Abstract Dharwar Craton of southern peninsular India is one of the significant Archean cratons in the world with well developed greenstone belt sequences representing plume-arc accretionary tectonics. The eastern Dharwar Craton (EDC) is endowed with excellent gold mineralization which is being mined and the greenstone belt lithounits among which majority of them represent the convergent margin processes. The Neoarchean Kadiri greenstone belt of EDC consists of an array of mafic, intermediate and felsic volcanic rocks among which the mafic rocks exhibit a wide range of silica (49.74–65.19 wt.%), high LILE, HFSE including the Nb contents (7−15 ppm) that are classified as Nb-enriched basaltic andesites (NEBA). Moderate composition of SiO2 (57−63 wt.%) along with higher MgO (3.96–7.58 wt.%), Cr (44−890 ppm) and Ni (22−491 ppm) contents distinguish some of the intermediate rocks as Mg-andesites. The petrographic characteristics along with higher silica (63−75 wt.%), Na2O (2.21–4.01 wt.%) and low K2O (0.7–3.35) classify the associated felsic volcanic rocks as sodic adakites. Abundance of K-feldspar phenocrysts and higher K2O content (1.19–7.0 wt.%) in some adakites identify them as potassic adakites. The geochemical characteristics of the calc-alkaline andesite-dacite-rhyolites (ADR) reflect on typical island arc environment involving the processes of fractional crystallization and crustal contamination in an active continental margin environment. The NEBA and Mg-andesites are the products of hybridized mantle wedge under the influence of slab fluids/melts whereas the Na-adakites are the slab melts erupted within the oceanic domain and the K-adakites were emplaced under the influence of continental crust during the migration of the island arc towards the continental margin. Beside the generation of various types of volcanic rocks, these convergent margin processes have played a significant role in the generation and mobilization of gold mineralized fluids, which are being mined from some greenstone belts of EDC.

中文翻译：

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印度达尔瓦尔克拉通东部 Neoarchen Kadiri 绿岩带地球动力学过程的演化：对迁移弧岩浆作用的影响

摘要 印度半岛南部的达尔瓦尔克拉通是世界上重要的太古代克拉通之一，绿岩带层序发育良好，代表了羽弧增生构造。东达尔瓦克拉通 (EDC) 具有正在开采的优良金矿化和绿岩带岩性单元，其中大部分代表会聚边缘过程。EDC 的新太古代 Kadiri 绿岩带由一系列基性、中性和长英质火山岩组成，其中基性岩表现出广泛的二氧化硅（49.74-65.19 wt.%）、高 LILE、HFSE，包括 Nb 含量（7- 15 ppm）被归类为富含 Nb 的玄武质安山岩 (NEBA)。中等成分的 SiO2 (57-63 wt.%) 以及较高的 MgO (3.96-7.58 wt.%)，Cr (44-890 ppm) 和 Ni (22-491 ppm) 含量将一些中间岩石区分为镁安山岩。岩相特征以及较高的二氧化硅 (63-75 wt.%)、Na2O (2.21-4.01 wt.%) 和低 K2O (0.7-3.35) 将相关的长英质火山岩归类为钠化埃达克岩。一些埃达克岩中丰富的钾长石斑晶和较高的 K2O 含量 (1.19–7.0 wt.%) 将它们识别为钾质埃达克岩。钙碱性安山岩-英安岩-流纹岩（ADR）的地球化学特征反映了典型的岛弧环境，包括活动大陆边缘环境中的分步结晶和地壳污染过程。NEBA和Mg-安山岩是板片流体/熔体作用下杂化地幔楔的产物，而Na-埃达克岩是大洋域内喷发的板片熔体，K-埃达克岩是在大陆地壳作用下侵位的。岛弧向大陆边缘迁移。除了各种类型的火山岩的生成外，这些会聚边缘过程在金矿化流体的生成和流动中发挥了重要作用，金矿化流体正在从 EDC 的一些绿岩带中开采出来。