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Generalized tectonic map of central and peninsular India showing location of major structural zones and boundaries. AD, Aravalli–Delhi fold belt; B, Bundelkhand massif; BC, Bastar craton; CIS, Central Indian Shear Zone; CITZ, Central Indian Tectonic Zone; DC, Dharwar craton; EG, Eastern Ghats; KD, Kotri–Dongargarh belt; KN, Karnataka nucleus; M, Madras block; MC, Marwar craton; MR, Madurai block; N, Nilgiri block; SC, Singhbhum craton; SK, Sakoli fold belt; SMB, Sausar mobile belt; SONA, Son-Narmada subzone; T, Trivandrum block; TF, Tapti fault; M, B, A, P, C, Moyar–Bavali, Bhavani, Attur, Palghat, and Cauvery shear zones. Significantly modified from Acharyya and Roy (2000).
Source publication
Eight Re–Os ages from six molybdenite samples representative of the Cu–Mo–Au mineralization at the giant Malanjkhand deposit in Madhya Pradesh were obtained using ID-NTIMS. These data provide a clear Late Archean–Early Paleoproterozoic age for this deposit and by implication for its calc-alkaline granitoid host. Among other diverse models, the orig...
Contexts in source publication
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... is a complex mosaic of sutured terranes that includes Archean and Proterozoic rocks of lowto high-grade metamorphism. Three early Archean cores, the Karnataka, Bastar, and Singhbhum, have been recognized in peninsular India ( Fig. 1), and their sedimentary-magmatic rocks have a geologic history extending back to 3.6-3.5 Ga. Archean and Proterozoic rocks surround these cores, and continental scale orogenic belts ( Fig. 1) contain enclaves and lithotectonic structures that preserve poorly defined episodes of ductile-brittle deformation. Among the less well-studied ...
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... rocks of lowto high-grade metamorphism. Three early Archean cores, the Karnataka, Bastar, and Singhbhum, have been recognized in peninsular India ( Fig. 1), and their sedimentary-magmatic rocks have a geologic history extending back to 3.6-3.5 Ga. Archean and Proterozoic rocks surround these cores, and continental scale orogenic belts ( Fig. 1) contain enclaves and lithotectonic structures that preserve poorly defined episodes of ductile-brittle deformation. Among the less well-studied belts is the Central Indian Tectonic Zone (CITZ; Acharyya, 2001), which connects peninsular India to the mainland and overprints the Malanjkhand batholith containing the giant Malanjkhand ...
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... contain enclaves and lithotectonic structures that preserve poorly defined episodes of ductile-brittle deformation. Among the less well-studied belts is the Central Indian Tectonic Zone (CITZ; Acharyya, 2001), which connects peninsular India to the mainland and overprints the Malanjkhand batholith containing the giant Malanjkhand Cu-Mo-Au deposit (Fig. 1). Near complete lack of robust geochronology hampers both correlations between units within the CITZ and understanding of processes that brought these terranes together. Interpretations for timing range from multi-phase development of the CITZ from 2.5 to 1.0 Ga ( Roy et al., 2001) to a younger Mesoproterozoic 1.0 Ga history related to ...
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... lies along the southern margin of the Central Indian Shear Zone (CIS; Jain et al., 1991), a brittle-ductile shear zone that forms the mylonitic southern boundary of the Central Indian Tectonic Zone (CITZ; Radhakrishna, 1989;Acharyya and Roy, 2000;Acharyya, 2001Acharyya, , 2003. Although the CIS is recognized as an old and stable suture ( Fig. 1), as also is the Sausar mobile belt (SMB), present-day reactivation of faults along the northern CITZ (Son-Narmada subzone, SONA) render the region seismically active (Shanker, 1991). There is almost no geochronology for the CITZ, which can be traced for 1600 km and attains widths of 200 km. The CITZ is covered to the west by the ...
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... as also is the Sausar mobile belt (SMB), present-day reactivation of faults along the northern CITZ (Son-Narmada subzone, SONA) render the region seismically active (Shanker, 1991). There is almost no geochronology for the CITZ, which can be traced for 1600 km and attains widths of 200 km. The CITZ is covered to the west by the Deccan basalts ( Fig. 1), but nevertheless, it has been recognized as an important continental-scale tectonic zone of Proterozoic age and a locality for important sutures (Yedekar et al., 1990;Jain et al., 1991;Mishra et al., 2000). The CITZ contains the not yet unraveled record of a collision that brought together two cratons, the northern Indian craton or ...
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... 1990;Jain et al., 1991;Mishra et al., 2000). The CITZ contains the not yet unraveled record of a collision that brought together two cratons, the northern Indian craton or Bundelkhand protocontinent to the north and the southern Indian craton or Dharwar protocontinent to the south. The latter includes the Dharwar, Bastar, and Singhbhum cratons ( Fig. 1). Others have used the term "Central Indian Shield" to refer to a protocontinent comprised of the Bastar and Bundelkhand cratons with an intervening and periodically reactivated tectonic block (CITZ) designated as a major mobile belt (Divakara ...
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... the Central Indian Tectonic Zone (CITZ); (2) the Sakoli fold belt (SK) to the southwest which forms a triangular wedge of supracrustal rocks that disappears beneath Deccan basalt cover; and (3) the Kotri-Dongargarh belt (KD) to the south, which hosts the Nandgaon volcanics and the intrusive Dongargarh granitoids in the northwestern Bastar craton (Fig. 1). Contacts between these belts constitute major structural discontinuities about which relatively little is known. Even the most recent publications provide little agreement on regional geologic relationships and correlations (e.g., compare Acharyya and Roy, 2000, Fig. 2; Bhargava and Pal, 2000, Fig. 1; Bhowmik and Roy, 2003, Fig. 2; ...
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... in the northwestern Bastar craton (Fig. 1). Contacts between these belts constitute major structural discontinuities about which relatively little is known. Even the most recent publications provide little agreement on regional geologic relationships and correlations (e.g., compare Acharyya and Roy, 2000, Fig. 2; Bhargava and Pal, 2000, Fig. 1; Bhowmik and Roy, 2003, Fig. 2; Divakara Rao et al., 2000, Fig. 1; Mishra et al., 2000, Fig. 7;Ramachandra and Roy, 2001, Figs. 1 and 2;Roy et al., 2002, Fig. 1; Sikka and Nehru, 1997, Fig. 12), in itself rendering the context of Malanjkhand controversial. Detailed mapping of key localities and boundaries is essential to understanding ...
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... these belts constitute major structural discontinuities about which relatively little is known. Even the most recent publications provide little agreement on regional geologic relationships and correlations (e.g., compare Acharyya and Roy, 2000, Fig. 2; Bhargava and Pal, 2000, Fig. 1; Bhowmik and Roy, 2003, Fig. 2; Divakara Rao et al., 2000, Fig. 1; Mishra et al., 2000, Fig. 7;Ramachandra and Roy, 2001, Figs. 1 and 2;Roy et al., 2002, Fig. 1; Sikka and Nehru, 1997, Fig. 12), in itself rendering the context of Malanjkhand controversial. Detailed mapping of key localities and boundaries is essential to understanding the relationships between these three terranes and to placing ...
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... Even the most recent publications provide little agreement on regional geologic relationships and correlations (e.g., compare Acharyya and Roy, 2000, Fig. 2; Bhargava and Pal, 2000, Fig. 1; Bhowmik and Roy, 2003, Fig. 2; Divakara Rao et al., 2000, Fig. 1; Mishra et al., 2000, Fig. 7;Ramachandra and Roy, 2001, Figs. 1 and 2;Roy et al., 2002, Fig. 1; Sikka and Nehru, 1997, Fig. 12), in itself rendering the context of Malanjkhand controversial. Detailed mapping of key localities and boundaries is essential to understanding the relationships between these three terranes and to placing Malanjkhand in a modern tectonic context relative to ...
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... provide little agreement on regional geologic relationships and correlations (e.g., compare Acharyya and Roy, 2000, Fig. 2; Bhargava and Pal, 2000, Fig. 1; Bhowmik and Roy, 2003, Fig. 2; Divakara Rao et al., 2000, Fig. 1; Mishra et al., 2000, Fig. 7;Ramachandra and Roy, 2001, Figs. 1 and 2;Roy et al., 2002, Fig. 1; Sikka and Nehru, 1997, Fig. 12), in itself rendering the context of Malanjkhand controversial. Detailed mapping of key localities and boundaries is essential to understanding the relationships between these three terranes and to placing Malanjkhand in a modern tectonic context relative to ...
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... Sakoli fold belt (SK in Fig. 1) is in tectonic contact with the Amgaon gneiss complex to the north, east, and south. In this region the Amgaon basement consists of high-grade supracrustal gneisses and migmatites, with Cr-bearing metaultramafics and pre-Sakoli supracrustal assemblages of quartzite, kyanite and sillimanite schists, calc-silicate rocks and marbles, and ...
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... rocks of the Kotri-Dongargarh belt (KD in Fig. 1) lie unconformably on the Amgaon gneiss complex, which is composed of augen gneiss, banded gneiss and migmatites, and amphibolites in the Dongargarh-Malanjkhand region. The supracrustal rocks are dominated by greenschist facies Nandgaon volcanic sequences. Presently accepted belief is that this belt includes both the Malanjkhand and ...
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... and a conjugate set of structures with an ENE trend. A few of the scattered Cu-Mo-Au prospects in the batholith are hosted in local mylonites and shear zones that have been subsequently segmented by ENE faults with the northern segments successively rotated to the northwest, and some mineral occurrences have an ENE strike (Bhargava and Pal, 2000, Fig. 1). This array of structural features could be attributed to oblique convergence, a tectonic setting favoring formation of large Cu-Au deposits (e.g., Mungall, 2002). The structurally diverse Cu-Mo-Au prospects and the deforma- Fig. 7. Compilation of ∼2.5 Ga ages (largely U-Pb) in peninsular India and mainland India immediately north of ...
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... boundary between the Archean Dharwar craton and the largely Proterozoic Madurai and Trivandrum blocks to the south is comprised of a complicated array of shear zones ( Radhakrishna et al., 2003) and the intervening high-grade Nilgari and Madras crustal provinces (Fig. 1). The Madurai and Trivandrum blocks have a clear component of Archean precursor based on Sm-Nd model ages ( Harris et al., 1994), but their dominantly Pan-African history precludes them from further consideration here. The boundary zones, at amphibolite facies with intense ductile shearing and flattening, include the Moyar-Bavali, ...
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... Eastern Ghats belt, ∼700 km long by 50-200 km wide and dissected by two MesoproterozoicPaleozoic rift zones (Rogers, 1986), is located along the eastern side of the Dharwar craton ( Figs. 1 and 7). Its southern and northern extents are not well delineated leading to multiple interpretations concerning its contact relation to major orogenic belts to the north and south (e.g., Radhakrishna and Naqvi, 1986;Mukhopadhyay, 1987;Radhakrishna, 1989). ...
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... ∼700 km and terminating near Delhi at its northern end, the Aravalli-Delhi orogenic belt exhibits a sweeping NE-SW trend through Rajasthan in northwest India (Figs. 1 and 7). The Rakhabdev lineament forms its western boundary, and the eastern boundary is marked by the Great Boundary fault that juxtaposes Mesoproterozoic sedimentary rocks of the Vindhyan basin with older rocks. ...
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... 3.3-2.5 Ga Bundelkhand granite massif ( Mondal et al., 2002), covering 26,000 km 2 , is a prominent feature east of the Aravalli-Delhi orogenic belt (Figs. 1 and 7). Initially described as monotonous granitic terrain dominated by unfoliated massive pink granite, this massif preserves an important multiepisode collision-cratonization granitoid history (Sharma, 1998;Sinha et al., 1998). ...
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... has led to tectonic reconstructions placing the Albany mobile belt as an extension of the CITZ at 1.6 Ga (Harris, 1993) or the westward continuation of the CITZ into the Trans-North China orogen at 1.8 Ga based on four possible juxtapositions of the Eastern block of North China with the south Indian craton ( Zhao et al., 2002Zhao et al., , 2003, Fig. 13). Mishra et al. (2000) and Mondal et al. (2002) proposed local relationships and links, but do not discuss the possible interconnectivity of various segments of India's orogenic belts. We propose a connection between various fragments of orogenic belts using the first Re-Os results and robust U-Pb geochronology along the southern margin ...
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... is a complex mosaic of sutured terranes that includes Archean and Proterozoic rocks of low- to high-grade metamorphism. Three early Archean cores, the Karnataka, Bastar, and Singhbhum, have been recognized in peninsular India ( Fig. 1), and their sedimentary-magmatic rocks have a geologic his- tory extending back to 3.6-3.5 Ga. Archean and Pro- terozoic rocks surround these cores, and continen- tal scale orogenic belts ( Fig. 1) contain enclaves and lithotectonic structures that preserve poorly defined episodes of ductile-brittle deformation. Among the less ...
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... rocks of low- to high-grade metamorphism. Three early Archean cores, the Karnataka, Bastar, and Singhbhum, have been recognized in peninsular India ( Fig. 1), and their sedimentary-magmatic rocks have a geologic his- tory extending back to 3.6-3.5 Ga. Archean and Pro- terozoic rocks surround these cores, and continen- tal scale orogenic belts ( Fig. 1) contain enclaves and lithotectonic structures that preserve poorly defined episodes of ductile-brittle deformation. Among the less well-studied belts is the Central Indian Tectonic Zone (CITZ; Acharyya, 2001), which connects penin- sular India to the mainland and overprints the Malan- jkhand batholith containing the giant Malanjkhand ...
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... enclaves and lithotectonic structures that preserve poorly defined episodes of ductile-brittle deformation. Among the less well-studied belts is the Central Indian Tectonic Zone (CITZ; Acharyya, 2001), which connects penin- sular India to the mainland and overprints the Malan- jkhand batholith containing the giant Malanjkhand Cu-Mo-Au deposit (Fig. 1). Near complete lack of robust geochronology hampers both correlations be- tween units within the CITZ and understanding of pro- cesses that brought these terranes together. Interpreta- tions for timing range from multi-phase development of the CITZ from 2.5 to 1.0 Ga ( Roy et al., 2001) to a younger Mesoproterozoic 1.0 Ga history ...
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... lies along the southern margin of the Central Indian Shear Zone (CIS; Jain et al., 1991), a brittle-ductile shear zone that forms the mylonitic southern boundary of the Cen- tral Indian Tectonic Zone (CITZ; Radhakrishna, 1989;Acharyya and Roy, 2000;Acharyya, 2001Acharyya, , 2003. Al- though the CIS is recognized as an old and stable su- ture ( Fig. 1), as also is the Sausar mobile belt (SMB), present-day reactivation of faults along the northern CITZ (Son-Narmada subzone, SONA) render the re- gion seismically active (Shanker, 1991). There is al- most no geochronology for the CITZ, which can be traced for 1600 km and attains widths of 200 km. The CITZ is covered to the west by the ...
Context 24
... also is the Sausar mobile belt (SMB), present-day reactivation of faults along the northern CITZ (Son-Narmada subzone, SONA) render the re- gion seismically active (Shanker, 1991). There is al- most no geochronology for the CITZ, which can be traced for 1600 km and attains widths of 200 km. The CITZ is covered to the west by the Deccan basalts ( Fig. 1), but nevertheless, it has been recognized as an important continental-scale tectonic zone of Protero- zoic age and a locality for important sutures (Yedekar et al., 1990;Jain et al., 1991;Mishra et al., 2000). The CITZ contains the not yet unraveled record of a colli- sion that brought together two cratons, the northern In- dian ...
Context 25
... et al., 1991;Mishra et al., 2000). The CITZ contains the not yet unraveled record of a colli- sion that brought together two cratons, the northern In- dian craton or Bundelkhand protocontinent to the north and the southern Indian craton or Dharwar protocon- tinent to the south. The latter includes the Dharwar, Bastar, and Singhbhum cratons ( Fig. 1). Others have used the term "Central Indian Shield" to refer to a pro- tocontinent comprised of the Bastar and Bundelkhand cratons with an intervening and periodically reactivated tectonic block (CITZ) designated as a major mobile belt (Divakara ...
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... Cen- tral Indian Tectonic Zone (CITZ); (2) the Sakoli fold belt (SK) to the southwest which forms a triangular wedge of supracrustal rocks that disappears beneath Deccan basalt cover; and (3) the Kotri-Dongargarh belt (KD) to the south, which hosts the Nandgaon volcanics and the intrusive Dongargarh granitoids in the northwestern Bastar craton (Fig. 1). Contacts be- tween these belts constitute major structural disconti- nuities about which relatively little is known. Even the most recent publications provide little agreement on regional geologic relationships and correlations (e.g., compare Acharyya and Roy, 2000, Fig. 2; Bhargava and Pal, 2000, Fig. 1; Bhowmik and Roy, 2003, Fig. ...
Context 27
... in the northwestern Bastar craton (Fig. 1). Contacts be- tween these belts constitute major structural disconti- nuities about which relatively little is known. Even the most recent publications provide little agreement on regional geologic relationships and correlations (e.g., compare Acharyya and Roy, 2000, Fig. 2; Bhargava and Pal, 2000, Fig. 1; Bhowmik and Roy, 2003, Fig. 2; Divakara Rao et al., 2000, Fig. 1; Mishra et al., 2000, Fig. 7;Ramachandra and Roy, 2001, Figs. 1 and 2;Roy et al., 2002, Fig. 1; Sikka and Nehru, 1997, Fig. 12), in itself rendering the context of Malanjk- hand controversial. Detailed mapping of key localities and boundaries is essential to ...
Context 28
... these belts constitute major structural disconti- nuities about which relatively little is known. Even the most recent publications provide little agreement on regional geologic relationships and correlations (e.g., compare Acharyya and Roy, 2000, Fig. 2; Bhargava and Pal, 2000, Fig. 1; Bhowmik and Roy, 2003, Fig. 2; Divakara Rao et al., 2000, Fig. 1; Mishra et al., 2000, Fig. 7;Ramachandra and Roy, 2001, Figs. 1 and 2;Roy et al., 2002, Fig. 1; Sikka and Nehru, 1997, Fig. 12), in itself rendering the context of Malanjk- hand controversial. Detailed mapping of key localities and boundaries is essential to understanding the rela- tionships between these three terranes and to placing ...
Context 29
... Even the most recent publications provide little agreement on regional geologic relationships and correlations (e.g., compare Acharyya and Roy, 2000, Fig. 2; Bhargava and Pal, 2000, Fig. 1; Bhowmik and Roy, 2003, Fig. 2; Divakara Rao et al., 2000, Fig. 1; Mishra et al., 2000, Fig. 7;Ramachandra and Roy, 2001, Figs. 1 and 2;Roy et al., 2002, Fig. 1; Sikka and Nehru, 1997, Fig. 12), in itself rendering the context of Malanjk- hand controversial. Detailed mapping of key localities and boundaries is essential to understanding the rela- tionships between these three terranes and to placing Malanjkhand in a modern tectonic context relative to ...
Context 30
... provide little agreement on regional geologic relationships and correlations (e.g., compare Acharyya and Roy, 2000, Fig. 2; Bhargava and Pal, 2000, Fig. 1; Bhowmik and Roy, 2003, Fig. 2; Divakara Rao et al., 2000, Fig. 1; Mishra et al., 2000, Fig. 7;Ramachandra and Roy, 2001, Figs. 1 and 2;Roy et al., 2002, Fig. 1; Sikka and Nehru, 1997, Fig. 12), in itself rendering the context of Malanjk- hand controversial. Detailed mapping of key localities and boundaries is essential to understanding the rela- tionships between these three terranes and to placing Malanjkhand in a modern tectonic context relative to ...
Context 31
... Sakoli fold belt (SK in Fig. 1) is in tec- tonic contact with the Amgaon gneiss complex to the north, east, and south. In this region the Am- gaon basement consists of high-grade supracrustal gneisses and migmatites, with Cr-bearing metaultra- mafics and pre-Sakoli supracrustal assemblages of quartzite, kyanite and sillimanite schists, calc-silicate rocks and ...
Context 32
... rocks of the Kotri-Dongargarh belt (KD in Fig. 1) lie unconformably on the Amgaon gneiss complex, which is composed of augen gneiss, banded gneiss and migmatites, and amphibolites in the Dongargarh-Malanjkhand region. The supracrustal rocks are dominated by greenschist facies Nandgaon volcanic sequences. Presently accepted belief is that this belt includes both the Malanjkhand and ...
Context 33
... and a conjugate set of structures with an ENE trend. A few of the scattered Cu-Mo-Au prospects in the batholith are hosted in local mylonites and shear zones that have been subsequently segmented by ENE faults with the northern segments successively rotated to the northwest, and some mineral occurrences have an ENE strike (Bhargava and Pal, 2000, Fig. 1). This ar- ray of structural features could be attributed to oblique convergence, a tectonic setting favoring formation of large Cu-Au deposits (e.g., Mungall, 2002). The struc- turally diverse Cu-Mo-Au prospects and the deforma- Fig. 7. Compilation of ∼2.5 Ga ages (largely U-Pb) in peninsular India and mainland India immediately north ...
Context 34
... boundary between the Archean Dharwar cra- ton and the largely Proterozoic Madurai and Trivan- drum blocks to the south is comprised of a complicated array of shear zones ( Radhakrishna et al., 2003) and the intervening high-grade Nilgari and Madras crustal provinces (Fig. 1). The Madurai and Trivandrum blocks have a clear component of Archean precursor based on Sm-Nd model ages ( Harris et al., 1994), but their dom- inantly Pan-African history precludes them from fur- ther consideration here. The boundary zones, at amphi- bolite facies with intense ductile shearing and flatten- ing, include the ...
Context 35
... Eastern Ghats belt, ∼700 km long by 50- 200 km wide and dissected by two Mesoproterozoic- Paleozoic rift zones (Rogers, 1986), is located along the eastern side of the Dharwar craton ( Figs. 1 and 7). Its southern and northern extents are not well de- lineated leading to multiple interpretations concern- ing its contact relation to major orogenic belts to the north and south (e.g., Radhakrishna and Naqvi, 1986;Mukhopadhyay, 1987;Radhakrishna, 1989). ...
Context 36
... ∼700 km and terminating near Delhi at its northern end, the Aravalli-Delhi orogenic belt ex- hibits a sweeping NE-SW trend through Rajasthan in northwest India (Figs. 1 and 7). The Rakhabdev lin- eament forms its western boundary, and the eastern boundary is marked by the Great Boundary fault that juxtaposes Mesoproterozoic sedimentary rocks of the Vindhyan basin with older rocks. ...
Context 37
... 3.3-2.5 Ga Bundelkhand granite massif ( Mondal et al., 2002), covering 26,000 km 2 , is a prominent feature east of the Aravalli-Delhi orogenic belt (Figs. 1 and 7). Initially described as monotonous granitic terrain dominated by unfoliated massive pink granite, this massif preserves an important multi- episode collision-cratonization granitoid history (Sharma, 1998;Sinha et al., 1998). ...
Context 38
... led to tectonic reconstructions placing the Albany mo- bile belt as an extension of the CITZ at 1.6 Ga (Harris, 1993) or the westward continuation of the CITZ into the Trans-North China orogen at 1.8 Ga based on four possible juxtapositions of the Eastern block of North China with the south Indian craton ( Zhao et al., 2002Zhao et al., , 2003, Fig. 13). Mishra et al. (2000) and Mondal et al. (2002) proposed local relationships and links, but do not discuss the possible interconnectivity of var- ious segments of India's orogenic belts. We propose a connection between various fragments of orogenic belts using the first Re-Os results and robust U-Pb geochronology along the southern ...
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Citations
... The present study addresses the nature of the crustal evolution of the Proterozoic basement rocks of the Tirodi Gneissic Complex (TGC) within the Central Indian Tectonic Zone (CITZ). This prominent suture zone has been brought out through the amalgamation of Northern and Southern Indian cratonic blocks, trending east-west for ~ 1600 km (Naqvi and Rogers 1987;Rogers and Gird 1997;Stein et al. 2004;Bhowmik et al. 2012) ; Fig. 1). The CITZ has preserved key information on Proterozoic geological evolution and records numerous significant events, including multistage tectonothermal events and magmatism during the Precambrian period. ...
... Moreover, the CITZ is polymetamorphic terrain, which belongs to the age brackets of 2.5 Ga and 1.6 Ga to 1.0 Ga (Meert et al. 2018). The young age, from 1.6 to 1.0 Ga, reflects the re-working of material within the older sequences (2.5 Ga; Stein et al. 2004). There are two pivotal ages, i.e., 1.7-1.8 ...
... The E-W trending CITZ has come into being through the amalgamation of NIB (North Indian Block: comprising of the Bundelkhand and Aravalli cratons) and SIB (South Indian Block: comprising of Bastar, Dharwar, and Singhbhum cratons) at 1.8 Ga, corresponding to the development of the Indian Subcontinent (Yedekar et al. 1990;Jain et al. 1991;Rogers and Gird 1997;Roy and Devarajan 2000;Stein et al. 2004;Bhowmik et al. 2012;Fig. 1A inset). ...
The Tirodi Gneissic Complex (TGC) represents the basement sequence of the Central Indian Tectonic Zone (CITZ), underlying the Proterozoic supracrustal sequences of the Sausar and Betul Groups of rocks. Lithologically, the TGC constitutes a combination of pink and grey granitic gneiss assemblages, characterised by biotite-rich, hornblende-biotite-rich, and muscovite-biotite-rich granite gneiss. Compositionally, the TGC granitoids represent tonalite-trondhjemite-granodiorite to granite, and have calc-alkaline lineage with metaluminous to peraluminous characteristics. Geochemically, they dominantly belong to A2-type granitoids. Chondrite normalised REE ratios of La/Sm, La/Yb, La/Gd, and Gd/Yb indicate diverse LREE/HREE enrichment. Multi-element patterns for the TGC granitoids are characterised by light rare earth elements (LREE) and large ion lithophile elements (LILE) enrichment and depletion of high field strength elements (HFSE: Nb, P, and Ti) and strong positive Pb and Th anomalies. The observed negative anomalies for HFSE are attributed to diverse crustal/lithospheric sources, with some influence from K-feldspar, plagioclase and Ti-oxide fractionation. Sm–Nd data presents initial ¹⁴³Nd/¹⁴⁴Nd (t = 1.7 Ga) ratios (0.509898 to 0.510508), and εNd (t = 1.7 Ga) is (+ 0.58 to -10.59), with TDM model ages ranging from 2.11 to 2.95 Ga. Such a wide range of εNd (t = 1.7 Ga), indicates heterogeneous crustal/lithosphere sources, which have probably experienced longer crustal residence times. Zircon U–Pb ages for individual TGC samples are 1506 ± 11 Ma (TG-01), 1534 ± 26 Ma (MU-5), 1675 ± 9 Ma (BT-4), 1724 ± 11 Ma (BT-3), 1730 ± 13 Ma (BT-4), and 1960 ± 2 Ga (Ms-2), respectively. These ages have probably recorded the key periods of the Columbia supercontinent's assembly, growth, and breakup. Geochemical and geochronological results suggest that the TGC granitoids have a crustal/lithospheric origin and are formed by partial melting of felsic sources in dominantly VAG (volcanic arc granite) and, to some extents, WPG (within-plate granite) settings.
... 6). Consequently, sulfide Re-Os geochronology has been used to successfully date a wide assortment of ore types including orogenic gold, porphyry, Mississippi Valley-type and volcanogenic massive sulfide deposits, and other types of sediment-hosted ores, resulting in dozens of publications in the past 20 years, with precision routinely approaching <1% (e.g., Stein et al., 2000Stein et al., , 2004Hannah and Stein, 2002;Brooks et al., 2004;Morelli et al., 2004Morelli et al., , 2007Wilson et al., 2007;Zimmerman et al., 2008Zimmerman et al., , 2014Bjerkgard et al., 2009;Lawley and Selby, 2012;Lawley et al., 2013Lawley et al., , 2015Hnatyshin et al., 2015Hnatyshin et al., , 2016Zhang et al., 2016;Saintilan et al., 2017aSaintilan et al., , 2017bSaintilan et al., , 2018Saintilan et al., , 2020aSaintilan et al., , 2021Cawood et al., 2022;Tassara et al., 2022). Many sulfide minerals have been shown to retain robust Re-Os age information through post-mineralization thermal disturbances (Morelli et al., 2010;van Acken et al., 2014;Vernon et al., 2014;Saintilan et al., 2017bSaintilan et al., , 2018Saintilan et al., , 2023a Fig. 7). ...
... Establishing the timing and source of fluid flow in ore deposits (e.g., the interaction of mineralizing brines and metal-rich basement rocks or melts from metal-rich mantle domains) is critical for developing genetic models of ore for-mation. The Osi ratios derived from sulfide mineral isochrons of Archean to Phanerozoic age can range from between ∼0.12 to >>10 (e.g., Brooks et al., 2004;Morelli et al., 2004Morelli et al., , 2007Stein et al., 2004;Wilson et al., 2007;Hnatyshin et al., 2015;Saintilan et al., 2017aSaintilan et al., , 2017bSaintilan et al., , 2018. These Osi ratios can, to a first-order, be used to distinguish between a mantle-related or a crustderived source of the Os and associated metals (e.g., Sillitoe et al., 2015Sillitoe et al., , 2017Saintilan et al., 2018;Tassara et al., 2022). ...
The rhenium-osmium (187Re-187Os) system is a highly versatile chronometer that is regularly applied to a wide range of geological and extraterrestrial materials. In addition to providing geo- or cosmo-chronological information, the Re-Os system can also be used as a tracer of processes across a range of temporal (millennial to gigayear) and spatial scales (lower mantle to cryosphere). An increasing number of sulfide minerals are now routinely dated, which further expands the ability of this system to refine mineral exploration models as society moves toward a new, green economy with related technological needs. An expanding range of natural materials amenable to Re-Os geochronology brings additional complexities in data interpretation and the resultant translation of measured isotopic ratios to a properly contextualized age. Herein, we provide an overview of the 187Re-187Os system as applied to sedimentary rocks, sulfides, and other crustal materials and highlight further innovations on the horizon. Additionally, we outline next steps and best practices required to improve the precision of the chronometer and establish community-wide data reduction procedures, such as the decay constant, regression technique, and software packages to use. These best practices will expand the utility and viability of published results and essential metadata to ensure that such data conform to evolving standards of being findable, accessible, interoperable, and reusable (FAIR).
... 2490 Ma and ca. 2475-2450 Ma; Stein et al., 2004), the Chapada Cu-Au deposit in central Brazil (ca. 867-884 Ma for porphyry-type and ca. ...
... The Vestfold Hills have also been identified as being distinct from the other Archean exposures of Princess Elizabeth Land i.e., from the Ruker terrane (e.g., Snape et al., 1997) and from the Rauer Group (e. g., Harley et al., 1995) as it is largely devoid of Neoproterozoic reworking and Pan-African overprinting (Harley, 2003). In the context of supercontinent connections, the Vestfold Hills are proposed to resemble Indian cratons (Fitzsimons, 2003;Stein et al., 2004;Boger, 2011) and are suggested to have been juxtaposed with the eastern and north-eastern Indian shield during the final amalgamation of Gondwana (Collins and Pisarevsky, 2005). Clark et al. (2012) proposed connections between the Vestfold Hills and the North China craton based on detrital zircon ages from the former and zircon crystallization ages from the latter. ...
... Ga) along the NE -SW-trending CITZ (Fig. 1a). The CITZ is over 1600 km long and 200 km wide (Stein et al. 2004), bounded by two lineaments, namely: the Son-Narmada South Fault (SNSF) in the north; and the CIS in the south (Fig. 1a). The CIS is a brittle-ductile shear zone formed because of a collision (Yedekar et al. 1990;Jain et al. 1991;Roy & Devarajan 2000;Acharyya 2001Acharyya , 2003 between the Bundelkhand and the Bastar cratons (Leelandandam et al. 2006). ...
... Contemporaneous subduction-related events and granitic magmatism are also been proposed in the Malanjkhand area and the timing of which is estimated to be at 2490 ± 8 Ma (Stein et al., 2004). Panigrahi et al. (2004) estimated 2.48 Ga for the granites from the Malanjkhand area. ...
... Panigrahi et al. (2004) estimated 2.48 Ga for the granites from the Malanjkhand area. Further reworking events associated with the granitic magmatism and porphyry mineralization at Malanjkhand area have been noticed at ~2475 and ~2450 Ma (Stein et al., 2004). Contemporaneous granitic emplacements can also be noticed in Kanker areas, which further substantiates the Siderian Period was significant in terms of crustal evolution in the Bastar craton (Pandit and Panigrahi, 2012;Asokan et al., 2020). ...
Several layered igneous complexes around the globe host ultramafic-mafic lithologies at the base to more evolved
lithologies at the roof sections. In this study, we report U-Pb zircon ages and geochemistry of Paleoproterozoic
granites and Khallari layered intrusion from the Dongargarh Supergroup of Bastar craton, central India. The
Khallari layered intrusion hosts pyroxenites at the base to more evolved lithologies including gabbro, layered
gabbro and anorthositic gabbros towards the roof section of the magma chamber. The estimated weighted mean
U-Pb zircon ages of granites (2443 ± 13 Ma) and layered intrusion (2494 ± 19 Ma and 2469.2 ± 5.2 Ma) are in
conjunction with the major Siderian crust building peak identified at the craton. The granitic plutons of the
Dongargarh Supergroup are chemically similar to post-collisional/anorogenic granitic rocks, in which the
rapakivi granites exhibit a fractional crystallization relation with the Khallari layered intrusion. The Dongargarh
granites and enclaves were derived by a combination of fractional crystallization and mixing of partial melts
from the pre-existing crust of the Bastar craton. Petrogenetic modeling indicates Khallari layered intrusion is
formed by the fractional crystallization of lithospheric mantle melt followed by crystal accumulation. The
parental melt also experienced localized crustal contamination (up to 10%) during its evolution. The layered
intrusion and the granites formed in a post-collisional rift setting where magmatism postdates the proposed
subduction and collisional orogenesis at 2.5 Ga involves cratonic domains of Eastern and Western Bastar cratons.
... The cratonization of the Bastar Craton is marked by the emplacement of a number of granitic bodies. Out of them, the Malanjkhand, Dongargarh, Kanker and Manpur granites (Ramachandra, 1994;Stein et al., 2004;Asokan et al., 2020) are the four important granitic bodies. Though, the batholith related to the Dongargarh magmatic event. ...
Heterogeneous nature, textural variation, and compositional diversity are reported from the north-western part of the Kanker Granites, exposed in parts of Kanker District, Chhattisgarh, India, where the possible petrogenesis and tectonic history of the same, with special emphasis on its REE mineralogy and genesis. The granites are ferroan, alkalic to sub-alkalic, per-aluminous and oxidized A-type in nature. An integrated field-petrography-whole rock analysis-mineral chemistry approach indicates injection of mafic magma into crystallizing felsic host with different stages of interaction through mixing, mingling and hybridization. Major oxides, trace elements and REE geochemistry suggest derivation from a predominant crustal source involving a variable degree of mantle input, with a key role of fractional crystallization from mafic magma and partial melting of quartzo-feldspathic igneous sources during petrogenesis. The evolution of the granites can be best explained in an accretionary post-orogenic (collision) phase in subduction setting (A2-type granites) during the Archean-Proterozoic transition. The granites are enriched in LREE, the REE bearing phases being monazite, xenotime, allanite, parisite, and zircon. Occurrence of the REEs in granites probably have occurred through magmatic processes, hydrothermal fluid mobilization and precipitation. The REE contents in granites can be a potential resource in terms of economic geology.
... There exists debate within the literature regarding the advent of subduction and specifically its occurrence in the Precambrian (Wyman et al. 2002, Bédard et al. 2013. Porphyry deposits in the Precambrian have been used to infer the presence of subduction (e.g., Malanjkhand, India; Stein et al. 2004). A comparison of the TSM from a Precambrian porphyry-like system may shed light on the link between Precambrian and more recent ''typical'' porphyry systems. ...
Samples of tourmaline supergroup minerals from seven mineralized porphyry systems (Cu, ±Au, ±Mo), including Casino (Yukon Territory, Canada), Coxheath (Nova Scotia, Canada), Donoso breccia-Los Bronces (Chile), Highland Valley Copper (British Columbia, Canada), New Afton (British Columbia, Canada), Schaft Creek (British Columbia, Canada), and Woodjam (British Columbia, Canada), were examined at a variety of scales to evaluate their relationships with mineralization. Data from paragenetic observations show that tourmaline supergroup minerals are generally early hydrothermal minerals that predate both mineralization and alteration (e.g., overgrown and crosscut by). In general, tourmaline supergroup minerals occur as sub- to euhedral crystals that are black in hand sample and can be found in a variety of mineralized settings (including breccias, veins, and disseminations) and alteration assemblages (including potassic, sodic-calcic, phyllic, propylitic, and argillic). As tourmaline supergroup minerals are physically and chemically resilient and occur throughout a given porphyry system, they are comprehensive recorders of the type and extent of various geochemical processes that exist during the complex genesis of these systems. Data from BSE imaging shows two primary zonation types: concentric and sector. These are interpreted to reflect conditions of rapid crystallization and disequilibrium. Results from SEM-EDS analyses show that most tourmaline supergroup minerals are dravite (∼80% of grains), with the remainder being primarily classified as schorl. Porphyry tourmaline supergroup minerals exhibit remarkably consistent ∼2.0 apfu Mg values (range: 0.69–2.89), with the majority of tourmaline supergroup minerals plotting along the oxy-dravite–povondraite trend, reflecting the predominance of the Al3+ ↔ Fe3+ substitution at constant Mg values. This pattern starts from the povondraite side (reflecting the oxidizing nature of early porphyry mineralizing fluids) and trends toward oxy-dravite as a porphyry system evolves, a feature that can, in turn, be interpreted to reflect relative emplacement depths. In mineralized porphyry systems, tourmaline supergroup minerals exhibit remarkably similar physical and chemical characteristics among the systems examined, suggesting that the source and geological processes must be extraordinarily similar. Unfortunately, these characteristics are not unique to porphyry systems and such observations should be integrated with additional data, such as trace element mineral chemistry, to effectively discriminate tourmaline supergroup minerals that have formed in porphyry systems.
... The SGB is located on the northeastern fringes of Bastar Craton and is almost perpendicular to the NE-SW trending Central Indian Tectonic Zone ( Fig. 1B) (Manu Prasanth et al. 2017). These supracrustals are intruded by Mesoarchean gneisses (also known as Bengpal/Baya/ Sukma gneisses of 3081 ± 60 Ma age, Sarkar et al. 1993) and numerous Proterozoic granites (i.e., Dongargarh granite, Bundeli Granitoid and Malanjkhand of * 2500 Ma ages, Sarkar et al. 1993;Stein et al. 2004), which was followed by intrusive mafic magmatic dike swarms (1891-1883Ma, French et al. 2008). These gneisses/granites also contain the xenoliths of supracrustals, i.e., Sukma and Bengpal Group of rocks, which vary in size from a few meters to kilometres and are inhomogeneously distributed in the area (Fig. 1B). ...
The present study reports and discusses the genesis of zincian chromite in the ultramafic xenoliths from the Dongripali area, Bastar craton, Central India. The zincian chromite is in the ultramafic xenoliths of Bengpal supracrustal rock hosted by Neoarchaean Bundeli gneisses. Compositionally zincian chromite shows a range of Cr2O3 (39.69 to 51.66 wt%), Al2O3 (05.30 wt% to 08.71 wt%), FeO (21.74 wt% to 27.51 wt%), Fe2O3 (10.19 wt% to 19.36 wt%) with higher ZnO content ranging from 1.73 wt% to 4.08 wt%. Accordingly, their Cr# [Cr/(Cr + Al)] varies in a narrow range from 0.83 to 0.85. Its calculated melt composition supports metamorphic or post-magmatic nature rather than common occurrences such as inclusion in diamonds, meteorites, and association with any sulfide-rich mineralised belt. This reveals that the post-magmatic processes play a vital role in transforming chromite to zincian chromite. The empirical thermometric calculation from chromite, amphibole, and pyroxene support their metamorphic origin and formed during low-P and high-T amphibolite grade facies of metamorphism (~ 700 °C). The Neoarchaean granitic magmatism has a significant role in generating and transferring the heat during contact metamorphism with hydration of ultramafic xenoliths and further alteration, i.e., serpentinisation. The olivine is a major repository for Mn, Zn, and Co in peridotite/ultramafic; these elements get mobilised during the metamorphism and serpentinisation. This is a possible reason for the mobilisation of zinc and incorporation in the chromite within altered ultramafic. As a result, chromite-rich ultramafic xenolith subjected to metamorphic process gets enrichment of Zn and Fe due to elemental exchange. It converts common chromite into zincian chromite, as reported in altered ultramafics elsewhere.
... The majority of the world's copper ore comes from porphyry type copper deposits (Sinclair 2007;Sillitoe 2010;Sun et al. 2017) followed by sediment hosted (Hitzman et al. 2005Borg et al. 2012;Sillitoe et al. 2017) and IOCG type of deposits (Hitzman 2000;Sillitoe 2003;Skirrow et. al. 2007;Groves et al. 2010;Sillitoe 2012 In India, copper deposits occur in three major belts namely (1) hydrothermal type Singhbhum Copper Belt in Jharkhand comprise the Surda, Raka, and Mosaboni areas (Mishra et al. 2003;Pal et al. 2009Pal et al. , 2010Chowdhury et al. 2020;Patel et al. 2021), (2) porphyry type Malanjkhand Copper deposit in Madhya Pradesh (Bhargava and Pal 2000;Stein et al. 2004;Panigrahi et al. 2009;Asthana et al. 2015), and (3) IOCG type Khetri Copper Belt in Rajasthan (Knight et al. 2002;Chen et al. 2015;Baidya et al. 2017;Li et al. 2018;Baidya and Pal 2020). These copper deposits comprise primary sulfides dominated by chalcopyrite. ...
Nim Ka Thana Copper Belt, in Rajasthan, India is well-known for the bornite dominated copper deposits. The present study area covers three prospects, i.e., Nanagwas, Dariba North, and Toda-Ramliyas, located in the central to the southern part of the belt. The sulfide mineralization is hosted within the carbonaceous phyllite and banded impure marble of the Paleoproterozoic sequence of the Delhi Supergroup but copper mineralization is only hosted within the banded impure marble. In this study, we use mineral chemistry of sulfide minerals, fluid inclusion of quartz vein, and sulfur isotopic geochemistry to decipher the genesis of sulfide mineralization. Nim Ka Thana copper belt exhibits a wide range of Ca-Na–K-B metasomatism. Mineral chemistry of pyrite and pyrrhotite shows Co/Ni ratio varies between 0.20–20 and 0.19–15 respectively. Three types of fluid inclusions are observed within mineralized quartz veins and homogenized within the temperature range of 121.5 °C to 390.1 °C and salinities of 0.33 wt% to 16.80 wt% NaCl equivalents. The homogenization temperature and salinity indicates the isothermal mixing and simple cooling of the ore-forming fluids and they are of metamorphic origin. Sulfur isotopic composition of major sulfides shows a bimodal distribution of δ34SVCDT (‰) values ranging from − 37.85‰ to + 6.33‰. It indicates that the ore-forming metals and sulfur come from a mixed source that encompasses sedimentary and hydrothermal sources. Based on field observation, ore mineral chemistry, petrographic study, fluid inclusion, and sulfur isotope study, it is inferred that the sulfide mineralization is overprinting of sedimentary and hydrothermal origin but copper mineralization is formed by the hydrothermal process.
