Arc-Related Pyroxenites Derived from a Long-Lived Neoarchean Subduction System at the Southwestern Margin of the Cuddapah Basin: Geodynamic Implications for the Evolution of the Eastern Dharwar Craton, Southern India

2019 ◽  
Vol 127 (5) ◽  
pp. 567-591
Author(s):  
Abhinay Sharma ◽  
Rohit Kumar Giri ◽  
N. V. Chalapathi Rao ◽  
Waliur Rahaman ◽  
Dinesh Pandit ◽  
...  
Keyword(s):  
Dharwar Craton ◽  
Southern India ◽  
Cuddapah Basin ◽  
Eastern Dharwar Craton ◽  
Southwestern Margin ◽  
Subduction System

Petrogenesis of an alkaline lamprophyre (camptonite) with ocean island basalt (OIB)-affinity at the NW margin of the Cuddapah basin, eastern Dharwar craton, southern India

2019 ◽  
Vol 196 (2) ◽  
pp. 149-177 ◽  
Author(s):  
Rohit Kumar Giri ◽  
Praveer Pankaj ◽  
N.V. Chalapathi Rao ◽  
Ramananda Chakrabarti ◽  
Dinesh Pandit
Keyword(s):  
Mantle Source ◽  
Dharwar Craton ◽  
Southern India ◽  
Striking Similarity ◽  
Cuddapah Basin ◽  
Eastern Dharwar Craton ◽  
Calc Alkaline ◽  
Western Margin ◽  
Ocean Island ◽  
Alkaline Lamprophyres

We report petrology and geochemistry (including Sr and Nd isotopes) of a fresh lamprophyre at Ankiraopalli area at the north-western margin of Paleo-Mesoproterozoic Cuddapah basin, eastern Dharwar craton, southern India. Ankiraopalli samples possess a typical lamprophyre porphyritic-panidiomorphic texture with phenocrysts of kaersutite and diopside set in a plagioclase dominant groundmass. Combined mineralogy and geochemistry classify it as alkaline lampro- phyre in general and camptonite in particular. Contrary to the calc-alkaline and/or shoshonitic orogenic nature portrayed by lamprophyres occurring towards the western margin of the Cuddapah basin, the Ankiraopalli samples display trace element composition revealing striking similarity with those of ocean island basalts, Italian alkaline lamprophyres and highlights an anorogenic character. However, the87 Sr/86 Srinitial (0.710316 to 0.720016) and εNdinitial (– 9.54 to – 9.61) of the Ankiraopalli lamprophyre show derivation from an 'enriched' mantle source showing long term enrichment of incompatible trace elements and contrast from those of (i) OIB, and (ii) nearby Mahbubnagar alkaline mafic dykes of OIB affinity. Combining results of this study and recent advances made, multiple mantle domains are identified in the Eastern Dharwar craton which generated distinct Mesoproterozoic lamprophyre varieties. These include (i) Domain I, involving sub-continental lithospheric mantle source essentially metasomatized by subduction-derived melts/fluids (represented by orogenic calcalkaline and/or shoshonitic lamprophyres at the Mudigubba, the Udiripikonda and the Kadiri); (ii) Domain II, comprising a mixed sub-continental lithospheric and asthenospheric source (represented by orogenic-anorogenic, alkaline to calc-alkaline transitional lamprophyres at the Korakkodu), and (iii) Domain III, representing a sub-continental lithospheric source with a dominant overprint of an asthenospheric (plume) component (represented by essentially alkaline lamprophyres at the Ankiraopalli). Our study highlights the varied mantle source heterogeneities and complexity of geodynamic processes involved in the Neoarchean-Paleo/Mesoproterozoic evolution of the Eastern Dharwar craton.

Petrology and petrogenesis of Mesoproterozoic lamproites from the Ramadugu field, NW margin of the Cuddapah basin, Eastern Dharwar craton, southern India

Lithos ◽  
2014 ◽  
Vol 196-197 ◽  
pp. 150-168 ◽  
Author(s):  
N.V. Chalapathi Rao ◽  
Alok Kumar ◽  
Samarendra Sahoo ◽  
A.N. Dongre ◽  
Debojit Talukdar
Keyword(s):  
Dharwar Craton ◽  
Southern India ◽  
Cuddapah Basin ◽  
Eastern Dharwar Craton

Mesoproterozoic 40Ar–39Ar ages of some lamproites from the Cuddapah Basin and Eastern Dharwar Craton, southern India: implications for diamond provenance of the Banganapalle Conglomerates, age of the Kurnool Group and Columbia tectonics

2021 ◽  
pp. SP513-2020-247
Author(s):  
Alok Kumar ◽  
Debojit Talukdar ◽  
N. V. Chalapathi Rao ◽  
R. Burgess ◽  
B. Lehmann
Keyword(s):  
Dharwar Craton ◽  
Southern India ◽  
Cuddapah Basin ◽  
Eastern Dharwar Craton ◽  
Break Up ◽  
Radiometric Dates

AbstractWe report Mesoproterozoic 40Ar–39Ar (whole-rock) ages of lamproites from (i) the Ramadugu field (R4 dyke : 1434 ± 19 Ma and R5 dyke: 1334 ± 12 Ma) and the Krishna field (Pochampalle dyke: 1439 ± 3 Ma and Tirumalgiri dyke: 1256 ± 12 Ma) from the Eastern Dharwar Craton (EDC) and (ii) the Garledinne (1433 ± 8 Ma) and the Chelima (1373 ± 6 Ma) dykes from within the Paleo-Mesoproterozoic Cuddapah Basin, southern India. The ages reported for the Ramadugu and Tirumalgiri lamproites constitute their first radiometric dates. Ages of the Pochampalle and the Chelima lamproites from this study are broadly comparable to their previously reported 40Ar–39Ar (phlogopite) ages of c. 1500 Ma and 1418 ± 8 Ma, respectively. The ages of all these lamproites are much older than those of the (i) c. 1.1 Ga kimberlites from the Wajrakarur and Narayanpet fields of the EDC and (ii) c. 1.09 Ga lamproitic dykes at Zangamarajupalle which intrude the Cumbum Formation of the Cuddapah Basin. However, the age of the Tirumalgiri lamproite (c. 1256 Ma) is similar to that of the Ramannapeta lamproite (c. 1224 Ma) within the Krishna field. Our study provides evidence for protracted ultrapotassic (lamproitic) magmatism from c. 1.43 to 1.1 Ga over a widespread area (c. 2500 km2) in and around the Cuddapah Basin and the EDC. Implications of the obtained new ages for the diamond provenance of the Banganapalle Conglomerates, the age of the Kurnool Group and for the timing of break-up of the Paleo-Mesoproterozoic supercontinent of Columbia/Nuna are explored.

scholarly journals Petrogenesis of Proterozoic Lamproites and Kimberlites from the Cuddapah Basin and Dharwar Craton, Southern India: a Reply

2005 ◽  
Vol 46 (6) ◽  
pp. 1081-1084 ◽  
Author(s):  
N. V. CHALAPATHI RAO ◽  
S. A. GIBSON ◽  
D. M. PYLE ◽  
A. P. DICKIN ◽  
J. DAY
Keyword(s):  
Dharwar Craton ◽  
Southern India ◽  
Cuddapah Basin
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