CHARACTERISTICS OF CRETACEOUS RED SOIL

The marine Cretaceous transgressions of the Indo-Pacific Sea covered the continental area of 450 square kilometers cantered on Ariyalur which causes the formation of various kinds of sedimentary rocks and the preservation of marine invertebrates’ fossils. So this area is called a heritage site with a field museum and is known to be the Cretaceous park of Tamilnadu South India. The cretaceous formation of the Ariyalur is one of the best-developed sedimentary sequences in south India. The cretaceous system of the Cauvery basin consists of a shallow marine sequence with a rich faunal succession of Albian – Mastrichtion (Blan ford 1862) stratigraphy of this formation and he divided the litho units into three groups; Uttatur Trichinopoly and Ariyalur. These three groups are largely disconformable and occasionally unconformable at places. The late cretaceous sediments are exposed in the western part of the study and classified into Uttatur Trichinopoly and Ariyalur formations with a maximum thickness of 900m 600m and 1500m respectively. The Trichinopoly formation is unconformably overlaying the Uttatur formation. And also Uttatur for the rest part of the Cretaceous age.