Dharwar craton (DC), by far the largest geological domain in South Indian Shield, occupying about 0.5 million sq. km area, is well-studied terrain both for regional geoscientific aspects and as part of mineral exploration over several important blocks such as the greenstone belts, ultramafic complexes, granite-gneissic terrain and the Proterozoic sediments of Cuddapah basin. The re-look into regional gravity data offers several insights into nature of crust, sub-divisions within the craton, bedrock geology in the covered areas and mineral potentiality of this ancient and stable crust. The regional gravity profiles drawn across the south Indian region mainly suggest that the area can be divided into five domains as Western Dharwar craton (WDC), Central Dharwar craton (CDC), Eastern Dharwar craton (EDC 1), transitory zone of EDC (EDC 2) and Eastern Ghats mobile belt (EGMB) areas. The Bouguer gravity anomaly pattern also questions some of the earlier divisions like eastern margin of Chitradurga schist belt between the WDC and EDC and the boundary of DC with southern granulite terrain (SGT) as they do not restrict at these main boundaries. In this study, mainly four issues are addressed by qualitative and quantitative analysis of regional gravity data and those revealed significant inferences. (1) A distinct gravity character in central part of south Indian shield area occupying about 60, 000 sq. km, suggests that the transitory crustal block, faulted on both sides and uplifted. This area designated as central Dharwar craton (CDC) is characterized with schist belts having characters of both parts of western and eastern Dharwar craton. This inference also opens up the debate about the boundary between western and eastern parts of the craton. Another significant inference is the extension of major schist belts beneath both Deccan volcanic province (DVP) in northwestern part and Cuddapah basin (CB) in southeastern part. (2) Eastern Dharwar craton is reflected as two distinct domains of different gravity characters; one populated with number of circular gravity lows and a few linear gravity high closures indicative of plutonic and volcanic activity and another domain devoid of these intrusive younger granites or schist belts. (3) Large wave length gravity highs occupying thousands of sq.km area and those not relatable to surface geology in eastern Dharwar craton that may have significance for mineral exploration. (4) Gravity data was subjected to further processing like two dimensional modeling which have yielded insights into crustal architecture beneath the Dharwar craton, crustal scale lineaments, craton-mobile belt contact zone and younger intrusives.

中文翻译：

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南印度地盾 Dharwar Craton 的重力

Dharwar craton (DC) 是迄今为止南印度地盾中最大的地质区域，占地约 50 万平方公里，是区域地球科学方面和几个重要区块（如绿岩）矿产勘探的一部分，经过充分研究的地形带、超镁铁质杂岩体、花岗岩-片麻岩地形和库达帕盆地的元古代沉积物。重新研究区域重力数据提供了对地壳性质、克拉通内的细分、覆盖区域的基岩地质以及这个古老而稳定的地壳的矿物潜力的若干见解。整个印度南部地区绘制的区域重力剖面主要表明该地区可分为五个域，即西达尔瓦尔克拉通 (WDC)、中达尔瓦尔克拉通 (CDC)、东达尔瓦尔克拉通 (EDC 1)、EDC (EDC 2) 和东高止山脉移动带 (EGMB) 区域的过渡区。布格重力异常模式也质疑了一些早期的划分，如 WDC 和 EDC 之间的 Chitradurga 片岩带东部边缘以及 DC 与南部麻粒岩地形 (SGT) 的边界，因为它们不限制在这些主要边界上。在本研究中，主要通过区域重力数据的定性和定量分析解决了四个问题，并揭示了重要的推论。(1) 南印度地盾区中部约 60, 000 平方公里的明显重力特征表明过渡地壳块体两侧断裂并隆起。该地区被指定为中达尔瓦尔克拉通 (CDC)，其特征是片岩带具有达尔瓦尔克拉通西部和东部的特征。这一推论也引发了关于克拉通西部和东部边界的争论。另一个重要的推论是西北部德干火山省 (DVP) 和东南部库达帕盆地 (CB) 下方的主要片岩带的延伸。(2) 东达尔瓦克拉通反映为两个不同重力特征的不同域；一个有许多圆形重力低谷和一些线性重力高封闭区，表明深成岩和火山活动，另一个没有这些侵入性的年轻花岗岩或片岩带。(3) 达沃克拉通东部面积达数千平方公里的大波长重力高点和与地表地质无关的可能对矿产勘探具有重要意义的高点。