Journals / Turkish Journal of Earth Sciences / 2009 / Cilt: 18 - Sayı: 2

Two-and-Three-Dimensional Crustal Thickness of the Eastern Pontides (NE Turkey)

Pages
225–238
Publication Date
2009-02-01
DOI
—
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

We calculated the maximum crustal thickness of 43.8 km in the studied region by using the gravity inversion method, which also showed that crustal thickness increases from north to south.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:The Eastern Pontide orogenic belt is divided into three subzones (northern, southern and axial zones) based on present lithologies and facies associations.
📊
Key Findings & Data:NE-SW-, NW-SE- and E-W-trending fault systems, which play an important role in palaeotectonics and neotectonics of the Eastern Pontides, separate these zones.
💡
Conclusion & Impact:We calculated the maximum crustal thickness of 43.8 km in the studied region by using the gravity inversion method, which also showed that crustal thickness increases from north to south.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Eastern Pontides · crustal structure · moho depth

Abstract

The Eastern Pontide orogenic belt is divided into three subzones (northern, southern and axial zones) based on present lithologies and facies associations. NE-SW-, NW-SE- and E-W-trending fault systems, which play an important role in palaeotectonics and neotectonics of the Eastern Pontides, separate these zones. Three different methods were used to estimate the Moho depth from observed gravity value, namely (i) empirical relationship between Moho depth and Bouguer anomaly; (ii) spectral analysis of the radial wave number and; (iii) by the gravity inversion method. Power spectrum, a statistical approach, is a widely used technique to determine the depth of geological sources successfully. The empirical linear relations between the Bouguer anomalies and seismically determined crustal thicknesses have been used to compute depths to the Conrad and Moho discontinuities, which are consistent with the average depths obtained from the power spectrum method. The crustal structure was also determined from the inversion of a Bouguer anomaly profile along longitude 39°. Gravity inversion results are consistent with those obtained from the empirical relations and power spectrum methods. We calculated the maximum crustal thickness of 43.8 km in the studied region by using the gravity inversion method, which also showed that crustal thickness increases from north to south.

Özet

The Eastern Pontide orogenic belt is divided into three subzones (northern, southern and axial zones) based on present lithologies and facies associations. NE-SW-, NW-SE- and E-W-trending fault systems, which play an important role in palaeotectonics and neotectonics of the Eastern Pontides, separate these zones. Three different methods were used to estimate the Moho depth from observed gravity value, namely (i) empirical relationship between Moho depth and Bouguer anomaly; (ii) spectral analysis of the radial wave number and; (iii) by the gravity inversion method. Power spectrum, a statistical approach, is a widely used technique to determine the depth of geological sources successfully. The empirical linear relations between the Bouguer anomalies and seismically determined crustal thicknesses have been used to compute depths to the Conrad and Moho discontinuities, which are consistent with the average depths obtained from the power spectrum method. The crustal structure was also determined from the inversion of a Bouguer anomaly profile along longitude 39°. Gravity inversion results are consistent with those obtained from the empirical relations and power spectrum methods. We calculated the maximum crustal thickness of 43.8 km in the studied region by using the gravity inversion method, which also showed that crustal thickness increases from north to south.

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Cite This Article

MADEN, N., GELİŞLİ, K., BEKTAŞ, Y. E. &. O. (2009). Two-and-Three-Dimensional Crustal Thickness of the Eastern Pontides (NE Turkey). Turkish Journal of Earth Sciences, Cilt: 18 - Sayı: 2, 225–238. https://ajindex.com/articles/384743

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References (12)

  1. ADAMIA, S., LORDKIPANIDZE, M.B. & ZAKARIADZE, G.S. 1977. Evolution of an active continental margin as exemplified by the Alpine history of the Caucasus. Tectonophysics 40, 183–189.
  2. AL-LAZKI, A., SANDVOL, E., SEBER, D., TÜRKELLİ, N., MOHAMAD, R. & BARAZANGI, M. 2003. Tomographic Pn velocity and anisotropy structure beneath the Anatolian plateau (Eastern Turkey) and the surrounding regions. Geophysical Research Letters 30, 8043. ATEŞ, A., BİLİM, F. & BÜYÜKSARAÇ, A. 2005. Curie point depth investigation of Central Anatolia, Turkey. Pure and Applied Geophysics 162, 357–371.
  3. BANSAL, A.R. & DIMRI, V.P. 2001. Depth estimation from the scaling power spectral density of nonstationary gravity profile. Pure and Applied Geophysics 158, 799–812.
  4. BANSAL, A.R., DIMRI, V.P. & SAGAR, G.V. 2006. Depth estimation from gravity data using the maximum entropy method (MEM) and the multi taper method (MTM). Pure and Applied Geophysics 163, 1417–1434
  5. BEKTAŞ, O. 1986. Paleostress trajectories and polyphase rifting in arc- back arc of Eastern Pontides. Mineral Research and Exploration Institute (MTA) Bulletin 103/104, 1–15.
  6. BEKTAŞ, O. & ÇAPKINOĞLU, Ş. 1997. Neptunian dikes and block tectonics in the Eastern Pontide magmatic arc, NE Turkey, implications for the kinematics of the Mesozoic basins. Geosound 30, 451–461.
  7. BEKTAŞ, O. & GÜVEN, İ.H. 1995. Alaskan appinitic type ultramafic and mafic complexes as the root zone of the Eastern Pontide magmatic arc (NE Turkey).International, Symposium on the Geology of the Black Sea Region, Proceedings, 189–196.
  8. BEKTAŞ, O., ŞEN, C., ATICI, Y. & KÖPRÜBAŞI, N. 1999. Migration of the upper Cretaceous subduction-related volcanism towards the back- arc basin of the Eastern Pontide magmatic arc (NE Turkey). Geological Journal 34, 95–106.
  9. BHATTACHARYA, B.K. 1966. Continuous spectrum of the total magnetic anomaly due to a rectangular prismatic body. Geophysics 31, 97– 121. BHATTACHARYYA, B.K. & LEU, L.K. 1975. Spectral analysis of gravity and magnetic anomalies due to two-dimensional structures. Geophysics 40, 993–1013.
  10. BHATTACHARYYA, B.K. & LEU, L.K. 1977. Spectral analysis of gravity and magnetic anomalies due to rectangular prismatic bodies. Geophysics 42, 41–50.
  11. BOZKURT, E. 2001. Neotectonics of Turkey – a synthesis. Geodinamica Acta 14, 3–30.
  12. BURKE, K. & ŞENGÖR, A.M.C. 1986. Tectonic escape in the evolution of the continental crust. In: BARAZANGI, M. (ed), Reflection Seismology, Continental Crust, Geodynamic Series, 14. American Geophysical Union Sp