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A comment on “Correlations between the Eastern Block of the North China Craton and the Southern Indian block of the Indian Shield: an Archaean to palaeoproterozoic link”—Reply
Precambrian Research 127 (2003) 381–383
Comment
A comment on “Correlations between the Eastern Block of the North China Craton and the Southern Indian block of the Indian Shield: an Archaean to palaeoproterozoic link”—Reply Guochun Zhao a,∗ , Min Sun a , Simon A. Wilde b b
a Department of Earth Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China Department of Applied Geology, Curtin University of Technology, GPO Box U1987, Perth, WA 6845, Australia
Accepted 7 June 2003
We would like to thank Rajat Mazumder for his discussion concerning our article “Correlations between the Eastern Block of the North China Craton and the Southern Indian Block of the Indian Shield: an Archaean to Palaeoproterozoic link” (Zhao et al., 2003). We are pleased to note that Mazumder does not raise questions concerning our prime conclusions that the Eastern Block (North China) and the Southern Indian Block share remarkable similarities in Archaean and Palaeoproterozoic magmatic, sedimentary and tectonometamorphic features, and that it is possible that the two blocks are dispersed remnants of what was once a single continent from Archaean to Palaeoproterozoic. However, he highlights two interesting but controversial questions; one concerning the nature of Palaeoproterozoic stratigraphic sequences in the Southern Indian Block, and the other concerning correlations of palaeogeographic settings, sea level changes and their temporal variations between Palaeoproterozoic volcano-sedimentary successions in the two blocks. In his first argument, Mazumder questions the validity of Palaeoproterozoic stratigraphic sequences of the Singhbhum Craton we adopted in our paper, ∗ Corresponding author. Tel.: +852-28578203; fax: +852-25176912. E-mail address: [email protected] (G. Zhao).
namely that the Dhanjori Group is placed on the top of the Singhbhum Group. He claims that an early stratigraphic subdivision (Dunn and Dey, 1942; Sarkar and Saha, 1962) in which the Dhanjori Group was interpreted to be younger than the Singhbhum Group, has been criticized by subsequent workers (Sarkar and Deb, 1971; Mukhopadhaya, 1976). He also claims that field observations show that the Dhanjori-Chaibasa (the lower formation of the Singhbhum Group) succession preserves a normal stratigraphic order, and thus the Dhanjori Group lying at the bottom should be older than the Singhbhum Group (e.g. Mukhopadhaya, 1976; Bose and Chakraborty, 1981; Mazumder et al., 2000; Mazumder, 2002). In addition, based on a new Sm–Nd whole-rock isochron age of ∼2.1 Ga from the Dhanjori Group (Roy et al., 2002a) and a Rb–Sr age of ∼1.6 Ga from the Dalma volcanics (Roy et al., 2002b) that conformably overlies the upper part of the Singhbhum Group, Mazumder suggests that the Dhanjori Group formed about 2.1 Ga ago and the Singhbhum Group developed at some time between 2.1 and 1.6 Ga. We regret to find that Mazumder quoted some unreliable data and references, mostly published in local Indian literature, to make his arguments. Moreover, some references that Mazumder uses to defend his arguments had not come out at the time we submitted our paper (e.g. Mazumder, 2002; Roy et al., 2002a,b). In contrast, most references that we used in our paper
0301-9268/$ – see front matter © 2003 Elsevier B.V. All rights reserved. doi:10.1016/S0301-9268(03)00196-7
382
G. Zhao et al. / Precambrian Research 127 (2003) 381–383
(e.g. Naqvi and Rogers, 1987; Goodwin, 1991; Mishra et al., 1999, etc.) are widely accessible to the international community, and these references all consider the Dhanjori Group to be younger than the Singhbhum Group. For example, on page 338 of his classic book Precambrian Geology, Goodwin (1991) gave the following description about the Singhbhum, Dhanjori and Kolhan Groups: The Singhbhum Group includes the lower Chaibasa Formation (7000-7600 m) composed of a thin basal metaconglomerate overlain by moderately high grade micaschist, quartzite and amphibolite. North of the Copperbelt Thrust Zone the Chaibasa Formation is conformably overlain by the Dhalbhum Formation (2100-4000 m), composed of phyllitic schist and quartzite. These rocks are unconformably overlain by the Dhanjori Group, comprising a basal quartzite-conglomerate overlain by a thick sequence of mafic lavas intercalated with thick sandstones. Several essentially mafic lava-rich sequences are called Jagannathpur (west) and Dhanjori-Simlipal (east) to the south of the thrust, and Dalma or Malangtoli lavas to the north (Sarkar and Saha, 1962). In Simlipal Basin, 30 km south of the thrust, the Dhanjori Group is represented by a 10000 m thick sequence of slightly metamorphosed mafic lava flows containing three prominent quartzite-sandstone intercalations. Mafic lava intrusion in the western basins was followed by (and locally preceded by) the deposition of the Kolhan Group, representing an upward transgression from sandstone-conglomerate to shales and limestones. A similar description on the relationships of the Singhbhum, Dhanjori and Kolhan Groups was also given by Mishra et al. (1999) in their paper published in Precambrian Research (vol. 93, pp. 139–151): Subsequent events in the evolution of the Singhbhum Craton include the unconformable deposition of the Singhbhum Group supracrustals (Sarkar and Saha, 1962; Sarkar and Saha, 1983), followed by the formation of the Dhanjori Group volcanosedimentary sequence, followed by the deposition of the Kolhan Group clastics. Mishra et al. (1999) also presented a table showing the age ranges of the major lithologies including the Singhbhum, Dhanjori and Kolhan Groups in the
Table 1 Simplified chronostratigraphic succession for the Singhbhum Craton (Mishra et al., 1999) Lithologies
Age (Ga)
Kolhan Group Jagannathpur and Dhanjori lavas Singhbhum Group Unconformity Singhbhum Granite (phase III) Iron Ore Group Singhbhum Granite (phases I and II) Older Metamorphic Group and Older Metamorphic Tonalite Gneiss
2.2–2.1 2.4–2.3 c. 3.1 c. 3.3 3.5–3.4
Singhbhum Craton (Table 1). As shown in Table 1, Mishra et al. (1999) interpreted the Singhbhum and Kolhan Groups to have formed in the periods of 2400–2300 Ma and 2200–2100 Ma, respectively, whereas the Jagannathpur and Dhanjori lavas of the Dhanjori Group were restricted to the period of 2300–2200 Ma. The age ranges for the Singhbhum and Dhanjori Groups are similar to those that Goodwin (1991) assigned to the same groups in Table 2-26 of his book, but are different from the ages that Mazumder has proposed in his discussion, especially for the Singhbhum Group. Mazumder suggests that the Dhanjori Group formed at ∼2.1 Ga, based on a Sm–Nd whole-rock isochron age of 2072 ± 106 Ma obtained by Roy et al. (2002a) from the Dhanjori Group. However, this age is too imprecise to constrain the timing of the formation of the Dhanjori Group because of its large error. In addition, based on the ∼2.1 Ga Sm–Nd age and a 1619 ± 38 Ma Rb–Sr isochron age obtained Roy et al. (2002b) from the Dalma volcanics that conformably overlies the upper part of the Singhbhum Group, Mazuinder interprets the Singhbhum Group as having developed at some time between 2.1 and 1.6 Ga. This interpretation is established on the basis of his argument that the Dhanjori–Singhbhum succession preserves a normal stratigraphic order and thus that, the Dhanjori Group lying at the bottom should be older than the Singhbhum Group. However, according to Bhattacharya (1992), the Singhbhum and Dhanjori Groups underwent at least four phases of deformation, of which the earliest phase (F1 ) shows tight to isoclinal folds with strongly developed E–W striking axial-plane schistocity and variable axial plunges;
G. Zhao et al. / Precambrian Research 127 (2003) 381–383
the second phase of deformation (F2 ) was the most widespread and thoroughly refolded the F1 structures, and the third (F3 ) and fourth (F4 ) phases locally refolded the F1 and F2 structures. In a region of such complex structure, it would be difficult to confirm that the Singhbhum and Dhanjori Groups still preserve a normal stratigraphic order. The second argument Mazumder raises in his discussion is about correlations involving palaeogeographic settings, sea level changes and their temporal variations between Palaeoproterozoic volcano-sedimentary successions of the Eastern Block (North China) and the Southern Indian Block. Mazumder points out that our original correlations between the Liaohe Group in China and the adjoining Singhbhum, Dhanjori and Kolhan Groups in India are only limited to their gross lithological characteristics, but did not consider palaeogeographic environment, relative sea level change and their temporal variations and other parameters. On the basis of his first argument that the Dhanjori Group is older than the Singhbhum Group, Mazumder then presents a detailed analysis of palaeogeographic setting, sea level change and their temporal variations for the Singhbhum, Dhanjori and Kolhan Groups of the Singhbhum Craton. In response, we have no argument with Mazumder’s suggestion that a similar analysis for the Palaeoproterozoic Liaohe Group will provide a better insight in testing the Archaean to Palaeoproterozoic link of North China and India. However, we consider that lithological/stratigraphic characteristics are also relevant to the analysis of palaeogeographic setting, sea level change and their temporal variations. As shown in Fig. 11 of our original paper (Zhao et al., 2003), the volcano-sedimentary successions of the lower, middle and upper parts of the Liaohe Group are remarkably similar to those of the Singhbhum, Dhanjori and Kolhan Groups, respectively, and thus, the palaeogeographic setting, sea level change and their temporal variations reflected by the Liaohe Group may also be similar to those reflected by the adjoining Singhbhum, Dhanjori and Kolhan Groups. Therefore, we think that lithological/stratigraphic correlations are the first and most important parameters to consider when undertaking reconstruction of ancient continental blocks.
383
Acknowledgements This study was supported by Hong Kong RGC grants (HKU7115/00P and HKU7090/0l P). References Bhattacharya, D.S., 1992. Early Proterozoic metallogeny, tectonics and geochronology of the Singhbhum Cu–U Belt, Eastern India. Precambrian Res. 58, 71–83. Bose, M.K., Chakraborty, M.K., 1981. Fossil marginal basin from the Indian Shield: a model for the evolution of Singhbhum Precambrian belt, Eastern India. Geol. Rundsch. 70, 504–518. Dunn, J.A., Dey, A.K., 1942. The geology and petrology of Eastern Singhbhum and surrounding areas. Mem. Geol. Surv. India 69, 281–456. Goodwin, A.M., 1991. Precambrian Geology. Academic Press, Toronto, 666 pp. Mazumder, R., 2002. Sedimentation History of the Dhanjori and Chaibasa Formations, Eastern India and its Implications. Unpublished Ph.D. Thesis, Jadavpur University, 119 pp. Mazumder, R., Bose, P.K., Sarkar, S., 2000. A commentary on the tectono-sedimentary record of the pre-2.0 Ga continental growth of India vis a vis a pre-Gondwana Afro-Indian supercontinent. J. African Earth Sci. 30, 201–217. Mishra, S., Deomurari, M.P., Wiedenbeck, M., Goswami, J.N., Ray, S., Saha, A.K., 1999. 207Pb/206Pb zircon ages and the evolution of the Singhbhum Craton, Eastern India: an ion microprobe study. Precambrian Res. 93, 139–151. Mukhopadhaya, D., 1976. Precambrian stratigraphy of Singhbhum—the problems and prospectives. Indian J. Earth Sci. 3, 208–219. Naqvi, S.M., Rogers, J.J.W., 1987. Precambrian Geology of India. Oxford University Press, Oxford, 223 pp. Roy, A., Sarkar, A., Jeyakumar, S., Aggrawal, S.K., Ebihara, M., 2002a. Sm–Nd age and mantle source characteristics of the Dhanjori volcanic rocks, Eastern India. Geochem. J. 36, 503– 518. Roy, A., Sarkar, A., Jeyakumar, S., Aggrawal, S.K., Ebihara, M., 2002b. Mid-Proterozoic plume-related thermal event in Eastern Indian craton: evidence from trace elements, REE geochemistry and Sr–Nd isotope systematics of basic-ultrabasic intrusives from Dalma Volcanic Belt. Gondwana Res. 5, 133–146. Sarkar, S.C., Deb, M., 1971. Dhanjori basalts and some related rocks. Quart. J. Geol. Min. Met. Soc. India 43, 29–37. Sarkar, S.N., Saha, A.K., 1962. A revision of the Precambrian stratigraphy and tectonics of Singhbhum and adjacent regions. Quart. J. Geol. Min. Metal. Soc. India 34, 97–136. Zhao, G.C., Sun, M., Wilde, S.A., 2003. Correlations between the Eastern Block of the North China Craton and the South Indian Block of the Indian Shield: an Archaean to Palaeoproterozoic link. Precambrian Res. 122, 201–233.
Comment
A comment on “Correlations between the Eastern Block of the North China Craton and the Southern Indian block of the Indian Shield: an Archaean to palaeoproterozoic link”—Reply Guochun Zhao a,∗ , Min Sun a , Simon A. Wilde b b
a Department of Earth Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China Department of Applied Geology, Curtin University of Technology, GPO Box U1987, Perth, WA 6845, Australia
Accepted 7 June 2003
We would like to thank Rajat Mazumder for his discussion concerning our article “Correlations between the Eastern Block of the North China Craton and the Southern Indian Block of the Indian Shield: an Archaean to Palaeoproterozoic link” (Zhao et al., 2003). We are pleased to note that Mazumder does not raise questions concerning our prime conclusions that the Eastern Block (North China) and the Southern Indian Block share remarkable similarities in Archaean and Palaeoproterozoic magmatic, sedimentary and tectonometamorphic features, and that it is possible that the two blocks are dispersed remnants of what was once a single continent from Archaean to Palaeoproterozoic. However, he highlights two interesting but controversial questions; one concerning the nature of Palaeoproterozoic stratigraphic sequences in the Southern Indian Block, and the other concerning correlations of palaeogeographic settings, sea level changes and their temporal variations between Palaeoproterozoic volcano-sedimentary successions in the two blocks. In his first argument, Mazumder questions the validity of Palaeoproterozoic stratigraphic sequences of the Singhbhum Craton we adopted in our paper, ∗ Corresponding author. Tel.: +852-28578203; fax: +852-25176912. E-mail address: [email protected] (G. Zhao).
namely that the Dhanjori Group is placed on the top of the Singhbhum Group. He claims that an early stratigraphic subdivision (Dunn and Dey, 1942; Sarkar and Saha, 1962) in which the Dhanjori Group was interpreted to be younger than the Singhbhum Group, has been criticized by subsequent workers (Sarkar and Deb, 1971; Mukhopadhaya, 1976). He also claims that field observations show that the Dhanjori-Chaibasa (the lower formation of the Singhbhum Group) succession preserves a normal stratigraphic order, and thus the Dhanjori Group lying at the bottom should be older than the Singhbhum Group (e.g. Mukhopadhaya, 1976; Bose and Chakraborty, 1981; Mazumder et al., 2000; Mazumder, 2002). In addition, based on a new Sm–Nd whole-rock isochron age of ∼2.1 Ga from the Dhanjori Group (Roy et al., 2002a) and a Rb–Sr age of ∼1.6 Ga from the Dalma volcanics (Roy et al., 2002b) that conformably overlies the upper part of the Singhbhum Group, Mazumder suggests that the Dhanjori Group formed about 2.1 Ga ago and the Singhbhum Group developed at some time between 2.1 and 1.6 Ga. We regret to find that Mazumder quoted some unreliable data and references, mostly published in local Indian literature, to make his arguments. Moreover, some references that Mazumder uses to defend his arguments had not come out at the time we submitted our paper (e.g. Mazumder, 2002; Roy et al., 2002a,b). In contrast, most references that we used in our paper
0301-9268/$ – see front matter © 2003 Elsevier B.V. All rights reserved. doi:10.1016/S0301-9268(03)00196-7
382
G. Zhao et al. / Precambrian Research 127 (2003) 381–383
(e.g. Naqvi and Rogers, 1987; Goodwin, 1991; Mishra et al., 1999, etc.) are widely accessible to the international community, and these references all consider the Dhanjori Group to be younger than the Singhbhum Group. For example, on page 338 of his classic book Precambrian Geology, Goodwin (1991) gave the following description about the Singhbhum, Dhanjori and Kolhan Groups: The Singhbhum Group includes the lower Chaibasa Formation (7000-7600 m) composed of a thin basal metaconglomerate overlain by moderately high grade micaschist, quartzite and amphibolite. North of the Copperbelt Thrust Zone the Chaibasa Formation is conformably overlain by the Dhalbhum Formation (2100-4000 m), composed of phyllitic schist and quartzite. These rocks are unconformably overlain by the Dhanjori Group, comprising a basal quartzite-conglomerate overlain by a thick sequence of mafic lavas intercalated with thick sandstones. Several essentially mafic lava-rich sequences are called Jagannathpur (west) and Dhanjori-Simlipal (east) to the south of the thrust, and Dalma or Malangtoli lavas to the north (Sarkar and Saha, 1962). In Simlipal Basin, 30 km south of the thrust, the Dhanjori Group is represented by a 10000 m thick sequence of slightly metamorphosed mafic lava flows containing three prominent quartzite-sandstone intercalations. Mafic lava intrusion in the western basins was followed by (and locally preceded by) the deposition of the Kolhan Group, representing an upward transgression from sandstone-conglomerate to shales and limestones. A similar description on the relationships of the Singhbhum, Dhanjori and Kolhan Groups was also given by Mishra et al. (1999) in their paper published in Precambrian Research (vol. 93, pp. 139–151): Subsequent events in the evolution of the Singhbhum Craton include the unconformable deposition of the Singhbhum Group supracrustals (Sarkar and Saha, 1962; Sarkar and Saha, 1983), followed by the formation of the Dhanjori Group volcanosedimentary sequence, followed by the deposition of the Kolhan Group clastics. Mishra et al. (1999) also presented a table showing the age ranges of the major lithologies including the Singhbhum, Dhanjori and Kolhan Groups in the
Table 1 Simplified chronostratigraphic succession for the Singhbhum Craton (Mishra et al., 1999) Lithologies
Age (Ga)
Kolhan Group Jagannathpur and Dhanjori lavas Singhbhum Group Unconformity Singhbhum Granite (phase III) Iron Ore Group Singhbhum Granite (phases I and II) Older Metamorphic Group and Older Metamorphic Tonalite Gneiss
2.2–2.1 2.4–2.3 c. 3.1 c. 3.3 3.5–3.4
Singhbhum Craton (Table 1). As shown in Table 1, Mishra et al. (1999) interpreted the Singhbhum and Kolhan Groups to have formed in the periods of 2400–2300 Ma and 2200–2100 Ma, respectively, whereas the Jagannathpur and Dhanjori lavas of the Dhanjori Group were restricted to the period of 2300–2200 Ma. The age ranges for the Singhbhum and Dhanjori Groups are similar to those that Goodwin (1991) assigned to the same groups in Table 2-26 of his book, but are different from the ages that Mazumder has proposed in his discussion, especially for the Singhbhum Group. Mazumder suggests that the Dhanjori Group formed at ∼2.1 Ga, based on a Sm–Nd whole-rock isochron age of 2072 ± 106 Ma obtained by Roy et al. (2002a) from the Dhanjori Group. However, this age is too imprecise to constrain the timing of the formation of the Dhanjori Group because of its large error. In addition, based on the ∼2.1 Ga Sm–Nd age and a 1619 ± 38 Ma Rb–Sr isochron age obtained Roy et al. (2002b) from the Dalma volcanics that conformably overlies the upper part of the Singhbhum Group, Mazuinder interprets the Singhbhum Group as having developed at some time between 2.1 and 1.6 Ga. This interpretation is established on the basis of his argument that the Dhanjori–Singhbhum succession preserves a normal stratigraphic order and thus that, the Dhanjori Group lying at the bottom should be older than the Singhbhum Group. However, according to Bhattacharya (1992), the Singhbhum and Dhanjori Groups underwent at least four phases of deformation, of which the earliest phase (F1 ) shows tight to isoclinal folds with strongly developed E–W striking axial-plane schistocity and variable axial plunges;
G. Zhao et al. / Precambrian Research 127 (2003) 381–383
the second phase of deformation (F2 ) was the most widespread and thoroughly refolded the F1 structures, and the third (F3 ) and fourth (F4 ) phases locally refolded the F1 and F2 structures. In a region of such complex structure, it would be difficult to confirm that the Singhbhum and Dhanjori Groups still preserve a normal stratigraphic order. The second argument Mazumder raises in his discussion is about correlations involving palaeogeographic settings, sea level changes and their temporal variations between Palaeoproterozoic volcano-sedimentary successions of the Eastern Block (North China) and the Southern Indian Block. Mazumder points out that our original correlations between the Liaohe Group in China and the adjoining Singhbhum, Dhanjori and Kolhan Groups in India are only limited to their gross lithological characteristics, but did not consider palaeogeographic environment, relative sea level change and their temporal variations and other parameters. On the basis of his first argument that the Dhanjori Group is older than the Singhbhum Group, Mazumder then presents a detailed analysis of palaeogeographic setting, sea level change and their temporal variations for the Singhbhum, Dhanjori and Kolhan Groups of the Singhbhum Craton. In response, we have no argument with Mazumder’s suggestion that a similar analysis for the Palaeoproterozoic Liaohe Group will provide a better insight in testing the Archaean to Palaeoproterozoic link of North China and India. However, we consider that lithological/stratigraphic characteristics are also relevant to the analysis of palaeogeographic setting, sea level change and their temporal variations. As shown in Fig. 11 of our original paper (Zhao et al., 2003), the volcano-sedimentary successions of the lower, middle and upper parts of the Liaohe Group are remarkably similar to those of the Singhbhum, Dhanjori and Kolhan Groups, respectively, and thus, the palaeogeographic setting, sea level change and their temporal variations reflected by the Liaohe Group may also be similar to those reflected by the adjoining Singhbhum, Dhanjori and Kolhan Groups. Therefore, we think that lithological/stratigraphic correlations are the first and most important parameters to consider when undertaking reconstruction of ancient continental blocks.
383
Acknowledgements This study was supported by Hong Kong RGC grants (HKU7115/00P and HKU7090/0l P). References Bhattacharya, D.S., 1992. Early Proterozoic metallogeny, tectonics and geochronology of the Singhbhum Cu–U Belt, Eastern India. Precambrian Res. 58, 71–83. Bose, M.K., Chakraborty, M.K., 1981. Fossil marginal basin from the Indian Shield: a model for the evolution of Singhbhum Precambrian belt, Eastern India. Geol. Rundsch. 70, 504–518. Dunn, J.A., Dey, A.K., 1942. The geology and petrology of Eastern Singhbhum and surrounding areas. Mem. Geol. Surv. India 69, 281–456. Goodwin, A.M., 1991. Precambrian Geology. Academic Press, Toronto, 666 pp. Mazumder, R., 2002. Sedimentation History of the Dhanjori and Chaibasa Formations, Eastern India and its Implications. Unpublished Ph.D. Thesis, Jadavpur University, 119 pp. Mazumder, R., Bose, P.K., Sarkar, S., 2000. A commentary on the tectono-sedimentary record of the pre-2.0 Ga continental growth of India vis a vis a pre-Gondwana Afro-Indian supercontinent. J. African Earth Sci. 30, 201–217. Mishra, S., Deomurari, M.P., Wiedenbeck, M., Goswami, J.N., Ray, S., Saha, A.K., 1999. 207Pb/206Pb zircon ages and the evolution of the Singhbhum Craton, Eastern India: an ion microprobe study. Precambrian Res. 93, 139–151. Mukhopadhaya, D., 1976. Precambrian stratigraphy of Singhbhum—the problems and prospectives. Indian J. Earth Sci. 3, 208–219. Naqvi, S.M., Rogers, J.J.W., 1987. Precambrian Geology of India. Oxford University Press, Oxford, 223 pp. Roy, A., Sarkar, A., Jeyakumar, S., Aggrawal, S.K., Ebihara, M., 2002a. Sm–Nd age and mantle source characteristics of the Dhanjori volcanic rocks, Eastern India. Geochem. J. 36, 503– 518. Roy, A., Sarkar, A., Jeyakumar, S., Aggrawal, S.K., Ebihara, M., 2002b. Mid-Proterozoic plume-related thermal event in Eastern Indian craton: evidence from trace elements, REE geochemistry and Sr–Nd isotope systematics of basic-ultrabasic intrusives from Dalma Volcanic Belt. Gondwana Res. 5, 133–146. Sarkar, S.C., Deb, M., 1971. Dhanjori basalts and some related rocks. Quart. J. Geol. Min. Met. Soc. India 43, 29–37. Sarkar, S.N., Saha, A.K., 1962. A revision of the Precambrian stratigraphy and tectonics of Singhbhum and adjacent regions. Quart. J. Geol. Min. Metal. Soc. India 34, 97–136. Zhao, G.C., Sun, M., Wilde, S.A., 2003. Correlations between the Eastern Block of the North China Craton and the South Indian Block of the Indian Shield: an Archaean to Palaeoproterozoic link. Precambrian Res. 122, 201–233.