Research Article ISSN 2278–0092 International Journal of Advances in Earth Sciences, Volume 3, Issue 2, 2014, 52-60 © Copyright 2014, All rights reserved Research Publishing Group www.rpublishing.org 52 Clay Mineral Study in Tertiary Sediments from Bhatia and Jaigarh Creek, Ratnagiri, M.S. (India) Suryawanshi R A *1 , Sawant P.T. 2 and Golekar R B 3 *1 Department of Geology, Yashwantrao Chavan College of Science Karad, 415124 (M.S.), India E-mail: ravianand55@gmail.com Tele Fax No.: +912164-271356 2 Rajarshi Shri Shahu Arts, Science and Commerce College Pathri, Taluka - Phulambri, Dist. Aurangabad, (M.S.), India E-mail: sawantpt@gmail.com 3 Department of Civil Engineering, Shri Chhatrapati Shivaji College of Engineering, Rahuri, Dist. Ahmednagar - 413706 (M.S.), India Tele Fax No.: +912426-251200 E-mail: rbgolekar@gmail.com, rushikeshgolekar@scscoe.org Received August 12, 2014; Accepted October 4, 2014 Abstract The paper presents clay mineral studies of tertiary sediments from Bhatia and Jaigarh Creek, Ratnagiri, Maharashtra state, India. Representative samples from the well sections have been collected by standard method for XRD, IR, SEM and geochemical studies. In present investigation sandstone, grey shale, carbonaceous shale, lignite along with basalts and Laterites as major litho units are observed in the area under study. In the present investigations Kaolinite, Montmorillonite, Chlorite and Vermiculite as clay minerals is detect in the sediments. The chemical analysis result of clay minerals shows that the mean concentration of SiO 2 (51.53 %) followed by Al 2 O 3 (24.81 %), Fe 2 O 3 (4.79 %), TiO 2 (4.53 %), MgO (1.05 %), Na 2 O (0.81 %), CaO (0.39 %) and K 2 O (0.36 %) was found. As is evident from the clay mineral studies, the Tertiary clay indicate more of secondary, estuarine environment, where in clay minerals after their formation in the vicinity areas have been transported and deposited. Keywords: Tertiary sediments, Clay minerals, XRDs, Infrared Spectra, geochemistry, Bhatia and Jaigarh Creek, Ratnagiri, M.S. (India) 1. Introduction The area under present investigations is occupied by the basaltic lava flows capped with laterites and in subordinate amount, by bauxite (Suryawanshi and Golekar 2014). All along the coast, consolidated and unconsolidated Quaternary sediments are developed while mud flats are present at the mouth of rivers. Tertiary sediments are mainly exposed in the well sections which is a major lithological unit considered for present investigations. Regional geological map of the study area has presented in figure 1. The composition of clay mainly depends on two factors, viz., chemical composition of parent minerals and physico-chemical environment in which alteration takes place. The source and environment of deposition are the important factors controlling the clay mineralogy and their distribution (Grim, 1958). However, the environment plays a significant role in post - depositional changes in clayey sediments (Weaver, I958; Gibbs, 1977). The clay mineral facies in sedimentary assemblage can be well understood with regards to geological environment, source conditions, environmental parameters, which are dependent on geology, geography and climate. The clay mineral composition mainly depends on the provenance (Jonas, 1975; Powers, 1957). 1.1 Study area The study area is a costal belt of about 70km in length extending from Bhatia creek (Latitude 16 0 55 ” N and Longitude 72 0 30 ” E) in the South and Jaigarh creek (Latitude 17 0 30 ” N and Longitude 73 0 25 ” E) in North. The study area included in survey of India toposheet nos. 47 G/3, G/7, G/8 and H/5 (Fig. 2).