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In the South Indian basement, several crustal-scale amphibolite facies shear zones occur between high-grade metamorphic units with a different geological history: the EW-trending Moyar Shear Zone (MSZ) is a zone of predominantly dip-slip transport separating the Archaean Dharwar Craton in the north from the late Archaean Nilgiri Block in the south. The NE-SW-trending, dextral-transpressive Bhavani Shear Zone (BSZ) constitutes the southern boundary of the Nilgiri Block in its western part and bounds the southern Dharwar Craton further east. South of the BSZ, the high-grade metasediments and metaintrusives of the Maddukarai region are separated from the 0.6 Ga-metamorphic Madurai Block by the EW-trending dextral Palghat Shear Zone (PSZ). MSZ, BSZ and PSZ are regarded as parts of the prominent Cauvery shear system. The N-S-trending sinistral Kollegal Shear Zone (KSZ), which transects the Dharwar Craton, is cut off by the Cauvery shear system. These shear zones play an important role in reconstructing the position of India within the East Gondwana terrane assembly. A combined Sm-Nd, Rb-Sr and U-Pb isotopic study was carried out on granulite remnants, amphibolite facies (mylonitic) gneisses and pre-, syn- und postmetamorphic intrusives in order to examine the tectonometamorphic evolution of the MSZ, BSZ, PSZ and KSZ. Whole rock data The majority of relic and retrogressed granulites from the MSZ (TDM 2.3–3.1 Ga) and BSZ (TDM 2.6-2.9 Ga) show late Archaean average crustal residence ages. With respect to their LIL-, Nb-depleted tonalitic nature and Nd-model ages, these rocks resemble the neighbouring Nilgiri granulites. Mylonitic gneisses and granulite remnants from the BSZ yielded a Sm-Nd-whole rock-age of 2520 ± 150 Ma (εNd(t) +0.6; MSWD = 2.2), which is interpreted as protolith age. I-Type granites and tonalites, which intruded the MSZ ~620 Ma ago (87Sr/86Sri 0.7039), gave unusually young Nd model ages of 1.8-1.9 Ma suggesting derivation from a Mid- to Neoproterozoic upper mantle source, presumably with minor contribution of an older crust. An allochthonous quarzite (TDM 3.3 Ga) of the BSZ is regarded as counterpart of the Archaean Sargur group, which is exposed in schist belts of the Dharwar Craton. As suggested by geochemical features (LIL-, Nd-rich granitoids) and Neoarchaean-Palaeoproterozoic Nd-model ages (TDM 2.3-3.0 Ga), the PSZ-gneisses show affinity to the adjacent Madurai Block. Sheared orthogneisses from the KSZ show Mesoarchaean average crustal residence ages (TDM 3.2-3.3 Ga) typical for Dharwar Craton gneisses. Mineral dating on granulites Mineral age data of relic granulites from the MSZ, BSZ and PSZ provide evidence for the metamorphic precursor history of the shear zone rocks: gnt-plag-px-granulites from low-strain domains yielded Sm-Ndgarnet- whole rock ages of 2355 ± 22 Ma (εNd(t) -1.4) for the MSZ and 2329 ± 19 Ma (εNd(t) -2.0) for the BSZ, both recording late-stage Palaeoproterozoic granulitisation of the rocks and corresponding with garnet data from the Nilgiri Block. Correlated low εNd-initial values reflect the short time span between crustal genesis and garnet crystallisation. Further Sm-Nd mineral data from BSZ-granulites are between 1275 ± 10 Ma and 1106 ± 48 Ma (garnet/plagioclase-whole rock-pairs; εNd(t) –5.8 to –25.4), indicating a Mesoproterozoic metamorphic imprint. A charnockite from the southern BSZ, which is interpreted as a separate lithological unit, yielded a reproducable Sm-Nd-garnet-whole rock age of 1705 ± 11 Ma (εNd(t) –12.4), presumably recording late Palaeoproterozoic metamorphism. Mineral dating on gneisses and younger intrusives Amphibolite facies rocks with younger fabrics yielded Neoproterozoic to early Palaeozoic mineral age data for the MSZ, BSZ and PSZ: Sm-Nd mineral ages from gneiss-mylonites imply a first stage of early Pan-African shearing in the MSZ ~745 Ma ago (garnet/plagioclase-hornblende-pairs: 743 ± 13 Ma, 747 ± 75 Ma) and in the BSZ ~730 Ma ago (garnetwhole rock-pair: 726 ± 9 Ma). This tectonic stage immediately followed a period of anorogenic alkalimagmatism in the eastern continuation of the BSZ suggesting that it may be attributed to an overall extensive regime. A second stage of late Pan-African shearing in the MSZ at ~620 Ma is constrained by statistically equivalent concordant U-Pb zircon ages that are interpreted to record crystallisation of syndeformative intrusives with Itype characteristics (granite: 616 ± 19 Ma, tonalite: 633 ± 23 Ma). Coeval to slightly younger metamorphic garnet growth in adjacent MSZ-gneisses and -mylonites is reflected by Sm-Nd-garnet-whole rock ages between 624 ± 9 Ma and 591 ± 5 Ma. Subsequent postdeformative cooling in the MSZ is constrained by Rb-Sr micawhole rock ages (muscovite: 594 ± 23 Ma; biotite: 603 ± 12 Ma to 547 ± 7 Ma). The 620 Ma-shearing event in the MSZ predates late Pan-African tectonometamorphism in the BSZ, which, according to garnet crystallisation, occurred ~550 Ma ago (Deters-Umlauf, 1997). Amphibolite facies shear deformation in the PSZ is even younger, as suggested by a Sm-Nd-garnet-whole rock age of 521 ± 8 Ma. A lower limit for the age of ductile shearing in the BSZ is provided by a Sm-Nd-garnet-whole rock-age of 513 ± 5 Ma reflecting postdeformative emplacement of a pegmatitic dyke in mylonitic host gneisses. According to Rb- Sr-mica age dating, postdeformative cooling of the sheared BSZ-gneisses (biotite-whole rock-pairs: 508 to 491 ± 12 Ma) and the undeformed dyke (muscovite-K'feldspar: 504 ± 13 Ma, biotite-K'feldspar: 488 ± 12 Ma) as well as cooling of the PSZ-gneisses (biotite-whole rock-pairs: 486, 487 and 488 ± 12 Ma) may have been slightly diachronous. In summary, the new geochronological data provide evidence for non-synchronousity of late Pan-African tectonometamorphism in the MSZ, BSZ and PSZ. At the time of structurally-controlled amphibolite facies metamorphism, all reworked gneisses had negative εNd(t) values (–24.7 to -9.4) reflecting their earlier crustal evolution. Sinistral shearing along the KSZ is not related to Pan-African processes, but has to be attributed to Palaeoproterozoic metamorphism in the Dharwar Craton: a lower limit for ductile tectonics is provided by a Sm- Nd-garnet-whole rock age of 2388 ± 16 Ma (εNd(t) –7.3). Strikingly younger Rb-Sr biotite-whole rock ages of 2137 ± 52 Ma and 2091 ± 51 Ma may be explained by local reheating of the crust that exceeded the closure temperature of biotite. The new results support the idea of a terrane boundary running along the southern BSZ. This terrane boundary separates the Archaean Dharwar/Nilgiri crustal province with 2.5 Ga metamorphism from the Proterozoic mobile belt of the Madurai province with a 0.6 Ga high-grade imprint. According to geochronological data, South India and Madagascar probably were subjected to different plate-tectonic regimes in the early Neoproterozoic. Late Neoproterozoic syndeformative emplacement of mantle-derived granitoids with crustal contamination both in the MSZ (~620 Ma) and in Central-Madagascar (~ 630 Ma) may point to a neighbouring position of the two East Gondwana continents at that time.