The Quaternary deposits of Purna alluvial basin are mainly represented by areno-argillaceous sediments with good development of calcretes in both lateral and vertical profiles. Calcretes from thirteen river cut sections, lying along the main channel of Purna River, have been studied for their morphological characteristics. Total six morphotypes, i.e., nodular calcrete, laminar calcrete, hardpan calcrete, root calcrete, rhizolith balls and vein calcrete, have been identified, of which the first was dominant. The lithological association of various calcretes reveals their development mostly in fine- to medium-grained sediments, whereas root calcretes and rhizolith balls are mostly restricted to clayey-silty units. The predominance of calcretes in entire basin indicates the presence of the pedogenic activities under arid to semiarid climatic conditions during the deposition of sediments.
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