The Purna alluvial basin of central India, infilled largely with areno-argillaceous sediments of Quaternary age, is also marked by occurrences of both pedogenic and non pedogenic calcretes of diverse shape and size. The previous includes nodular, laminar, hardpan and root calcretes along with rhizolith balls and rhizospheres, whereas non pedogenic type is represented by groundwater calcretes. These calcretes have been investigated for their morphological details, lithological associations in both vertical and lateral profiles of the alluvial deposit and paleoclimatic reconstructions. This study shows that the area under investigation has undergone through subtropical, arid and semiarid climatic conditions having low to medium humidity, high rainfall and evaporation that favored formation of various types of calcretes. Nodular calcretes, the most dominant morphotype, are preserved in a wide spectrum of lithology and fluvio-lacustrine environment. To some extent, their formation is controlled by parent material, irregular rainfall and mild temperature. Rapid accumulation of carbonate material, in and around the plant roots giving rise root calcretes of various shapes and size is a common phenomenon in warm and dry climatic conditions. Both hardpan and groundwater calcretes are formed due to CaCO₃ precipitations in humid condition having heavy rainfall. Besides, the later also indicates arid to semiarid conditions facilitating the movement of Ca rich solution in the unconsolidated sediments through capillary action that later deposited calcium carbonate in the voids during wet and dry conditions. Well preserved rhizolith balls and rhizospheres in the palaeosols, constituting together the lower part of succession in almost entire alluvial basin, acts as potential paleoclimatic indicator.

印度中部的Purna冲积盆地中，充斥着第四纪的非泥质沉积物，其特征还在于有不同形状和大小的成岩和非成岩的钙质。前者包括根瘤球，根际球和球根，层状，硬盘和根，而非成岩类型则以地下水为代表。对这些具体的形态进行了研究，研究了冲积沉积物的垂直和横向剖面的岩石学联系以及古气候重建。这项研究表明，所调查的地区经历了亚热带，干旱和半干旱气候条件，湿度低至中湿度，高降雨和蒸发，有利于形成各种类型的钙质。球状结节 最主要的形态型保存在广泛的岩性和河流湖相环境中。在某种程度上，它们的形成受到母体物质，不规则降雨和温和温度的控制。在温暖和干燥的气候条件下，植物根部内和周围碳酸盐物质的快速积累会形成各种形状和大小的根生根钙质。由于碳酸钙的作用，形成了硬顶和地下水的碎屑_3个降水在潮湿的条件下有很多降雨。此外，后者还指示干旱至半干旱条件，通过毛细作用促进未固结沉积物中富钙溶液的运动，毛细作用随后在潮湿和干燥条件下将碳酸钙沉积在空隙中。古土壤中保存完好的根际球和根际，几乎构成了整个冲积盆地演替的下部，是潜在的古气候指示剂。