indicators show the Tripolitza platform approached the Hellenic top-N motion on these faults. They are attributed subduction zone (e.g., Hall et al., 1984). The to widespread late Cenozoic extensional faulting Tripolitza fl ysch is much thicker than the fl ysch at the that followed Oligocene accretion of the nappes top of the Plattenkalk, and is typically on the order of (Fassoulas, 1994). 100 to 200 m. The entire thickness of the Tripolitza is Reset the odometer on your vehicle. From the downhill about 700 m thick. end of this section of road, begin to drive back towards Continuing downhill (and upsection), we pass into Anogia. A little more than 1 km out of there will be an n° 2 Volume - from B16 to B33 the Jurassic red ribbon cherts of the Pindos nappe. intersection with a sign pointing towards Aidonochori. These rocks contain radiolarites and chert with shale Turn right, towards Aidonochori. Past the village of interbeds, and are exposed for about 150 m along the Aidonochori, turn left at the fork in the road onto a road. At this point, the ribbon cherts grade into the gravel road. On your left you should see Miocene Pindos fl ysch, which here consists of about 75 m of sediments. Follow this road to the town of Chonos siliciclastic sandstone, shale, and minor ribbon chert. and take the left road out of town towards Drosia. The This unit continues to the break in exposure near the outcrops in this area belong to the Plattenkalk Group. windmill on the west side of the road. After reaching Drosia, turn left out of town, towards

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: hs od ni te dmtr ece aot 65 km 16.5 about reaches odometer the until road this up Drive Stabros. Timios of Monastery the towards right turn village,Doxarou. Withinthis of village the codn t Etn e a. 17) w ae driving are we (1972), al. et Epting to According are actuallydriving downsection. Group (Figure 11). As we drive towards the north, we to view the much of the stratigraphy of the Plattenkalk opportunity an provides section This Plattenkalk. the of section continuous long, a through pass we coast, northern the towards road the along north Travelling Elevation: E 024.88744 GPS: Stratigraphy ofthePlattenkalk Stop 8: previous stop.Pullover alongthesideofroad. the from km 9 about roughlyreached have you until the to heads that road PassAloides. of village.villageContinue through the the on left Turn town. the through straight continue and Drosia to back Drive layers the have that deformedinternally. indicate thickness layer in changes Additionally, localities. other at as sharp as not are folds the Psiloritis of higher hinges The the 1). Stop 1, in (Day experienced Mountains exposed those apparently than here temperatures rocks The the towards east. gently plunging lines, hinge trending east-west roughly have folds These unit. the Plattenkalk in folds south-vergent asymmetric, host spectacular strata These horizons. into platy back characteristic and the upsection walk we southward slope, walk the we down As stops. previous at the saw lack we strata that interbeds These chert with limestones platy Group. distinctive Plattenkalk the of parts lower the are core its In antiform. large a into folded is Plattenkalk the road, north-south this Along Elevation: E 024.84586 GPS: Ductile folds inthePlattenkalk Stop 7: and parkalongsidetheroad. o e oe Jrsi. ial, oe dw w move we down lower Finally, Jurassic. lower be to thought massive,marbles encounter white we section down move we As deposits. chert with interbedded Plattenkalk the limestones, platy characteristic the in of Webegin unit. stratigraphy entire the through south-vergent recumbent fold. This allows us to move asymmetric, large, a of limb overturned the through N35.35980 N 35.37925 400m 370m n lentv hs en rpsd y al and Hall of structure the fold, recumbent single a of consisting than by rather that argue proposed who (1983), been Audley-Charles has alternative An to beabout2600m. (1972) estimate the entire thickness of the Plattenkalk al. et Epting dolomite. stromatolitic Triassic the into Figure 11-StratigraphiccolumnofthePlattenkalk Group incentralCrete,simpliﬁ and Audley-Charles (1983). ed fromHall 21-05-2004, 14:35:45 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

the Plattenkalk in this unit is dominated by many tight straight part of the road, immediately pull over on the isoclinal folds that repeat many parts of the section. right side of the road. Fossils of the “Fodele beds” They also infer the existence of several faults that can be seen in the outcrop along the side of the road. repeat parts of the section. They infer a maximum thickness for the Plattenkalk Group of about 1000 m. Stop 9: The Plattenkalk Group sediments record the The “Fodele beds” of the Plattenkalk deepening of a sedimentary basin. The oldest part GPS: N 35.38406 of the section is composed of shales and massive E 024.91861 stromatolitic dolomite, indicating intertidal Elevation: 115 m sedimentation. Upsection, these rocks give way Fossils of the “Fodele beds” of the Plattenkalk Group to carbonate breccias and channelled and graded can be seen in the outcrop along the side of the road. calcarenites. These are interpreted as recording rapid These represent the oldest part of the Plattenkalk subsidence of the platform following the Triassic Group (Epting et al., 1972). Visible with the naked (Hall and Audley-Charles, 1983). Farther upsection, eye are abundant corals, bryozoa, and brachiopods the calcarenites grade into fi ner grained more (Kuss, 1980). Although these rocks experienced high- basinal deposits of the characteristic limestone-chert pressure metamorphic conditions, the fossils show sequence. Similar deposition is inferred to continue no evidence for deformation or recrystallization. more or less continuously through the Mesozoic and In-fi lling structures in both corals and gastropods early Cenozoic until the addition of the siliciclastic indicate the beds here are overturned. material of the Oligocene metafl ysch at the top of the Turn the car around and head westward. The rest of section. the stops take place in western Crete, and you will At the fi eld guide stop, we will see the beautiful want to drive as far westward as possible before the Triassic stromatolites. Here, these structures clearly next day. Both Rethymno and Chania are nice cities to show that the sedimentary section is overturned. visit for an evening. Continue down the road. As we near a bend in the road at about 1 km from the last stop, pull over. DAY 2 The metabauxite horizon is not obvious and can be Phyllite-Quartzite Nappe In Western Crete diffi cult to fi nd in the outcrop. The GPS coordinates provide the best means of fi nding the location of the Day two is focused on the Phyllite-Quartzite nappe, metabauxite. the structurally highest of the sub-detachment nappes. This unit has been intensely studied, including its Stop 8 bis: metamorphic, thermochronologic, and deformational Metabauxite horizon within the history. We will examine the Phyllite-Quartzite Group, Plattenkalk (Optional stop) discuss both the ductile and brittle deformation in the Elevation: 277 m unit, and consider the processes responsible for its N 35.38589 exhumation. E 024.89451 Drive westward along the National Road. As you drive Continuing down the road, we encounter rocks westward past Chania, you will note many exposures from deeper in the stratigraphic section. At the of Miocene sediments in large roadcuts. Most of these base of the stromatolitic dolomite is a metabauxite sediments were deposited in the Pliocene. We will horizon, signifi cant because it provides the only discuss the signifi cance of the Miocene sediments in thermobarometric data from within the Plattenkalk greater detail tomorrow unit (Seidel et al., 1982; Theye et al., 1992; Theye Eventually, you will pass over onto the western side and Seidel, 2001). The assemblage within the of the Rodopos penninsula and to the north the Bay n° 2 Volume - from B16 to B33 metabauxite contains magnesio-carpholite coexisting of Kissamos will be visible to the north. Look for the with pyrophyllite, sudoite, and disapore, leading to an road that leads to Nopigia. Turn right, and follow estimate of metamorphic conditions at 0.8 GPa and the road to the coast. When it approaches the coast, 350°C. this road turns towards the east. Follow it along the Continue all the way down until you reach the National western side of the penninsula. The paved road will Road. Turn right (towards the east) and drive for 4 give way to gravel, and farther along there will be km. The road will have a large hairpin turn. When a white church. Drive past the church and over the you are through this turn and begin travelling on the small crest in the road. Park in the pulloff adjacent to

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: become increasingly common in the younger part of part younger the in common increasingly become beds Carbonate present. also are intrusives basic and metavolcanics,carbonates, some although sediments, The older parts 1983). of the section are al., dominated by siliciclastic et (Krahl Triassic to Carboniferous from ranging ages conodont numerous unit yielded The has setting. marine a in deposited was Group Phyllite-Quartzite the that indicate fossils Conodont layers arealsolocallypresent. a Severalcarbonate-rich thick. from m 1 about to up fewcm ranging beds with phyllites, and quartzites bedded well of consists section The Group. Quartzite Nopigia of provide a representative view of the Phyllite- village the near exposures coastal excellent The Elevation: E 023.72288 GPS: The Phyllite-Quartzite unit Stop 1: National Road. outcropfromkm 2.4 about is intersectionthe the with This coast. the along be will outcropsrocky several (X-Y section).Notetherethatthefi direction byprecipitationoffi undulose extinction.However, thegrainshave beenshortenedintheZdirectionbydissolutionandextendedX the horizontal.Theindividualquartzgrainsshow littleevidencefor internaldeformation, such asrecrystallizationor respectively. a) A quartzitethinsectionillustratingthepressure-solutionfabric,withZorientedinvertical, andXin Y andZindicatetheprincipalstraindirectionsfor maximumextension,intermediate,andshortening, Figure 12-PhotomicrographsillustratingtheductilemicrostructurescommoninPhyllite-Quartzitenappe.X, r gnrly o a peaet s n h Plattenkalk. the in as prevalent as not folds generally are such but folds Phyllite-Quartzite, were the mesoscale in see elsewhere folds will We here. that bedding developed not indicating consistent throughout shows attitudes section Nopigia The 2, Stop7). fi the in later see will we as section, the N35.51943 3m brous overgrowths. b)Thesamesampleasin(a)but hereobserved paralleltocleavage brous overgrowths areorientedinalldirectionsindicatingafl eld trip (Day trip eld irsrcua ivsiain so ta these that processes solution pressure by show deformed have rocks investigations Microstructural symmetric, but there seems to be a predominance of predominance fairly a be to are seems there but symmetric, structures zone Fault faulting. distributed brittle strongly by been have which phyllite and quartzite thinly-bedded of composed is outcrop The shoreline. the of east the to hillslope at the of outcrops base the the in seen be can zone shear brittle A shearing to attributed is during thepressure-solutiondeformation. outcrop the in present at that seen views the of orientation oblique The diagenesis. argue during bedding (1996) to perpendicular formed Stöckhert veins these and Schwarz beds. particularly abundant in the more competent quartzite are and locality this in common veinsare quartz Thin the cleavage (Figure13). to parallel directions all in occurs which extension, signifi is cleavage the to indicated by the fact that the shortening perpendicular fl Our mass-loss (anisochoric) a cleavage. indicate “beard-shaped” measurements to strain absolute and parallel cleavage oriented the overgrowths by truncated grains quartz see to possible is plane. it lens, foliation hand a With the within direction extension the fi as redeposited and direction shortening the to perpendicular grains quartz detrital of surfaces from removed material with 1999), al., et Stöckhert 1996; Stöckhert, and Schwarz 12; (Figure atnn dfrain Ms-os is Mass-loss deformation. attening cantly greater than the total the than greater cantly bos vrrwh in overgrowths brous attening deformation. 21-05-2004, 14:35:49 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

Figure 13 - Nadai plot showing absolute strain data from the Phyllite-Quartzite Unit in western Crete. All samples except one show a ﬂ attening strain. Uniaxial shortening was compensated by extension in all directions within the foliation plane.

top-S kinematic indicators. Farther north along the coast, we can see Miocene carbonates capping the ridge. Farther up, a roughly N-S trending fault drops down rocks to the west. We can see the Miocene sediments near sea level, illustrating the signiﬁ cant offset along this fault. We will return to these north-south trending faults when we discuss the neotectonics of the island.

The Phyllite-Quartzite rocks are useful for studying the metamorphic, deformation, and exhumation history of the HP-LT rocks in the footwall (Seidel et al., 1982; Jolivet et al., 1996). of the Cretan detachment. Unlike the Plattenkalk Return to the National Road and travel westward Group, which is dominated by carbonates, the siliciclastic lithologies of the Phyllite-Quartzite towards Kissamos. Continue through to the town of contain assemblages amenable to metamorphic and Platanos. Follow the western coast road towards the thermochronologic study. The peak metamorphic village Sﬁ nari. Pull over in a turn off approximately conditions for the Phyllite-Quartzite throughout Crete 20.4 km from the intersection of the National Road are loosely bracketed to between 0.4-1.0 GPa, and and the road to Nopigia. 300-400°C by the co-existence of pyrophyllite, low albite, and lawsonite, plus local aragonite and jadeite Stop 2: (Seidel et al., 1982; Theye and Seidel, 1991; Theye et Brittle deformation and extension al., 1992; Brix et al., 2002). Thermobarometry using GPS: N 35.44627 phengite-muscovite solid solution and exchange E 023.57976 between carpholite and chloritoid suggests that Elevation: 228 m metamorphic grade increases systematically from Park at the pulloff just past one of the tight turns at eastern to western Crete, from 0.6 GPa and 300°C in the north end of the West Coast road. Numerous fresh the east to 1.0 GPa and 400°C in west. However, we cuts along this road provide an excellent view of both

note that these estimates assume an H2O activity of brittle and ductile structures in the Phyllite-Quartzite unity. If the activity of water deviated from one, the nappe. The pressure solution fabric is similar to that maximum temperatures experienced by the Phyllite- observed at the Nopigia locality (Day 2, Stop 1). n° 2 Volume - from B16 to B33 Quartzite could be much less. The preservation of Anisochoric fl attening strains have been measured aragonite also suggests lower peak temperatures, since here as well. Quartz C-axis measurements show aragonite would have quickly inverted to calcite if the no development of a lattice preferred orientation, rocks entered the calcite stability fi eld at temperatures once again indicating that pressure solution was the signifi cantly greater than about 235°C (Liu and Yund, dominant ductile mechanism (Schwarz and Stöckhert, 1993). K/Ar and Ar/Ar dates from syn-metamorphic 1996). Mesoscale isoclinal folds are locally present at white micas in the Phyllite-Quartzite suggest that several locations along this traverse. metamorphism occurred between 21 and 24 Ma Throughout Crete, the Phyllite-Quartzite nappe is

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: cleavage and likely post-dates the pressure-solution higher temperatures the overprints This deformation nappe. brittle Phyllite-Quartzite the within coaxial extension N-S involve to appears deformation brittle regional15). the (Figure the at indicators scale, Thus, top-S and top-N of distribution equal nearly a with offset, normal-sense show faults measured the almost of all Crete, western In nappe. Phyllite-Quartzite the in strain brittle the assess to indicators these used with R shears and P foliations most common. We have structures, composite indicators Reidel as usually abundant, are kinematic Brittle thick. several m several are to that cm zones gouge have These typically Phyllite-Quartzite. faults the pressure in dipping cleavage gently solution more the to high-angle a at lie generally the zones fault along These road. displayed Coast West well is (Figure relationship faults This brittle 14). numerous by cut commonly zone inwestern Crete(Day2,Stop2). Figure 14-Photoofawell-developed normal-sensefault the Phyllite-Quartzite unit from an unmetamorphosed everywhere is overlain by Phyllite-Quartzite a the low-angle fault road, that separates of stretch this Along of theCretandetachment. developmentCenozoic late with synchronous be may faulting brittle Thus, metamorphism. with associated idea. this develop fully more to then until wait will we so convincing, more is Topolia at evidence The 2003). in the hangingwall of Cretan detachment (e.g., Seidel, deposited were that basins syn-extensional represent units conglomeratic these that is idea emerging An 2). Stop Topolia(the 3, trip Day the conglomerate, in later conglomerate Miocene(?) similar a see Wewill Phyllite-Quartzite the zone, clasts disappear, and fault only limestone clasts are present. the in up Farther material. Phyllite-Quartzite of clasts angular contains that breccia a is zone fault the of part lowermost the in Here, klippen. the beneath a zone fault allowing the of road, view main the from down goes trail A Group. look as if they may have been derived from Tripolitza which cobbles, limestone rounded of mainly consists and supported matrix is there conglomerate The unit. Miocene(?) this of klippen a is road the in the turn next near down ridge next the At structure). this for 12 in Jolivet et al., 1996 shows a similar interpretation (fi detachment Cretan the of part high-level a as fault low-angle this interpret We carbonate 16). (Figure clasts of composed conglomerate Miocene(?) s . k, rud tr js ps te ilg of village the past just turn Kampos. a around km, 9.8 is stop Sfi next Sfi From of the village nari. nari, the to Continue following the western coast road southward observed here may be a local feature. The curve in the geometry fold the and Plattenkalk, the in are they nappe as Phyllite-Quartzite the in common as not are however,folds experience, our In nappes. Cretan the to deformation associated with Oligocene accretion of attributed also are these Plattenkalk, the in folds more the and thinned, commonly Like boudinaged. are horizons quartz-rich competent are folds these of limbs The E-W. approximately trend that axes have folds of set second The lineation. stretching NNE a and cleavage horizontal nearly a with associated are isoclinal recumbent of folds, with fold axes trending NNE-SSW. These folds consists set older The 17). both of which can be observed at this location (Figure Crete, western in folds of sets two recognized have (1999) al., al. et Stöckhert 1999). et al., et Thomson 1999; Stöckhert 1982; (Greiling, Phyllite- nappe the in Quartzite found locally are folds Mesoscale Elevation: E 023.56462 GPS: Folds inthePhyllite-quartzite nappe Stop 3: N35.38727 313m 21-05-2004, 14:35:53 gure EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

Figure 15 - Lower hemisphere stereonets showing slip-linear data for brittle fault zones within the Phyllite-Quartzite nappe in various areas in western and central Crete. Each square represents the pole to an individual fault plane. The arrow represents the direction of motion of the footwall block relative to a ﬁ xed hanging wall block. (Arrows pointing away from the center of stereonet indicate normal-sense slip.) Fault planes show a variety of orientations and nearly all record normal-sense slip. Volume n° 2 Volume - from B16 to B33 road here provides a good opportunity to look at these access road. folds in different orientations. Continue driving southward. Approximately 7.6 km Stop 4: from Stop 3, the road will bend back towards the Triassic evaporites in the Phyllite-Quartzite nappe interior of the island, with a turnoff on the south side (Optional stop) of the road. Park your vehicle in the turnoff, and GPS: N 35.35306 walk along the access road that leads downhill. The E 023.56938 evaporites for stop 4 are exposed along the side of this Elevation: 510 m

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: rasc vprts r peet oal i the in are evaporites locally recrystallized and deformed in a manner similar to the the Here, present nappe. Phyllite-Quartzite are evaporites Triassic od oad te ih ta las o h vlae of village this the Past Strovles. to the leads that Take right the Chania. towards road towards drive and and Chania Elaphonisi, connects that road the Join Kefali. of village throughthe road,passing the along Continue youngest the with Tripolitza beinglate Triassic. units, stratigraphic two known Phyllite-Quartzite being Triassic in age and the oldest these no is in there overlap that note They nappes. supra-detachment the of one is which Group, Tripolitza the by depositionally overlain originally 1983) Audley-Charles, have speculated that the Phyllite-Quartzite Group and was Hall 1984; (Bonneau, workers Several subducted. deeply be to and cover overlying its Triassic from detach to nappe Phyllite-Quartzite the that the allowed suggest that horizon weak a as servedevaporites (1999) al. et Thomson more to upwards carbonaceous andevaporitic units. grade age, in Permian mainly is which section, the of part lower the characterize that quartzites and phyllites the 6), Stop 2, (Day stop later a at see will we As Group. Phyllite-Quartzite the of These Triassic evaporites are near the stratigraphic top attributed torift-related breakupofPangea. are and Europe in common are age this Evaporitesof (Fassoulas,2000). rocks Phyllite-Quartzite the of rest and Phyllite-Quartzitenappeinthefootwall (Day2,Stop2). Figure 16–Photolookingnorthward, showing theCretandetachment faultwithMiocenesedimentsinthehangingwall village, take the right fork in the turn approximately 3.1kmsouthof Voutas. hairpin the in Palaiochora.towardsroadoff the Pull Pal towards south continue Voutas, reach you After Voutas. and Arhondiko of village the towards road nt s ossety smerc wt a dominant a with asymmetric, consistently is unit argue Phyllite-Quartzite the in deformation extensional that (1996) al. et Jolivet fault. detachment major the which along motion the regards question important breccia An tectonic Note contains angularclastsofthe Tripolitza. nappe. Tripolitza supra-detachment the of exposures several are road this Down downhill. runs road access small a turn, On the western side of the road, just prior to the sharp consistent withtop-Smotion. indicators towards sense shear several contains dips and south the zone fault wide m 20 approximately The detachment. Cretan the of exposure excellent an Voutasis of south road the in turn hairpin the Near Elevation: E 023.66350 GPS: The detachmentfaultnear Voutas Stop 5: ugss ht eomto wti te Phyllite- the on least the at coaxial, generally within is unit deformation Quartzite that evidence suggests microstructural our before, discussed As Crete. central in deformation symmetrical a arguefor (1994) al. et Fassoulas shear,whereas of sense top-N N 35.27345 277m 21-05-2004, 14:35:58 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

micro-scale. Although Jolivet et al. (1996) admit Stop 6: that the deformation is “partly coaxial” on a small Deformed marbles within the Phyllite-Quartzite scale, they maintain that mesoscale observations are nappe consistently top-N. However, the detachment here GPS: N 35.29030 south of Voutas is clearly top-S. Recall that, when E 023.61844 visible in the Psiloritis Mountains, the detachment is Elevation: 607 m also top-S. Between the villages of Sklavapoula and Agioi We agree with Jolivet et al. (1996) that there are many Theodoroi is a long roadcut that exposes Triassic localities in which deformation appears to have a top- carbonates of the Phyllite-Quartzite Group. These N shear sense. However, we do not believe that the beds, known as the Kalamos formation, alternate deformation is systematically asymmetric. Therefore, between marbles and metapelites (Theye and we favor a model for the exhumation of the lower Seidel, 1993). The petrology of these rocks has been plate rocks along two separate detachment faults, one described in detail by Theye and Seidel (1993). They dipping northwards and the other dipping towards the report that limestones are lawsonite-bearing aragonite south. marbles, which in many cases have been partly or Return to Voutas, and take the road westward out of completely inverted to calcite marbles. The presence town towards Sklavopoula. The road to Sklavapoula of unretrograded aragonite provides an important is very windy and hilly. Upon reaching Sklavapoula, constraint on the P-T history of these rocks. Work turn left towards Agioi Theodoroi. by Carlson and Rosenfeld (1981) and Liu and Yund Volume n° 2 Volume - from B16 to B33

Figure 17 – Synoptic diagram illustrating deformation structures within the siliciclastic rocks of the Phyllite-Quartzite nappe of western Crete, from Stöckhert et al. (1999). B1, S1, str1 denote ﬁ rst-generation fold axis, schistosity, and stretching lineation. B2, S2 denote second generation fold axis and schistosity (crenulation cleavage in phyllites). Ph: phyllites; q: quartzites; v1: veins formed along original joints normal to bedding in sandstone; during deformation these veins were rotated and stretched, with boudinage of the original carbonate ﬁ lling (black); quartz (white) was precipitated between the boudins; v2: veins formed during HP-LT metamorphism along S1 in phyllites, folded (B2) during progressive deformation and recrystallized; v3: later formed veins crosscutting all earlier structures, undeformed and with original microstructure preserved. Insets A to E reveal characteristic microstructures and their respective positions.

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: ihsrtgahc nt ta se t wr wl in well work to seem defi that has units (1979) lithostratigraphic al. et Meulenkamp Crete. these western in for particularly complex, remains nomenclature sequences stratigraphic sedimentary local The many basins. of development the activity was this with Coincident started Ma. 10 to 15 exhumation about at and deformation Extensional of record exhumation. sedimentary the examine will we nappes. Today supra-detachment and sub-detachment the on focusing Crete, of history older the emphasized o te eiet o wsen rt, dpe from adapted Crete, Meulenkamp etal.(1979). western of sediments the section for stratigraphic composite a shows discussion 18 appropriate. our Figure where names in local noting (1979) while al. here, et Meulenkamp of terminology and divisions the use will we such, As representing syn-extensional basins throughout Crete. about 235°C for aragonite to survive transport to the to transport survive to aragonite for 235°C about must enter the calcite stability rocks fi aragonite-bearing that indicates (1993) n h fi the In Basin Development In Western Crete evening. the for Palaiochora to road the following Continue pressure is solution. mechanism Phyllite-Quartzite, deformation the dominant in the rocks carbonate the for even that demonstrating undistorted, completely that are layers these from fossils describe (1999) al. et Stöckhert deformation. characteristic during a structure bone” to “dog lead which layer, aragonite the than competent more are veins The buckled. slightly are which of some bedding, to perpendicular nearly fi commonly veins contain layers Aragonite structures. creating boudinage bedding, have to folds perpendicular the shortened of been limbs near- long recumbent The asymmetric folds. al. isoclinal km-scale et to into m deformed Stöckhert 100 is by sequence carbonate described The (1999). is outcrop This Michigan. Universitythe of of Essene Eric Matthewand Manon by present at study.studied being is discrepancy This than the 350°C estimates from their thermobarometry temperatures lower much imply would aragonite of preservation that acknowledged have (1993) Seidel km/m.y.).and (~10 Theye rates exhumation fast very assumes limit upper This regression. without surface rt w dy o te fi the of days two rst le wt clie n qat oriented quartz and calcite with lled DAY 3 eld at temperatures less than ed rp w have we trip, eld nd six ned hand-side oftheroad. left the on lot small in over coast Pull km. 2 about roadfor the along Palaiochora from westward Drive bevd et f aaohr a Kudua beach. Koundoura at Palaiochora of west observed be can Crete of coast southwest the of uplift Recent Elevation: E 023.66877 GPS: coast atKoundoura beach Wave-cut terracesalongthesouthern Stop 1: N 35.23722 2m Figure 18-Compositestratigraphiccolumn adapted fromMeulenkampetal.(1979). for thesediments ofwestern Crete, 21-05-2004, 14:36:05 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

You can see there a fl ight of uplifted wave-cut terraces Stop 2: exposed north of the road. Wave-cut terraces are The onset of Miocene sedimentation commonly formed as a result of sea level fl uctuations GPS: N 35.41018 (eustasy) and/or elastic deformation related to the E 023.68315 earthquake cycle. The terrace is cut when the rate of Elevation: 301 m uplift of the land matches the rate of rise in sea level. Here, we can see the oldest Neogene sediments in In this case, the surf zone can work for some time to western Crete exposed in the cliffs of the Topolia cut the platform. Preservation of the terrace requires gorge. The Miocene(?) Topolia conglomerate is that the platform be rapidly uplifted above surf zone. a poorly sorted, matrix supported conglomerate This typically occurs due to coseismic uplift, but a containing subangular to rounded clasts ranging in rapid fall in eustatic sea level could produce the same size from granules to cobbles. A variety of clasts- result. types are present, including grey to black limestones, The terraces north of the road locally show a recessed dolomites, recrystallized limestones, radiolarites, notch that marks the transition from wave-cut platform calcarenites, and micritic limestone (Seidel, 2003). to the seacliff that use to back the platform. Cemented The conglomerate has been interpreted as an alluvial sand and gravel are locally preserved on the wave-cut fan deposit, with debris fl ow and waterlaid deposits surface, and represent remnants of beach deposits. derived from a catchment to the south (Seidel, 2003). The older terraces would be located higher on the The unit is estimated to be about 500 m thick. The hillslope. These terraces have been eroded away, but coarsest deposits are located in the southern part of the at this location they can sometimes be detected by the basin, near its base. Higher up-section, the sediments presence of caves that hosted fresh water streams that are predominantly debris-fl ows in the proximal and drained to sea level. medial parts of the complex, accounting for 70 to 80% The youngest uplifted terrace is located on the beach to the south of the road. Look for a low rocky pavement of beach rock exposed just above the modern shoreline. This pavement is composed of cemented conglomerate and sand, and contains cobbles derived from the adjacent Cretan nappes (e.g., Phyllite-Quartzite and Tripolitza). A broad wave-cut platform has been cut into the upper part of this beach rock unit. Pirazzoli et al. (1982) have dated similar wave-cut terraces in western Crete the using 14C method, and they have demonstrated that uplift is occurring at rates of up to 6 m/yr for over the past 2000 years. We will focus on the modern, continuing uplift in Crete tomorrow. Return to Palaiochora and follow the main road north out of town. At the village of Plemeniana, turn left on the road towards Dris and Strovles. Continue northward through Strovles. Turn right (towards Chania) when the road reaches an intersection. Drive north for roughly 4.5 km. The valley narrows n° 2 Volume - from B16 to B33 to the north. Stop just after the memorial on the east side of the road at the bend. Walk south towards the tectonic contact between the Phyllite-Quartzite and the overlying breccia. Exercise extreme caution at Figure 19 - Photo of the Topolia breccia in western Crete. this locality. The outcrops are exposed along a windy The Topolia belongs to the Prina Group, which are the road, so be careful of traffi c. oldest Miocene sediments in Crete. Clasts within the Topolia appear to be exclusively derived from the supra-detachment nappes.

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Volume n° 2 - from B16 to B33 B32 - B32 B32 and theoverlying sedimentsoftheTefeli group. sediments inwestern Crete. An angularunconformity existsbetween theTopolia breccia Figure 20–Panorama lookingeastward fromthe village of Voulgaro, showing thelower Miocenesupra-detachment Leaders: J.M. Rahl J.M. Leaders: within this basal unit. The limestones, dolomites, and dolomites, limestones, unit. The basal this within Importantly, there are no clasts of the lower plate units of thealluvialfan. and 10 Ma (Seidel, 2003). The steep dip of the unit the of dip steep The 2003). (Seidel, Ma 10 and 20 between sometime deposited was conglomerate Topolia the that suggesting Ma, 15 and 20 between begun have to envisaged is fault detachment Cretan the on Exhumation fault. detachment Cretan the with the alluvial fan may be related to extension associated of Deposition Keupp,1996). and (Frydas Ma 9 about Sediments stratigraphically above the Topolia sediments. have been dated as the of dating direct prevents itself complex the within fossils of lack a clear, because not is conglomerates Topolia the of age The Quartzite bedrock. Phyllite- the with were contact directed conglomerates into exposed faulted the later However, not surface. were the unit at Phyllite-Quartzite rocks the plate lowerof of the deposition conglomerates, Topolia during the that suggests This from unit. derived been this have may that not cobbles does contain conglomerate Topolia the unit, However, Quartzite unit. Phyllite- the Pindos with proximity close current its the despite from derivation consistent are with limestone micritic and calcarenites, radiolarites, including cobbles, of Tripolitza types Other the unit. in found those clasts with the correspond of that some within fossils describes (2003) Seidel fact, In 19). (Figure nappe Tripolitzathe from derivedhavebeen to appear limestones recrystallized Conglomerate and theoverlying Miocenesediments. vill next the of end northern the near widens Stop gorge. the valley exit we as the northward, road the Following the depositionofthesesediments. here implies signifi age, V age, cant rotation caused by uplift since oulgaro, for a view of the Topolia the of view a for oulgaro, age (NN10 – (NN10 age Tortonian a contains of indicative which nannoplankton Formation,calcareous Potamida the of clays interfi is Roka) the authors as some by to referred (also Fotokadhon The shallowenvironment.watera in deposition marine of phases initial the record and Formation the Fotokadhon to belong Group Tefeli the of sediments oldest The 1996). Keupp, and (Frydas Group Tefeli the of sediments horizontal the are conglomerates Topolia of view basin-fi nice Miocene the a have we east, the towards Looking View ofearlyMiocenesedimentation Stop 3: Continue driving north until you reach the National the reach you until north driving Continue marker horizonthroughoutnorthwesternCrete. useful a as serve thus and distinctive are Chairetiana Formation.the Chairetiana of marls consolidated The the within contained found commonly are deposits Gypsum 1996). Keupp, and (Frydas age Messinian eiet o te icn Tfl Gop (Figure Group Tefeli Miocene the of sediments overlying the Topoliaand the between unconformity angular the an of presence of the by indicated deposition as Topolia, followed hiatus sedimentary A depositional ageofabout9Ma. that in western Crete, the Fotokadhon formation has a at eog srtgahcly o h sboe NN subzone ( the 11b to stratigraphically belongs part nannoplankton upper its while Tortonian), calcareous (latest 11a NN subzone to Vrysses the corresponds of Chairetiana group Formation. the of Chairetiana part lower the The of and clays marls sandy interbedded well-bedded, the and are formations laterally both these Above formation. Potamida the grades into upsection Fotokadhon The 20). muoihs delicatus Amaurolithus Discoaster calcaris Discoaster ll sediments in Crete. Above the AboveCrete. in sediments ll nee ad vran y the by overlain and ngered , niaig n early an indicating ), ). This demonstrates ). This 21-05-2004, 14:36:09 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

road at the eastern side of the town of Kissamos. at about 9 Ma (Frydas and Keupp, 1996). Turn right and drive towards the east. Pass the road Walk eastward on the road. Bedding in the Miocene that heads off towards Nopigia (Day 2, Stop 1) and sediments is initially steep but becomes more continue eastward for several km up onto the Rodopos gentle away from the contact. Continuing eastward Peninsula. About 10.5 km from Kissamos you will see for several hundred meters, there is a break in the a low concrete building on the right hand side of the section across the bridge. After this, the section is still road with “NISSAN” written on it. Turn into the large conglomerates, but they fi ne upward into buff-colored pullout near this building. There is a large outcrop of thinly bedded marls of the Potamida Formation. Note Phyllite-Quartzite rocks on the left-hand side of the on the southern side of the road, we can see that these road. Carefully cross the road and walk towards the sediments are capped by the marls of the Tortonian- east for about 100 m. Messinian Chairetiana Formation. The presence of cobbles of the Phyllite-Quartzite unit Stop 4: in the sediments can be used to constrain the thermal Depositional contact on the evolution of the high-pressure, low-temperature rocks Phyllite-Quartzite unit of Crete. Here, we summarize the results that we GPS: N 35.5314 have discussed thus far throughout the trip (Figure E 023.765 7). This discussion is a modifi cation of the results Here, sediments equivalent to the Fotokadhon of Thomson et al. (1999). The Oligocene fl ysch at clearly lie in depositional contact with the Phyllite- the top of the Plattenkalk unit shows that it was still Quartzite unit. The contact between the bedrock of at the surface at ~29 Ma. However, the sediments the Phyllite-Quartzite and the Miocene sediments of the Phyllite-Quartzite are though to have been is not a fl at surface, but rather has an undulating, deposited to the north of the Plattenkalk platform, hummocky nature indicating that it was at the surface meaning that the rocks of the Phyllite-Quartzite at the time. Furthermore, soil horizons also illustrate were deeply subducted prior to 29 Ma. Estimates of the depositional nature of the contact between the the rate of plate convergence during the Oligocene Phyllite-Quartzite and overlying conglomerate. and the inferred paleogeography suggest subduction Walking eastward along the road, we can see that this of the Phyllite-Quartzite sometime between 36 to conglomerate is clearly overlain by the Fotokadhon 32 Ma. White mica Ar-Ar ages, interpreted here Formation sediments and the Chairetiana Formation. as sub-closure crystallization ages, suggest peak This clearly illustrates that the Phyllite-Quartzite was metamorphic conditions were reached between 24 exposed at the surface prior to the NN10 Nannozone and 20 Ma (Jolivet et al., 1996). Previously published Volume n° 2 Volume - from B16 to B33

Figure 21 - Photo of depositional contact between the Miocene sediments of the Fotokadhon Formation and Phyllite- Quartzite unit. The Fotodakhon is about 9 Ma based on calcareous nannoplankton, providing a minimum exposure age for the Phyllite-Quartzite nappe in western Crete.

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: ok coe blw 1° aon 1 M. Finally, Ma. 10 around 210°C below cooled rocks NewMa. 18 showages He zircon lowerthe that plate zircon He ages reveal cooling through 240°C at about hs oaiy lo rvds n xeln ve o the of view excellent an provides also locality This at leastthatmuchupliftsinceabout5Ma. requiring thus elevation, m 100 at exposed are rocks These event. Messinian the with associated gypsum exposes pavement the road, the from meters few A west. the towards in leads trail small point a turn, the hairpin the E023.67421 At road. the of side the along outcrop Formation Chairetiana the of marls laminated Here, GPS: more recent faulting evaporite, Messinian Formation, Chairetiana The Stop 5: park atthehairpinturninroad. road.main the offfollowing and Pull km, 0.9 another Drive Sirikari. towards road the on right turn then and km 0.4 for Drive Kissamos). reachingbefore km left towardsRoad 1 National (about Old Chania the onto Turn Kissamos. towards back westward Drive surface by9Ma. the at bedrock Phyllite-Quartzite of exposure led the ultimately to that exhumation of pulse rapid a by followed Ma, 10 and 20 between exhumation modest with history, exhumation -phase two a experienced were Cretan the of footwall the in rocks HP-LT the rocks at the surface at about 8.5 Ma. This HP suggests that the of exposure indicate deposits conglomeratic (1980) andFassoulas (2000). TheSamariaGorgebeginsintheXiloskalonareaandendsat Agios Roumeli. Figure 22-CrosssectionoftheLefkaOriMountainsin theOmalosareaofwestern Crete,modiﬁ N 35.48585 to theoutcrop. m) (50 road access the along distance short road.a Walk the of side right-hand the on off the turn at hairpin part and km 0.5 for Drive Greek). in only is sign Marediana(the roadto the up Turnkm. on right 0.6 another for road main the along north Continue relative totherocksoflongpeninsulas. down Bay Kissamos beneath rocks the dropped have These are bounded by N-S trending normal faults that peninsulas. north-south long oriented by north-south bounded waterway a Bay, Kissamos see can we north, the to Looking N-S. oriented often are these active still and recent Crete, faults. western normal In eokn. hy r fud s nebd i ﬁ in interbeds as found depositional are by They reworking. fragmented been have to appears be can crystals gypsum found E023.67142 in the low outcrops of alongside road. The gypsum clasts cm) (~20 Large Elevation: N35.48310 GPS: (Optional stop) evaporiteChairetianaMessinian formationwithin Stop 6: Chania fortheevening. to eastward drive and Road National the to Return depositional marine environment. a indicating marls, laminated 105m ed fromFytrolakis 21-05-2004, 14:36:15 nely EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

DAY 4 rocks drop down to the valley fl oor about 2 km above Samaria Gorge the abandoned village of Samaria. For the remainder of the gorge, the platy member is well exposed, We will conclude our fi eld excursion with a hike revealing numerous south vergent asymmetric folds, down the beautiful Samaria Gorge. This 16 km gorge similar to the Plattenkalk folds we saw earlier in the is considered the longest in Europe. We will take a trip (Day 1, Stop 7). bus from Chania to the Omalos Plateau and to the The boat trip from Agia Roumeli at the mouth of the entrance to the Samaria Gorge Park. The hike through gorge to Chora Sfakion provides several views of the gorge typically takes 4 to 6 hours and ends at the other south-fl owing gorges that have been cut into the village of Agia Roumeli. From there, we take a ferry southwest fl ank of Crete. This south slope also has eastward to Chora Sfakion where buses will take several uplifted wave-cut terraces (Figure 23), similar people back to Chania. to the uplifted terraces that we saw east of Palaiochora The road to the park passes fi rst through the Phyllite- (Day 3, Stop 1). Many of these terraces have been Quartzite nappe and then into the Trypali nappe after dated by Pirazzoli et al. (1982), who describe terraces the village of Lakoi. The Samaria Gorge itself is cut into of 8 distinct ages. Throughout western Crete, these are the Plattenkalk nappe. The whitish peaks at the head typically uplifted from 3 to 8 m over the past 2000 of the gorge are the Gigilos beds, the massive white to 4000 years. If sustained, these values would be marbles in the Plattenkalk that are stratigraphically equivalent to uplift rate of 0.8 to 4 km/m.y.

Figure 23 - Photograph of uplifted Holocene terraces along the western coast of Crete.

above the Triassic stromatolitic dolomite but below the typical “platy limestone” horizons (Figure 11). The southwest coast of Crete appears to coincide with The structure of the Lefka Ori region is depicted in a south-dipping normal fault, with the hangingwall Figure 22, which shows that as we hike down towards offshore to the south. Thus, the southwest coast of the coast we will travel progressively upsection in the Crete represents the footwall of this fault. The uplifted

Plattenkalk stratigraphy. coastal terraces and the deeply incised gorges along n° 2 Volume - from B16 to B33 The hike begins at an elevation of 1250 m. The the southwest coast indicate that slip on this normal surrounding peaks are typically at about 2000 m fault seems to be occurring primarily by rise of the and reach as high as 2450 m. The ﬁ rst ﬁ ve km of the footwall, rather than by fall of the hangingwall, as hike are through the Gigilos beds, the massive white commonly assumed. This distinction is possible here marbles in the Plattenkalk unit that we say at Day 1, because the geomorphic features allow us to measure Stop 8. The impressive cliffs along the sides of the displacements relative to sea level. This evidence of gorge offer impressive exposures of folds developed footwall rise during normal faulting suggests that in the platy member of the Plattenkalk. The platy horizontal extension may be related to basal accretion

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: alo, .. ad oefl, .. 18) Optical (1981). J.L. Rosenfeld, and W.D., Carlson, 643-655. niae ta te wr acee b underplating by accreted were they nappes that sub-detachment indicates the of metamorphism LT HP- The island. the beneath depth at underplating or . Tosn SN, n Kse, . (2002). M. Küster, annealing zone in partial high Theye, pressure-low zircon temperature and rocks fossil a E., from data S.N., Thermobarometric Seidel, Thomson, B., T., Stöckhert, M.R., Brix, Publications 17,517-527. Robertson, Mediterranean and J.E., A.H.F.,eds. Dixon, In: reconstruction. tectonic their and Hellenic Aegean south-east the the in of Nappes Correlation (1984). M. Bonneau, de laSociétégéologique deFrance égéen. l’Arc dans et méridional Péloponnèse en externes>> cristallins <

Special Publications45,265-283. eds., D., Dietrich, and M.P. Coward, In: Mediterranean. western the of Kinematics (1989). S.D. Knott, and Dewey, J.F., Helman, J.L., Turco, E., Hutton, D.W.H., Tectonics orogens. of collapse Extensional Dewey,J.F.(1988). Paläont. Abh. Kreta. auf Präneogens des Geologie der Stand Zum (1975). Creutzburg,E. Seidel, and N., Exploration Mining and (IGME), Athens Geological of Institute 1:200,000). (1977). (scale Crete of Map A. Geological General Tataris, and Seidel, J., Papastamatiou, J.W., Meulenkamp, C.W., Drooger, N., Creutzburg, implications. Geology metamorphic kinetics: growth aragonite-calcite topotactic of determination asua, . 20) Te etnc eeomn of development tectonic The (2001). C. Fassoulas, p., Heraklio. Crete. of Geology the to Guide Field (2000). C. Fassoulas, Crete, Greece. of of island exhumation the in rocks temperature low- high-pressure and extension stacking Postnappe (1994). D. Mountrakis, and Kilias, A., C., Fassoulas, Paläont. Abh. (1972). Geologie der Talea Ori/Kreta. Epting, J., Kudrass, H-R., Leppig, U., and Schafer, A. the of kinematics southern Hellenic Arc. Recent to Miocene Late the for implications Messinian Crete: early on rotations Post counter-clockwise (1998). J.H. Veen, ten and C.G., Langereis, W., Krijgsman, C.E., Duermeijer, phase. rotation Planetary ScienceLetters young and rapid a for the evidenceAegeangeodetic and paleomagnetic arc: Spakman, and C.G., W.evolutionNeogene (2000). of P.Th,Langereis, Meijer, M., Nyst, C.E., Duermeijer, lie Tectonics Alpine Natural History Museum of Crete, Publ., Crete, of Museum History Natural 89,615-638, 7,1123-1139. 149,363-383. 141,259-285. Tectonics . Gooia Scey London, Society, Geological . Tectonophysics 13,127-138. 176,509-525. Neues. Jb.Geol. Neues. Neues Jb. Geol. 298,177-189. ora of Journal at and Earth 21-05-2004, 14:36:21 104 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

a Neogene basin at the leading edge of the active Jiménez-Munt, I., Sabadini, R., Gardi, A., and Bianco, European margin: the Heraklion basin, Crete, Greece. G. (2003). Active deformation in the Mediterranean Journal of Geodynamics 31, 49-70. from Gibraltar to Anatolia inferred from numerical Fortuin, A.R., and Peters, J.M. (1984). The Prina modeling and geodetic and seismological data. Complex in eastern Crete and its relationship to Journal of Geophysical Research 108, doi:10.1029/ possible Miocene strike-slip tectonics. Journal of 2001JB001544. Structural Geology 6, 459-476. Jolivet, L., Goffe, B., Monie, P., Truffert-Luxey, C., Patriat, M & Bonneau, M. (1996). Miocene Frydas, D., and Keupp, H. (1996). Biostratigraphical detachment in Crete and exhumation P-T-t paths results in Late Neogene deposits of NW Crete, of high-pressure metamorphic rocks. Tectonics 15, Greece, based on calcareous nannofossils. Berliner 1129-1153. geowiss. Abh, E 18, 169-189. Karakitsios, V. (1987). Sur la signiﬁ cation de la Fytrolakis, N. (1980). The geological structure of série de Trypali dans la région de Sellia en Crète Crete: Problems, observations, and conclusions. occidentale (Grèce). CR Acad. Sci. Paris, 304 (II/3), Habil. Thesis, Nat. Techn. Univ. Athens, 143 p. 123-128.

Greiling, R. (1982). The metamorphic and structural Kastens, K.A. (1991). Rate of outward growth of evolution of the Phyllite-quartzite nappe of western the Mediterranean Ridge accretionary complex. Crete. Journal of Structural Geology 4, 291-297. Tectonophysics 199, 25-50.

Hall, R., Audley-Charles, M.G., and Carter, D.J. Kilias, A., Falalakis, G., and Mountrakis, D. (1999). (1984). The signiﬁ cance of Crete for the evolution Cretaceous - Tertiary structures and kinematics of of the Eastern Mediterranean. In: Dixon, J.E., and the Serbomacedonian metamorphic rocks and their Robertson, A.H.F. (eds) The Geological Evolution relation to the exhumation of the Hellenic hinterland of the Eastern Mediterranean. Geological Society, (Macedonia, Greece). International Journal of Earth London, Special Publications 17, 499-516. Sciences, 88, 513-531.

Hall, R., and Audley-Charles, M.G. (1983). The Kissel, C., and Laj, C. (1988). The Tertiary structure and regional signiﬁ cance of the Talea Ori, geodynamical evolution of the Aegean arc: a Crete. Journal of Structural Geology 5, 167-179. paleomagnetic reconstruction. Tectonophysics 146, 183-201. Hatzfeld, D., Martinod, J., and Bastet, G. (1997). An analog experiment for the Aegean to describe the Knapmeyer, M., and Harjies, H.P. (2000). Imaging contribution of gravitational potential energy. Journal crustal discontinuities and the downgoing slab of Geophysical Research 102, 649-659. beneath western Crete. Geophysical Journal International 143, 1-21. Huguen, C., Mascle, J., Chaumillon, E., Woodside, J.M., Benkhelil, J., Kopf, A., and Volskonkaia,k Kopp, K., and Ott, E. (1977). Spezialkartierungen

A. (2001). Deformation styles of the eastern im Umkreis neuer Fossilfunde in Tripali und n° 2 Volume - from B16 to B33 Mediterranean Ridge and surroundings from Tripolitzakalken Westkretas. Neues Jb. Geol. Paläont. combined swatch mapping and seismic reﬂ ection Monat., 4, 217-238. proﬁ ling. Tectonophysics 343, 21-47. Kopf, A., Mascle, J., and Klaeschen, D. (2003). Jackson, J. (1994). Active tectonics of the Aegean The Mediterranean Ridge: A mass balance across region. Annual Reviews of Earth and Planetary the fastest growing accretionary complex on Earth. Science 22, 239-271, Journal of Geophysical Research, 108, doi:10.1029/ 2001JB000473.

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: rh, . Kufan G, ou, . Rctr D., zur Daten Richter,Neue F.(1983). Heinritzi, and O., Förster, H., Kozur, G., Kauffmann, J., Krahl, 221-225. Greece. Sea, Aegean Cyclades, type the Cordilleran in of (1984). complexes A. core Feenstra, Metamorphic and G., Banga, G.S., Lister, nappes. Geology Hellenic the and backstop Ridge Lemeur, D., and Pascal, G. N., (2002). The Mediterranean Chamot-Rooke, S.J., Lallemant, X., Pichon, Le London Sea. Aegean The (1981). J. Angelier, and X., Pichon, Le area. Mediterranean Eastern the neotectonic Tectonophysics the to of key a evolution system: trench and arc Hellenic The (1979). J. Angelier,and X., Pichon, Le host the of strength minerals. creep the on based approach thermobarometric A Crete: from rocks metamorphic ﬂ of Küster, M., and Stöckhert, B. (1997). Density changes Freiburg. Exkursion. – Paleontologischen– GeologischUniversitaet Kreta Institue zur Fuhrer (1980). S.E. Kuss, 207. Gesellschaft geologischen deutschen der des (Greichenland). Bau Deckenstapels kretischen im Ori Talea der Stellung Zur (1988). R. Krahl, J., Richter, D., Forster, O., Kozur, H., and Hall, 1147-1166. (Griechenland). Kreta Insel der auf Trypali-Gruppe der und Phyllit-Gruppe der Lagerung tektonischen zur und Biostratigraphie otiuin t Mnrlg ad Petrology 465-478. and implications. Mineralogy and to Contributions modelling, data, experimental new calcite: to Transformation aragonite polycrystalline (1993). of kinetics R.A. Yund, and M., Liu, uid inclusions in high-pressure low-temperature high-pressure in inclusions uid Philosophical Transactions of the Royal Society,TransactionsPhilosophical Royal the of , 300,357-372. 186,111-125. Lithos 60,1-42. 41,151-167. elgsh Rundschau Geologische Geology 3, 191- 139, Zeitschrift Marine 114, 72, 12,

ceze DP (98. oe eak o the basins. Planetary ScienceLetters on sedimentary remarks of Some development (1978). D.P. McKenzie, Royal Astronomical Society the of region. tectonics Mediterranean Active (1972). D.P. McKenzie, Geophysical Research Caucasus. and Mediterranean eastern the in dynamics and kinematics plate on constraints System Position Global (2000). al. et S. McClusky, Marine Geology data. geophysical from deduced Sea Mediterranean eastern the of mantle upper and crust the of state and properties Physical (1984). C. Stobbe, and J., Makris, sounding. seismic deep Tectonophysics from region of mantle Aegean upper the and crust The (1978). J. Makris, . Lbrl J, n Mnagoi LF (1982). L.F. Thommeret, Montaggioni, J., and Tectonophysics J., Thommeret, Laborel, Y., P.A., Pirazzoli, arc. Recent vertical motions in the Cretan segment to of the Hellenic Miocene Late van On and (1994). W.A. G.J., Wamel, Zwaan, der van J.E., Meulenkamp, Miocene. Tectonophysics Middle late the since Crete of evolution geodynamic the and zone subduction Hellenic the On (1988). E. Strating, Hoogerduyn and W., Spakman, J.E., Meulenkamp, Wortel,vanM.J.R., Wamel, W.A., Paleontology, and University Geology of Athens, A, 32. of Department the of Crete. of Neogene the to Guide Field (1979). H. Böger, and H.A., Georgiadou-Jonkers, E., Dikeoulia, M., Dermitzakis, J.E., Meulenkamp, Tectonics deformation. and stress of pattern horizontal the analysis of model A region: Aegean the of dynamics Present-day P.Th.Meijer,(1997). Wortel, and M.J.R. Tectonophysics 16,879-895. 46,269-284. 86,27-43. 146,203-215. 55,217-254. 234,53-72. 105,5695-5719. epyia Junl f the of Journal Geophysical 40,25-32. 30,109-185. Publications at and Earth ora of Journal 21-05-2004, 14:36:23 EXHUMATION OF HIGH-PRESSURE METAMORPHIC ROCKS WITHIN AN ACTIVE CONVERGENT MARGIN, CRETE, GREECE B32

Platt, J.P. (1986). Dynamics of orogenic wedges 209. and the uplift of high-pressure metamorphic rocks. Geological Society of America Bulletin 97, 1037- Spakman, W., Wortel, M.J.R., and Vlaar, N.J. (1988). 1053. The Hellenic subduction zone: a tomographic image and its geodynamic implications. Geophysical Pomoni-Papaioannou, F., and Karakitsios, V. Research Letters 15, 60-63. (2002). Facies analysis of the Trypali carbonate unit (Upper Triassic) in central-western Crete (Greece): Stöckhert, B., Wachmann, M., Küster, M., and an evaporite formation transformed into solution- Bimmermann, S. (1999). Low effective viscosity collapse breccias. Sedimentology 49, 1113-1132. during high pressure metamorphism due to dissolution precipitation creep: the record of HP-LT Robertson, A.H.F., Clift, P., Degnan, P.J., and Jones, metamorphic carbonates and siliciclastic rocks from G. (1991). Palaeogeographic and paleotectonic Crete. Tectonophysics 303, 299-319. evolution of the eastern Mediterranean Neotethys. Palaeogeography, Palaeoclimatology, and Ten Veen, J.H., and Meijer, P.T. (1998). Late Miocene Palaeoecology 87, 289-343. to Recent tectonic evolution of Crete (Greece): geological observations and model analysis. Tectonophysics 298, 191-208. Royden, L.H. (1993). The tectonic expression of slab pull at continental convergent boundaries. Tectonics Ten Veen, J.H., and Postma, G. (1999a). Neogene 12, 303-325. tectonics and basin ﬁ ll patterns in the Hellenic outer- arc. Basin Research 11, 223-241. Sannemann, W., and Seidel, E. (1976). Die Trias- Ten Veen, J.H., and Postma, G. (1999b). Roll-back Schichten von Rawdoucha/NW-Kreta. Ihre Stellung controlled vertical movements of outer-arc basins of im kreitischen Deckenbau. Neues Jb. Geol. Paläont. the Hellenic subduction zone (Crete, Greece). Basin Mh. 4, 221-228. Research 11, 243-266.

Seidel, M. (2003). Tectono-sedimentary evolution of Theye, T., and Seidel, E. (1991). Petrology of low- middle Miocene supra-detachment basins (western grade high-pressure metapelites from the External Crete, Greece). Ph.D. Dissertation, University of Hellenides (Crete, Peloponnese): A case study with Köln. 116 pages. attention to sodic minerals. European Journal of Mineralogy 3, 343-366. Seidel, E., Okrusch, m., Kreuzer, H., Raschka, H., and Harre, W. (1976) Eo-alpine metamorphism Theye, T., Seidel, E., and Vidal, O. (1992). in the uppermost unit of the Cretan nappe system Carpholite, sudoite, and chloritoid in low-grade high- – petrology and geochronology – Part 1. The Lendas pressure metapelites from Crete and the Peloponnese. area (Asteroussia Mountains). Contributions to European Journal of Mineralogy 4, 487-507. Mineralogy and Petrology 57, 259-275. Theye, T., and Seidel, E. (1993). Uplift-related

Seidel, E., Kreuzer, H., and Harre, W. (1982). A Late retrogression history of argonite marbles in Western n° 2 Volume - from B16 to B33 Oligocene/Early Miocene high pressure belt in the Crete. Contributions to Mineralogy and Petrology External Hellenides. Geologisches Jahrbuch E23, 114, 349-356. 165-206. Theye, T., and Seidel, E. (2001). Bauxite in Schwarz, S., and Stöckhert, B. (1996). Pressure hochdruckmetamorphen Einheiten der externen solution in siliciclastic HP-LT metamorphic rocks Helleniden. Braunschweiger geowiss. Arb. 24, 225- - constraints on the state of stress in deep levels of 233. accretionary complexes. Tectonophysics, 255, 203-

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Volume n° 2 - from B16 to B33 B32 - B32 B32 Leaders: J.M. Rahl J.M. Leaders: rocks of Crete, Greece: implications for the speed of speed the for implications Greece: Crete, of rocks Thermochronology of the high-pressure metamorphic Thomson, S.N., Stöckhert, B., and Brix, M.R. (1998a). ree rpd xuain y uyn escape. buoyant by exhumation rapid Greece: Crete, of rocks metamorphic high-pressure Micocene (1999). M.R. Brix, and B. Stöckhert, S.N., Thomson, Publishers.) Thermonchronology P.,F.Corte, De and (eds). system. subduction Hellenic the of evolution tectonic post-Eocene the Greece: for Implications Crete, of Unit Tectonic Uppermost the of M.R. (1998b). Apatite ﬁ Brix, and H., Rauche, B., Stöckhert, S.N., Thomson, tectonic processes. Geology 1725 (lwr Academic (Kluwer 187-205. , ssion-track thermochronology Advances in Fission-Trackin Advances 26,259-262. In: Vanhaute, den In:

region. and slab detachment in the Mediterranean-Carpathian Wortel,Spakman, and W.M.J.R., Subduction (2000). 419-435. models. wedge of in dependence extension Rheological (1999). S.D. Willett, Erosion London, SpecialPublications,154,p.87-107. and Flow Ductile Willet, & G.S. (eds) Lister, S.D. M.T., Brandon, U., Ring, Science Exhumation Processes: Normal Faulting, Normal Processes: Exhumation 290,1910-1917. Gooia Society, Geological . Tectonophysics 21-05-2004, 14:36:26 305, Back Cover: ﬁ eld trip itinerary

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