194 JOUR.GEOL.SOC.INDIA, VOL.93, FEB. 2019 JOURNAL GEOLOGICAL SOCIETY OF INDIA Vol.93, February 2019, pp.194-198 Mineralogical Characterisation of Beach Placers at Kantiaghar in Ganjam District, Odisha Bhaktishree Nayak 1 , Ranjan K. Mohapatra 2* , Manoranjan Mangaraj 3 , A. S. Venkatesh 4 , P. N. Behera 3 1 Department of Mineral Engineering, Government College of Engineering, Keonjhar - 758 002, Odisha, India 2 Department of Chemistry, Government College of Engineering, Keonjhar - 758 002, Odisha, India 3 Department of Geology, Utkal University, Bhubaneswar - 751 004, Odisha, India 4 Department of Mineral Engineering, ISM-IIT, Dhanbad - 826 004, Jharkhand, India *E-mail: ranjank_mohapatra@yahoo.com ABSTRACT This paper details with the beach placer deposit of Kantiaghar area of Ganjam district, Odisha. In Odisha, Atomic Mineral Division (AMD) has explored a stretch of about 150 km from south of river Mahanadi to Orissa-Andhra Pradesh border. Here the potential deposits posses a grade range from 5 to 30%. The heavy minerals are present in the beach and dunes around Kantiaghar, which is in the NE of Rusikulya river mouth. The prospect extends in NE-SW direction having a width of about 1000m.Heavy minerals occur up to a depth of 10 m. A total of 12 samples were collected at an interval of half km along the shore of Bay of Bengal. The heavy minerals are mostly of 170 micron size. The average heavy mineral content of Kantiaghar beach is 67%. The heavy minerals constitute sillimanite, ilmenite, garnet, rutile, monazite and zircon. Along with these minerals trace amounts of magnetite and hornblende is also present. Leucoxene and anatase are reported from this beach. The average percentage of sillimanite is 50.15%, ilmenite is 19.47%, garnet is 13.5%, and rutile is 3.7%, monazite is 1.21% and zircon is 0.93%, the number percentage of the heavy minerals clearly shows that t he concentration of sillimanite is high. Based on field relationships and mineralogy it can be interpreted that the river systems draining the Eastern Ghat, their metamorphic associates and basic intrusives account for these deposits. INTRODUCTION Odisha has a number of multimineral placer deposits stretched from Andhra-Odisha border to Dhamara coast. The beach sand deposit reserves are estimated to be of 105 million tonnes (Siddiqui, IREL, 2001). The deposits are beach and sand dune origin. The famous beach sand deposits of Odisha are in Gopalpur and Paradeep. The Kantiaghar prospect is also very promising and limited studies so far have been conducted on Kantiaghar beach sands for its potentiality and qualitative estimates or its genetic aspects. The study of heavy minerals is important as they host good number of minerals of strategic importance in large quantities (Bosworth, 1913). The heavy mineral concentration occurs in beaches due to mechanical processes and the heavies are separated from the lighter minerals by moving water or air that in turn get concentrated as placer deposits. Heavy minerals of beaches are recognized visually by dark colour sands composed of minerals like sillimanite, ilmenite, garnet, rutile, monazite and zircon. The present study area includes Kantiagarh to Rushikulya river mouth that confluences into the Bay of Bengal (Fig.1). The Kantiagarh beach sand prospect extends in NE-SW direction along the Odisha east coast. The beach width varies between 1-1.5 km and heavy minerals are encountered up to the water table. STUDY AREA Locality and Accessibility The study area occurs within the latitude 19°22"-19°27" N and longitude of 85°2"-85°7" E and forms part of the Survey of India Toposheet No: 74A/15. It is located in the Ganjam district, Odisha on the southeastern sea coast of India. The beach width is about 1- 1.5 km. The Bay of Bengal in the southern side and Eastern Ghats Group of rocks in the northern side bound this beach placer prospect. The slope of the beach varies from gentle to steep. The main drainage system of this area is the river Rushikulya, which originates from high lands of Eastern Ghats and joins the sea near Kantiaghar region. Many streams originated from nearby coastal hills join the sea in this area (Fig.2). River Rushikulya and its tributaries form dendritic drainage pattern which helps in carrying a huge amount of source materials for beach placer deposit. The streams are ephemeral in nature and are the major supplier of sediments to this region (Natalia Patyk-Kara, 2007). The area is characterized by a number of sand dunes in which discrete patches of heavy minerals occur as dark bands alternately within the lighter bands. The dark layer thickness varies from 1-10 cm. Quartz and feldspar are the dominant lighter fraction. Fig.1. Heavy mineral bearing area along Ganjam coast 0016-7622/2019-93-2-194/$ 1.00 © GEOL. SOC. INDIA | DOI: 10.1007/s12594-019-1150-8