Chatterjee, Nilanjan and Nicolaysen, Kirsten (2012): An intercontinental correlation of the mid-Neoproterozoic Eastern Indian tectonic zone; evidence from the gneissic clasts in Elan Bank conglomerate, Kerguelen Plateau

Leg/Site/Hole:
ODP 183
ODP 183 1137
Identifier:
2012-071289
georefid

10.1007/s00410-011-0699-z
doi

Creator:
Chatterjee, Nilanjan
Massachusetts Institute of Technology, Department of Earth Sciences, Atmospheric and Planetary Sciences, Cambridge, MA, United States
author

Nicolaysen, Kirsten
Whitman College, United States
author

Identification:
An intercontinental correlation of the mid-Neoproterozoic Eastern Indian tectonic zone; evidence from the gneissic clasts in Elan Bank conglomerate, Kerguelen Plateau
2012
Contributions to Mineralogy and Petrology
Springer International, Heidelberg - New York, International
163
5
789-806
The Kerguelen Plateau is a submarine, Cretaceous Large Igneous Province in the southern Indian Ocean. Drilling on Elan Bank, a western salient of the Kerguelen Plateau, yielded a approximately 26 m section of fluvial conglomerate intercalated with basalt. Chemical dating of monazite within garnet and matrix monazite in metapelitic clasts from the conglomerate indicates that high-grade metamorphism of the pelitic protolith occurred between 785+ or - 2 and 694+ or -18 Ma. A calculated P-T pseudosection indicates that the observed core-to-inner rim compositional zoning in garnet is consistent with P/T decrease from 10.2 kb/760 degrees C to 6.2 kb/560 degrees C. In an Early Cretaceous paleogeographic reconstruction, the Elan Bank drill site is located on a SSW continuation of the Eastern Indian Tectonic Zone (EITZ), a 876-784 Ma, NNE-SSW metamorphic belt with sinistral shear zones in eastern India. The retrograde P-T path of the Elan Bank metapelitic clast overlaps with that of the EITZ metapelite, and the Elan Bank monazite chemical dates and previously determined 824-675 Ma U-Pb isotope monazite dates by the TIMS method are remarkably similar to the monazite chemical dates from the EITZ metapelites and high-grade metamorphic rocks from the eastern margin of the Eastern Ghats Belt. Based on the demonstrable affinity of metamorphic, geochronologic, and spatial data, this study concludes that the EITZ was likely a continuous, approximately 1,800-km-long tectono-metamorphic belt in the Rodinia supercontinent stretching from eastern India through the Eastern Ghats to the basement of Elan Bank and probably to the Rayner Complex of East Antarctica. Copyright 2011 Springer-Verlag
English
Serial
Coverage:Geographic coordinates:
North:-56.5000
West:68.0536East: 68.0536
South:-56.5000

Geochronology; Igneous and metamorphic petrology; absolute age; Antarctica; Asia; clastic rocks; conglomerate; correlation; crystal chemistry; dates; East Antarctica; Eastern Ghats; Eastern Indian tectonic zone; Elan Bank; electron probe data; geochemistry; geologic barometry; geologic thermometry; Ghats; India; Indian Ocean; Indian Peninsula; Kerguelen Plateau; Leg 183; lithostratigraphy; major elements; metamorphic rocks; metamorphism; metapelite; metasedimentary rocks; minor elements; monazite; Neoproterozoic; Ocean Drilling Program; ODP Site 1137; P-T conditions; petrology; phosphates; Precambrian; Proterozoic; Rodinia; sedimentary rocks; textures; U/Pb; upper Precambrian;

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