Miocene tectonic motions in the Central Anatolia Plateau interior: A seismo-structural study in the Tuz Gölü Basin (poster)

(1)

Acknowledgements

We thank the European Science Foundation (ESF) and the NetherlandsOrganization for Scientiﬁc Research (NWO) for their ﬁnancial support, through the VU Amsterdam and the Vertical Anatolia Movement Project enclosed in TopoEurope.

References

Special thanks go to Fabrizio Pepe and the members of the VAMP team for discussions and unpublished information

[1] Mitra, S., and J. Namson (1989), Equal-area balancing, American Journal of Science, 289 (5), 563. [2] Sclater, J., and P. Christie (1980), Continental stretching: an explanation of the post-mid-Cretaceous subsidence of the central North Sea basin, Journal of Geophysical Research, 85 (B7), 3711–3739. [3] Steckler, M., and A. Watts (1978), Subsidence of the Atlantic-type continental margin oﬀ New York, Earth and Planetary Science Letters, 41 (1), 1–13.

Miocene evolutionary model of the Tuz Gölü Basin

Present

Top Messinian

Top Tortonian

Top Paleogene

Uplift Stresses Subsidence Cretaceous metamorphics Paleozoic Paleogene Messinian Tortonian Plio-Q Legend NNE NE NE Regional subsidence

Broad sag basin Tectonic subsidence (partially fault-related)Extensional tectonics - TGF formation Continued subsidence (partially fault-related)Compressional tectonics - SAT formation Regional surface upliftExtensional tectonics

Vertical vs. Horizontal

Fig. 8. Subsidence rates vs. restoration values 5.3 7.3 11.6 Plio-Q Messinian Tort onian Paleog. TGF _SAT Shortening (-) Extension (+) Horizontal deformation (km) Tectonic subsidence Basement subsidence Extension (+) / Shortening (-) 12 10 8 6 4 2 1 0 12 10 8 6 4 2 0 ? ? ? 0 Ma Ma Subsidence in site C Subsidence (km) -6 -3 -9 0 a b Fig. 7. Subsidence curves

Subsidence curves

Tectonic max Tectonic mean Tectonic min Basement mean Hiatus Non-deposition Hiatus Non-deposition 5.3 7.3 11.6 Plio-Q 11.6 7.3 5.3 Messinian Tort onian Plio-Q Messinian Tort onian 12 10 8 6 4 2 0 1 0 -1 Age (Ma) E ? ? ? ? ? ? 12 10 8 6 4 2 0 1 0 -1 D epth (K m) Age (Ma) TG6 12 10 8 6 4 2 0 1 0 -1 D epth (K m) Age (Ma) D ? ? ? 12 10 8 6 4 2 0 1 0 -1 D epth (K m) Age (Ma) A ? ? ?

Results

1. Tuz Gölü is a broad not fault-related Miocene basin

1.a. Units 1 to 3 (Miocene): i) continue both sides of fault systems ii) show no basin terminations

1.b. Unit 4 (Paleogene) thickens toward the SW

2. Tortonian Extension << Late Messinian Shortening >> Plio-Q Extension

2.a. Hitherto unreported thrust during Unit 2 (Messinian) (displacement > 8 km)

3. Primary subsidence signal is tectonic

4. Extension/shortening whilst overall subsidence

Table 1. TG6 well data, seismic unit deﬁnition and seismic velocity

Tortonian Paleog ene Messinian Upper Cretac. Plio-Q Epoch

(Ma) Seism. UnitFormation Lithology Velocity(m/s)

0 m 350 584 783 1330 1560 5.3 7.3 11.6 56 Metamorphic rocks Clay, marls & silts Limestones & marly limestones Marly carbonates & clays N U2 NU1 Cihanbe yli Fm. Eskipola tı Fm. Unit 4 Unit 3 Unit 2 Unit 1 Unit 5 Poorly consolidated limestones 4690 3810 3585 2770 2035

Fig.6. Restoration of line A

Restoration

2 km 2 km 2 km 2 km 2 km 2 km P(r) P(r) P(II) P(Sc) P(II) P(I) P(I) 120 m 9750 m 8275 m 8370 m 3225m

Retrodeformation Top of Paleogene ; β = 1,003

Retrodeformation Top of Tortonian ; β = 1,005

Retrodeformation pre-Top of Messinian ; β = 0,535

Topography removal by simple vertical shear

Present-day simplification of line AKV 90603

NE SW NE SW 55 m 85 m

Retrodeformation Base of Pliocene ; β = 1,012

LEGEND Cretaceous Messinian Tortonian Paleogene Pliocene - Quaternary Fault Stratigraphic contact P(II) - Point II P(I) - Point I

P(r) - Reference for reconstruction - Pin P(Sc) - Site A of subsidence curve Referent points: A F E D C B 1 2 2 3 4 5 7 8 6 2 km V = H Present - -Base Pliocene Top Messinian Top Tortonian 0 0 85 55 -8370120 -8275 P(II) P(I) 0 Top Paleogene Displacement (m) Table 2. Restored horizontal displacements Fig. 4. Depth-converted seismic line A (NE-SW oriented)

Fig. 5. Depth-converted seismic line G (NNW-SSE oriented)

SW Line A NE 1 2 3 Km 2 km H = V NNW Line G SSE 1 2 3 Km 4 km 2H = V

Fig. 3. Geologic and data map

Şereflikoçhisar-Aksaray Ridge TGF TGF TGF SAT SAT (SAT) TGF SAT TGF TGF TGF (TGF) SAT SFS 38ºN 38ºN 39ºN 39ºN 34ºE 34ºE 33ºE 33ºE Alt�nekin Cihanbeyli Aksaray Ortaköy Şereflikoçhisar Line G Line E Line F Line A Line B Line D Line C A B C E TG6 D TURKEY Ankara Km 0 40 Cretaceous Paleozoic Plio-Miocene Paleogene CVP volcanics Pleisto-Q metamorphics WELL Subsidence curve site TG 6 _{SEISMIC LINE} X Legend

Seismic interpretation

Astenosphere Mantle Lithosphere Crust 40-50 Km 5-35 Km 100’s Km 2-8 Km Endorheism Endorheism 40-80 Km 0 10 50 100 150 Km S.L.

Fig.2. Plateaux cartoon

Fig.1. Simpliﬁed structural map of Turkey

■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ▲ ▲ ▲ ▲ ▲ ▲ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■_■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ▲ ▲ ▲ ▲ _▲ _{▲ ▲ ▲} ▲ ▲ ▲ ▲ ▲ ▲ 36ºE 32ºE 40ºE 40ºN 38ºN 36ºN 40ºN 38ºN 36ºN Km 0 100 200 300 Antalya Mut Istanbul Sinop Erzincan Aydιn

36ºE 32ºE 40ºE 36ºE 32ºE 40ºE 40ºN 38ºN 36ºN 40ºN 38ºN 36ºN

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_AURIDE

_S

CEN

TRAL

ANATO

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PON

TIDES

Plateaux features

Q1. What type of tectonic movements occurred?

Q2. Which structures accommodated the movements? When?

Q3. What is the genetic nature of the CAP?

A1. Regional subsidence since Tortonian - Younger regional uplift

Faults create minor modulations

A2. (i) Pre─Miocene: Sultalhani Fault System (SFS) - Extensional

(ii) Tortonian: Tuz Gölü Fault (TGF) - Extensional

(iii) Latest Miocene: Şereﬂikoçhisar─Aksaray (SAT) - Shortening

A3. Type of motions point to mantle-supported uplift

Orientation/type of structures points to shortening-related uplift

Tectonics of the central domain during buildup of the Central Anatolia Plateau (CAP)

Research Questions

Research Answers

Central Anatolia micro-Plateau (CAP) interior and the Tuz Gölü Basin

The CAP is the perfect natural laboratory for the study of the complex interactions between

deep thermo-mechanical and surface erodibility-climatical processes acting during plateau formation

The Tuz Gölü Basin is a major representative amongst the Late Cenozoic or younger basins in the interior of the Central Anatolia Plateau; unravelling the structural pattern of deformation as well as the accurate timing of the tectonic motions and events undergone by this basin

will give relevant constrains on the mode and genetic nature of the CAP and information on plateaux genesis elsewhere

Vertical Anatolian Movement Project (VAMP)

Studying the CAP we aim at increase the temporal and spatial resolution of plateau-building processes, by determining

(i) Miocene to recent deformations, uplift and strain partitioning;

(ii) continental sedimentary archives linked with long-term climate changes; (iii) patterns of erosional exhumation; and

(iv) the geophysical characteristics of the deep mantle/lithosphere

EGU2012-12244

TS4.4/G6.1/GD3.8/GM3.3

Miocene tectonic motions in the Central Anatolia Plateau interior: a seismo-structural study in the Tuz Gölü Basin

(1) Dept. of Tectonics, Vrije Universiteit, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands

(2) Dept. of Earth Sciences, Faculty of Geosciences, Utrecht University, P.O. Box 80.021, 3508 TA Utrecht, The Netherlands

(3) Dept. of Geotechnology, Delft University of Technology, Stevinweg 1, 2628 CN Delft, The Netherlands

(4) Dept. of Geological Engineering, Hacettepe University, Beytepe, 06800 Ankara, Turkey

David Fernández-Blanco

(1,2)

Giovanni Bertotti

(1,3)

Attila Çiner

(4)

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_{est. 2002}

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This poster participates in OSP