Contrasting kinematics of brittle-shears within the Salem–Attur and Bhavani shear zone, south India: Tectonic implications

Abstract

We document kinematics and rheological behaviour of brittle shears (~50 cm wide) postdating solid-state tectonic fabric in the Salem–Attur (SASZ) and Bhavani (BSZ) shear zone that constitute a Paleoproterozoic (~2500 Ma) suture juxtaposing disparate granulite blocks in south India. We constrain brittle deformation mechanisms from established relationship between changing orientation of deflected strain marker (quartz vein) and foliation within the shear band with respect to their orientation outside the shear band. Quartz c-axis orientation in charnockite (host lithology) and phyllonite (reworked charnockite) from the SASZ show presence of mixed basal 〈a〉 (low-T) and prism 〈a〉 (high-T) slip, and single basal 〈a〉 slip mechanism, respectively. This suggests considerable cooling of the granulite block prior to the onset of brittle shearing. Distribution of strain parameters – effective shear strain (Γ), shear strain (γ), stretch K2 along intermediate strain axis Y – from margin to the centre of the shear band, show peaked distribution with a single maximum at the shear zone centre. This implies rheological-weakening/strain-softening induced localizing shear zone character. Kinematically heterogeneous strain distribution during brittle shearing varies from transpression dominated for the BSZ to transpression-to-transtension switchover for the SASZ. Demonstrably, contrasting cooling-exhumation, hitherto unexplored, characterizes post-accretionary tectonics along the paleo-suture zone.

This is a preview of subscription content, access via your institution.

Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Figure 11
Figure 12

References

  1. Bhaskar Rao Y J, Chetty T R K, Janardhan A S and Gopalan K 1996 Sm–Nd and Rb–Sr ages and P–T history of the Archaean Sittampundi and Bhavani layered meta-anorthosite complexes in Cauvery Shear zone, south India: Evidence for Neoproterozoic reworking of Archaean crust; Contrib. Mineral. Petrol. 125 237–250.

    Google Scholar 

  2. Bartlett J M, Dougherty-Page J S, Harris N B W, Hawkesworth C J and Santosh M 1998 The application of single zircon evaporation and model Nd ages to the interpretation of polymetamorphic terrains: An example from the Proterozoic mobile belt of south India; Contrib. Mineral. Petrol. 131 181–195.

    Google Scholar 

  3. Beaumont C, Nguyen M H, Jamieson R A and Ellis S 2006 Crustal flow modes in large hot orogens; Geol. Soc. London, Spec. Publ. 268 91–145.

    Google Scholar 

  4. Behera B M, Waele B D, Thirukumaran V, Sundaralingam K, Narayanan S, Sivalingam B and Biswal T K 2019 Kinematics, strain pattern and geochronology of the Salem–Attur shear zone: Tectonic implications for the multiple sheared Salem–Namakkal blocks of the Southern Granulite terrane, India; Precamb. Res. 324 32–61.

    Google Scholar 

  5. Bhadra S and Nasipuri P 2017 Tectonothermal evolution of garnet-bearing quartzo-feldspathic gneiss from the Moyar shear zone, south India: Implications for Neoarchean accretionary tectonics; Lithos 274–275 1–18.

    Google Scholar 

  6. Bhadra B K 2000 Ductile shearing in Attur shear zone and its relation with Moyar shear zone, south India; Gond. Res. 3 361–369.

    Google Scholar 

  7. Bhaskar Rao Y J, Janardhan A S, Vijaya Kumar T, Narayana B L, Dayal A M, Taylor P N and Chetty T R K 2003 Sm–Nd model ages and Rb–Sr isotopic systematics of charnockites and gneisses across the Cauvery Shear Zone, southern India: Implications for the Archean–Neoproterozoic Terrane Boundary in the Southern Granulite Terrain; In: Tectonics of Southern Granulite Terrain: Kuppam–Palani Geotransect (ed.) Ramakrishnan M, Geol. Soc. India Memoir 50 297–317.

  8. Biswal T K, Thirukumaran V, Ratre K, Bandyapadhaya K, Sundaralingam K and Mondal A K 2010 A study of mylonites from parts of the Salem–Attur Shear Zone (Tamil Nadu) and its tectonic implications; J. Geol. Soc. India 75 128–136.

    Google Scholar 

  9. Chetty T R K, Bhaskar Rao Y J and Narayana B L 2003 A structural cross-section along Krishnagiri–Palani Corridor, Southern Granulite Terrain of India; In: Tectonics of Southern Granulite Terrain, Kuppam–Palani Geotransect (ed.) Ramakrishnan M, Geol. Soc. India 50 255–277.

  10. Chetty T R K 1996 Proterozoic shear zones in Southern Granulite Terrain; In: The Archaean and Proterozoic Terrains in Southern India within East Gondwana India (eds) Santos M and Yoshida M, Gond. Res. Gr. Mem. 3 77–89.

  11. Clark C, Collins A S, Timms N E, Kinny P D, Chetty T R K and Santosh M 2009 SHRIMP U–Pb age constraints on magmatism and high-grade metamorphism in the Salem Block, southern India; Gond. Res. 16 27–36.

    Google Scholar 

  12. D’Cruz E, Nair P K R and Prasannakumar V 2000 Palghat gap – a dextral shear zone from the south Indian Granulite Terrain; Gond. Res. 3 21–31.

    Google Scholar 

  13. Dias R and Rebeiro A 1994 Constriction in a transpressive regime: An example in the Iberian branch of the lbero-Armorican arc; J. Struct. Geol. 16 1543–1554.

    Google Scholar 

  14. Drury S A, Harris N B W, Holt R W, Reeves-Smith G J and Wightman R T 1984 Precambrian tectonics and crustal evolution in southern India; J. Geol. 92 3–20.

    Google Scholar 

  15. Faccenda M, Gerya T V and Chakraborty S 2008 Styles of post-subduction collisional orogeny: Influence of convergence velocity, crustal rheology and radiogenic heat production; Lithos 103 257–287.

    Google Scholar 

  16. Faccenda M and Mancktelow S 2010 Fluid flow during unbending: Implications for slab hydration, intermediate-depth earthquakes and deep fluid subduction; Tectonophys. 494 149–154.

    Google Scholar 

  17. Fletcher J M and Bartley J M 1994 Constrictional strain in a non-coaxial shear zone: Implications for fold and rock fabric development, central Mojave metamorphic core complex, California; J. Struct. Geol. 16 555–570.

    Google Scholar 

  18. Flinn D 1962 On folding during three dimensional progressive deformation; Quart. J. Geol. Soc. 118 385–433.

    Google Scholar 

  19. Fossen H and Tikoff B 1993 The deformation matrix for simultaneous simple shearing, pure shearing and volume change, and its application to transpression–transtension tectonics; J. Struct. Geol. 15 413–422.

    Google Scholar 

  20. Friend C R L and Nutman A P 1991 SHRIMP U–Pb geochronology of the Closepet granite and Peninsular gneisses, Karnataka, south of India; J. Geol. Soc. India 38 357–368.

    Google Scholar 

  21. Ghosh J G, De Wit M J and Zartman R E 2004 Age and tectonic evolution of Neoproterozoic ductile shear zones in the Southern Granulite Terrain of India, with implications for Gondwana studies; Tectonics 23 1–38.

    Google Scholar 

  22. Horsman E and Tikoff B 2007 Constraints on deformation path from finite strain gradients; J. Struct. Geol. 29 256–272.

    Google Scholar 

  23. Hull J 1988 Thickness–displacement relationships for deformation zones; J. Struct. Geol. 10 431–435.

    Google Scholar 

  24. Hunter N J R, Weinberg R F, Wilson C J L and Law R D 2018 A new technique for quantifying symmetry and opening angles in quartz c-axis pole figures: Implications for interpreting the kinematic and thermal properties of rocks; J. Struct. Geol. 112 1–6.

    Google Scholar 

  25. Jain A K, Singh S and Manickavasagam 2003 Intracontinental shear zones in the southern granulite terrane: Their kinematics and evolution; Geol. Soc. India Memoir 50 225–253.

    Google Scholar 

  26. Jiang H, Lee C A, Morgan J K and Ross C H 2015 Geochemistry and thermodynamics of an earthquake: A case study of pseudotachylites within mylonite granitoids; Earth Planet. Sci. Lett. 430 235–248.

    Google Scholar 

  27. Magni V, Faccenna C, Hunen J V and Funiciello F 2013 Delamiantion vs. break-off: The fate of continental collision; Geophys. Res. Lett. 40 285–289.

    Google Scholar 

  28. Means W D 1984 Shear zones of types I and II and their significance for reconstruction of rock history; Geol. Soc. Am. Abs. 16 50.

    Google Scholar 

  29. Means W D 1995 Shear zones and rock history; Tectonophys. 247 157–160.

    Google Scholar 

  30. Meiβner B, Deters P, Srikantappa C and Köhler H 2002 Geochronological evolution of the Moyar, Bhavani and Palghat shear zones of southern India: Implications for east Gondwana correlations; Precamb. Res. 114 149–175.

    Google Scholar 

  31. Mukhopadhyay D, Kumar S P, Srinivasan R and Bhattacharya T 2003 Nature of the Palghat–Cauvery lineament in the region south of Namakkal, Tamil Nadu: Implications for terrane assembly in the south Indian granulite province; In: Tectonics of Southern Granulite Terrain, Kuppam–Palani Geotransect (ed.) Ramakrishnan M, Geol. Soc. India Memoir 50 279–296.

  32. Naha K and Srinivasan R 1996 Nature of Moyar and Bhavani shear zone with a note on its implication on the tectonics of the southern Indian peninsula shield; Proc. Acad. Sci. (Earth Planet. Sci.) 105 173–189.

    Google Scholar 

  33. Nair P K R, Prasannakumar V and Thomas M 1981 Structure of the western termination of the Bhavani lineament; J. Geol. Soc. India 22 285–291.

    Google Scholar 

  34. Neumann B 2000 Texture development of recrystallised quartz polycrystals unraveled by orientation and misorientation characteristics; J. Struct. Geol. 22 1695–1711.

    Google Scholar 

  35. Passchier W 1984 The generation of ductile and brittle shear bands in a low-angle mylonite zone; J. Struct. Geol. 6 273–281.

    Google Scholar 

  36. Peucat J J, Mahabaleswar B and Jayananda M 1993 Age of younger tonalitic magmatism and granulite metamorphism in the South Indian transition zone (Krishnagiri area): Comparison with older Precambrian gneisses from Hassan–Gorur area; J. Metamorph. Geol. 11 879–888.

    Google Scholar 

  37. Prasannakumar V and McCaig A 2016 Reactivation and strain localisation in Bhavani Shear Zone, South India; J. Geol. Soc. India 88 421–432.

    Google Scholar 

  38. Prasannakumar V and Lloyd G E 2007 Development of crystallographic lattice preferred orientation and seismic properties in Bhavani shear zone, southern India; J. Geol. Soc. India 70 282–296.

    Google Scholar 

  39. Prasannakumar V and Lloyd G E 2010 Application of SEMEBSD to regional scale shear zone analysis: A case study of the Bhavani shear zone, south India; J. Geol. Soc. India 75 183–201.

    Google Scholar 

  40. Pratheesh P, Prasannakumar V and Praveen K R 2013 Magnetic fabrics in characterization of magma emplacement and tectonic evolution of the Moyar Shear Zone, south India; Geosci. Front. 4 113–122.

    Google Scholar 

  41. Raith M, Srikantappa C, Buhl D and Koehler H 1999 The Nilgiri enderbites, south India: Nature and age constraints on protolith formation, high grade metamorphism and cooling history; Precamb. Res. 98 129–150.

    Google Scholar 

  42. Ramakrishnan M 2003 Craton-mobile belt relations in Southern Granulite Terrain; In: Tectonics of Southern Granulite Terrain, Kuppam–Palani Geotransect (ed.) Ramakrishnan M, Geol. Soc. India Memoir 50 1–24.

  43. Ramsay J G 1967 Folding and Fracturing of the rocks; McGraw Hill, New York, 568p.

    Google Scholar 

  44. Ramsay J G 1980 Shear zone geometry: A review; J. Struct. Geol. 2 83–99.

    Google Scholar 

  45. Ratheesh-Kumar R T, Santosh M, Yang Q Y, Ishwar-Kumar C, Chen N S and Sajeev K 2016 Archean tectonics and crustal evolution of the Biligiri Rangan Block, southern India; Precamb. Res. 275 406–428.

    Google Scholar 

  46. Santosh M and Sajeev K 2006 Anticlockwise evolution of ultrahigh-temperature granulites within the continental collision zone in southern India; Lithos 92 447–464.

    Google Scholar 

  47. Santosh M, Maruyama S and Sato K 2009 Anatomy of a Cambrian suture in Gondwana: pacific-type orogeny in southern India; Gond. Res 16 321–341.

    Google Scholar 

  48. Satheeshkumar R and Prasannakumar V 2009 Fabric evolution in Salem–Attur shear zone, south India and its implications on the kinematics; Gond. Res. 16 37–44.

    Google Scholar 

  49. Sato K, Santosh M, Tsunogae T, Chetty T R K and Hirata T 2011 Laser ablation ICP mass spectrometry for zircon U–Pb geochronology of metamorphosed granite from the Salem Block: Implication for Neoarchean crustal evolution in southern India; J. Min. Petrol. Sci. 106 1–12.

    Google Scholar 

  50. Sawant A D, Gupta S, Clark C and Misra S 2017 The Rauer–Rengali connection in the Indo-Antarctica amalgam: Evidence from structure, metamorphism and geochronology; Geol. Soc. London, Spec. Publ. 457 171.

    Google Scholar 

  51. Sorcar N, Hoppe U, Dasgupta S and Chakraborty S 2014 High-temperature cooling histories of migmatites from the High Himalayan Crystallines in Sikkim, India: Rapid cooling unrelated to exhumation; Contrib. Mineral. Petrol. 167 957.

    Google Scholar 

  52. Sundaralingam K, Biswal T K and Thirukumaran V 2017 Strain analysis of the Salem–Attur shear zone of Southern Granulite Terrane around Salem, Tamil Nadu; J. Geol. Soc. India 89 5–11.

    Google Scholar 

  53. Tikoff B and Fossen H 1993 Simultaneous pure and simple shear: The unified deformation matrix; Tectonophys. 217 267–283.

    Google Scholar 

  54. Vitale S and Mazzoli S 2016 From finite to incremental strain: Insights into heterogeneous shear zone evolution; In: Ductile shear zones from micro- to macro-scales (eds) Mukherjee S and Mulchrone K F, John Wiley & Sons, USA, 306p.

  55. Vitale S and Mazzoli S 2008 Heterogeneous shear zone evolution: The role of shear strain hardening/softening; J. Struct. Geol. 30 1363–1395.

    Google Scholar 

  56. Vitale S and Mazzoli S 2009 Finite strain analysis of a natural ductile shear zone in limestones: Insights into 3-D coaxial vs. non-coaxial deformation partitioning; J. Struc. Geol. 31 104–113.

    Google Scholar 

  57. Vitale S and Mazzoli S 2010 Strain analysis of heterogeneous ductile shear zones based on planar markers; J. Struct. Geol. 32 321–329.

    Google Scholar 

Download references

Acknowledgements

AC acknowledges the financial support from Pondicherry University and DST-SERB, Grant-in-Aid No. SERB/F/5928/2018-2019, for carrying out geological fieldwork, sample preparation and analysis. Ritabrata is acknowledged for his support during EBSD analyses. The authors are grateful to the reviewers for their critical suggestions and constructive comments. Prof Saibal Gupta is thanked for editorial handling.

Author information

Affiliations

Authors

Corresponding author

Correspondence to Subhadip Bhadra.

Additional information

Supplementary materials pertaining to this article are available on the Journal of Earth Science Website (http://www.ias.ac.in/Journals/Journal_of_Earth_System_Science).

Communicated by Saibal Gupta

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (DOCX 1189 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Ananth, C., Bhadra, S. & Goswami, A. Contrasting kinematics of brittle-shears within the Salem–Attur and Bhavani shear zone, south India: Tectonic implications. J Earth Syst Sci 129, 62 (2020). https://doi.org/10.1007/s12040-019-1331-2

Download citation

Keywords

  • Strain marker
  • rheology
  • EBSD analysis
  • Salem–Attur shear zone
  • Southern Granulite Terrain