Mid-Miocene strike-slip in continental Greece

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1. Introduction

MID MiOCENE STRIKE SLIP IN CONTINENTAL GREECE

A. Faucher(1); F. Gueydan(1); M. Jolivet(2); M. Alsaif(1)

- (1) Géosciences Montpellier, UMR5243CNRS, Université de Montpellier, rue Eugène Bataillon, 34095 Montpellier, France, [email protected];

(2) Laboratoire Géosciences Rennes, CNRS-UMR6118, Université Rennes 1, avenue Général Leclerc, 35042, Rennes, France.

2. Structural Data - North Basin

5. Conclusion

4. Apatite Fission Track Data

3. Structural Data - South Basin

Complex Ophiolitique Ionan Zone Gavrovo - Tripolitza

Pinde Parnassos - Zone Ghiona Zone Beotian Pelagonia (sens large)

Gneiss Schistes Schistes Bassin Miocene Schistes Bleus (CBU) Legend ADRIA PINDE Flysch N G14_G15 G05 G03 G23 G16 G13 G08 G09 G11

10 AFT ages show a phase of generalized Eo-Oligocene extension. Two ages (G11-G16) located on the roof of N150 faults have a last phase of exhumation at 15Ma.

Distance along the profil (Km)

AFT A ge (M a) 20 40 60 80 100 200 300 400 0 Pelagonia

Fault A.F.T Cyclades (C.B.U)

A.F.T Pelagonia

2 family faults: - N150 Faults associated with larger amount of sedimentation indicating syn-kinematical filling of the basin Mid- Miocene activity

- E-W faults associated to Plio-Quaternary time

a a’

- Mid-Miocene basin does not extend beyond Pelagonian Fault predates the functioning of the fault

- Miocene bedding in the basin are sub-horizontal, even close the fault

deposition after the fault activity

- Faults and folds analysis demonstrates the existence of a major dextral slip kinematic

=> Dextral strike slip activity of the Pelagonian fault during mid-Miocene time.

Classical view of the geodynamic evolution of Greece:1/ Classical back-arc extension with N150 normal faults 2/ followed by mainly N50 dextral strike-slip faults (Gulf of Evvia and Corinth) since 5 Ma marking the impact of the NAF in the tectonic system

BUT

Some published structural data in the Cyclades show that N50 dextral

strike-slip were already active during mid-Miocene time (Kokkalas and

Aydin, 2013; Brun et al; 2016)

Legend

Flysch Ophiolite Blueschists ADRIA

Age AFT (Ma)

Structural

Normal fault Normal fault in this study N 25 km 0-10 10-20 30-40 40-50 20-30 > 50

T

A A’ A _A’ 1. Eo-Oligocene: A generalized extension over the entire Aegean domain

2. Mid-Miocene time: implying the coeval activity of N50 dextral strike slip and N150 normal faults.

.AFT show Mid Miocene

Pelagonian fault activity

1 -> 2Interplay between the

extension related to the retreat of the slab and the onset at around 15 Ma of westward extrusion of Anatolia

3. Plio-Pleistocene: Activity of E-W normal fault

-> Interplay between NAF and

back arc extension and formation of the Corinth and Evvia rifts system

Mid Miocene Pelagonian Fault

Legend Miocene basin Marbles & schists Undifferentiated sediment & Metamorphic rocks Flysch Ophiolites Blueschists

PINDOS

ADRIA

Age AFT (Ma)

0-10 10-20 20-30 Structural N150 Normal fault N90 Normal fault Pelagonian fault PEL A GONIA N 25 km Pelagonian Fault Pelagonian fault

N

Pelagonian (strike-slip ?) Fault

Fault from Royden and Papanikolaou, 2011 (except for the Pelagonian fault)

Kokkalas and Aydin, 2013

G16 G11 Deposit âge Reset age (+ last exhumation stage) North Mid Miocene Basin South Mid Miocene Basin Deposit âge 20° 14° 33° 74° 36° 22° 21° 35° 35° 20° 31° 28° 62° 30° 12° 31° 50° 86° 47° 10° 28° 11° 59° 71° 48° 12° 20° 14° 30° 27° 30° 39° 28° 55° 20° 61° 36° 56° 37° 18° 26° 72° 68° 15° 46° 33° 26° 42° 17° 26° 23° 30° 11° 20° 6° 13° 25° 35°25° <10° 20° 19° 43° 23° 15° 30° 21°

N

5km

a

a’

Legend Miocene Basin Tria-Jurassic Sediment Ultrabasic Rock Permo-carboniferous sediment Pelagonia Pindos Foliation Fault

{

SSE NNW 2 Km

Constrain the potential activity of dextral strike slip faulting during Mid-Miocene in Continental Greece.

> Focus on Evvia and Attic to understand the tectonic context of the deposition of two mid-Miocene basins.

Acknowledgements: This project has received funding from the European Union's EU Framework Programme for Research and Innovation Horizon 2020 under Grant Agreement No 674899.

References:

Brun J.P., Faccenna C., Gueydan F., Sokoutis D., Philippon M., Kydonakis K. et Gorini C., (2016). The two-stage Aegean extension, from localized to distributed, a result of slab rollback acceleration. NRC Research Press 53, 1142–1157.

doi: 10.1139/cjes-2015-0203

Kokkalas, S., Aydin, A., 2013. Is there a link between faulting and magmatism in the south-central Aegean Sea? Geological Magazine 150, 193–224. https://doi.org/10.1017/S0016756812000453

Royden, L.H., Papanikolaou, D.J., 2011. Slab segmentation and late Cenozoic disruption of the Hellenic arc: DISRUPTION OF THE HELLENIC ARC. Geochemistry, Geophysics, Geosystems 12, n/a-n/a. https://doi.org/10.1029/2010GC003280

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2

Pole Miocene Basin Bedding N150 fault plane E-W fault plane N150 striation

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2

EviaBlueschist Unit (E.B.U) Almyropotamos Unit (A.U) Triassic Sediment Paleozoïc Metamorphic rock Miocene Basin Cretacious Sediment Jurrassic Sediment with volcanic rock Ultrabasique Rock Antiform Synforme Strike-slip fault Thrust fault Legend Pelagonia C.B .U 30° 55° 35° 35° 10° 35° 15° 80° 45° 15° 35° 80° 40° 55° 30° 30° 40° 15° 35° 30° 35° 25° 25° 50° 35° 37° 25° 22° 17° Fig. A A