<abstract xmlns="http://www.w3.org/1999/xhtml">Numerous soft-sediment deformation structures occur within the Proterozoic Bhander Limestone of an intracratonic sag basin in a 750 m long section along the Thomas River, near Maihar, central India. Part of these deformation structures have most probably a non-seismic origin, but other structures are interpreted as resulting from earthquake-induced shocks. These seismic structures are concentrated in a 60 cm thick interval, which is interpreted as three stacked seismi-tes. These three seismites are traceable over the entire length of the section. They divide the sedimentary succession in a lower part (including the seismites) deposited in a hypersaline lagoon, and an upper open-marine (shelf) part. Most of the soft-sediment deformations outside the seismite interval occur in a lagoonal intraclastic and muddy facies association.The SSDS within the seismite interval show a lateral continuity. They record simultaneous fluidisation and liquefaction. The bases of each of the three composing seismite bands are defined by small-scale shear folds, probably recording an earthquake and aftershocks.The presence of the three seismite bands at the boundary between the lagoonal and the overlying open-marine oolitic facies association suggests that the seismic event also triggered basin subsidence.</abstract>

Numerous soft-sediment deformation structures occur within the Proterozoic Bhander Limestone of an intracratonic sag basin in a 750 m long section along the Thomas River, near Maihar, central India. Part of these deformation structures have most probably a non-seismic origin, but other structures are interpreted as resulting from earthquake-induced shocks. These seismic structures are concentrated in a 60 cm thick interval, which is interpreted as three stacked seismi-tes. These three seismites are traceable over the entire length of the section. They divide the sedimentary succession in a lower part (including the seismites) deposited in a hypersaline lagoon, and an upper open-marine (shelf) part. Most of the soft-sediment deformations outside the seismite interval occur in a lagoonal intraclastic and muddy facies association.The SSDS within the seismite interval show a lateral continuity. They record simultaneous fluidisation and liquefaction. The bases of each of the three composing seismite bands are defined by small-scale shear folds, probably recording an earthquake and aftershocks.The presence of the three seismite bands at the boundary between the lagoonal and the overlying open-marine oolitic facies association suggests that the seismic event also triggered basin subsidence.

Seismic and non-seismic soft-sediment deformation structures in the Proterozoic Bhander Limestone, central India

Department of Geological Sciences, Jadavpur University, Kolkata-700 032, India

Department of Earth Sciences, IIT Bombay, Powai, Mumbai 400 076, India

Institute of Geology, Adam Mickiewicz University, Maków Polnych 16, 61-606 Poznan, Poland. e-mail:

Geologos

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Numerous soft-sediment deformation structures occur within the Proterozoic Bhander Limestone of an intracratonic sag basin in a 750 m long section along the...

Seismic and non-seismic soft-sediment deformation structures in the Proterozoic Bhander Limestone, central India

Publié en ligne: 08 juil. 2014

Pages: 89 - 103

Reçu: 11 janv. 2014

Accepté: 10 avr. 2014

DOI: https://doi.org/10.2478/logos-2014-0008

Mots clés
seismites, soft-sediment deformation structures, basin subsidence, Bhander Limestone, Proterozoic, India

© 2014 Subir Sarkar et. al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Seismic and non-seismic soft-sediment deformation structures in the Proterozoic Bhander Limestone, central India

Publié en ligne: 08 juil. 2014

Pages: 89 - 103

Reçu: 11 janv. 2014

Accepté: 10 avr. 2014

DOI: https://doi.org/10.2478/logos-2014-0008

Mots clésseismites, soft-sediment deformation structures, basin subsidence, Bhander Limestone, Proterozoic, India

© 2014 Subir Sarkar et. al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Mots clés
seismites, soft-sediment deformation structures, basin subsidence, Bhander Limestone, Proterozoic, India