Garnet mineral chemistry as a provenance indicator for the modern beach sediments of north-eastern Andhra Pradesh, east coast of India

917-924The provenance of garnets from coastal sediments between the Nagavali and Vamsadhara river mouths, east coast of India were studied using garnet molecular proportions. This mineral chemical electron micro probe analytical data have been correlated with published garnet chemistry from various litho units of the eastern ghats granulite belt to understand provenance. The present study reveals that the garnets with molecular proportions of almandine (Alm. 50-56%), pyrope (Py. 33-43%) and traces of grossular (Gr. 5%) were derived from charnockite suite of rocks. The major portion (83%) of the studied garnets is derived from khondalite (metapelitic) suite of rocks susceptible for physical weathering due to large areal exposure and minor proportion (17%) is derived from charnockite suite of rocks which due to less coverage in drainage basis is not susceptible for mechanical weathering

Agglutinated foraminifera from the Chilka Lake, Orissa, east coast of India

531-538<span style="font-size:10.0pt;mso-bidi-font-size: 11.0pt;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;="" mso-bidi-language:hi"="" lang="EN-GB">Sediment and water samples were collected at 50 stations from the Chilka Lake during May and December, 2009 for foraminiferal studies and determination of important sediment and water parameters. The salinity ranges from 27.9 to 40.9 ‰, the temperature range is from 23.6o to 32o C, the dissolved oxygen content ranges from 6.4 to 8.2 ml/L and the substrate of the lake is characterized by sand, silty sand, muddy sand, clayey sand and sandy clay. Sand dominates the other types of substrate towards the mouth of the channel at Arakudha Village. Organic matter content of the sediment varies from 0.31 to 2.0 %. Fifteen agglutinated foraminiferal species - <i style="mso-bidi-font-style: normal">Ammobaculites agglutinans, A. directus, A. exiguus, Ammotium fragile, Gaudryina exilis, Haplophragmoides canariense, Jadammina macrescens,<span style="font-size:10.0pt;mso-bidi-font-size: 11.0pt;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;="" mso-bidi-language:hi"="" lang="EN-GB"> Miliammina fusca, M. fusca var., Reophax dentaliniformis, Textularia earlandi, Tiphotrocha kellettae, Trochammina advena, T. hadai and T. ochracea of which <i style="mso-bidi-font-style: normal">Miliammina fusca, M. fusca var. and Ammobaculites exiguus are of abundant occurrence tolerating relatively higher salinity and temperature. </span