Saluvankuppam coastal temple excavation and application of soil micromorphology

The 26 December 2004 tsunami exposed an inscription of the 10th century engraved on a rock boulder at Saluvankuppam, 6 km north of Mamallapuram. The inscription indicates the existence of a Subramanya temple. The temple and the mound around the granite inselberg were excavated by the Archaeological Survey of India, Chennai Circle. The excavation exposed the entire Subramanya temple complex constructed over a period of time (4th/5th CE to 12th/13th CE). The temple complex and the litho sections reveal phases of temple building activity. The cement and lime used for the temple complex contain fragments of shells. Soil micromorphology technique was applied to understand the type of textures and fabric in soil sediments, bricks, potsherds, well rims, bone fragments, etc., using a polarized microscope. Thin sections of the laterite bricks which formed the foundation indicate high content of hematite, magnetite, kaolinite patches and the porosity of the laterite brick varies from 5% to 10% only, whereas thin sections of potsherds indicate that the firing temperature was fairly low and that the pots were well fired. Geoarcheology study of this temple complex indicates that a number of naturally occurring raw materials have been used for constructing this temple that were locally available

PALAEOFLOOD RECORDS FROM UPPER KAVERI RIVER, SOUTHERN INDIA: EVIDENCE FOR DISCRETE FLOODS DURING HOLOCENE

Abstract: A record of six discrete middle Holocene floods has been established based on sedimentological and stratigraphical studies in the upper Kaveri catchment at Siddapur. The flood events are represented by six discrete, sharp-bounded, sand-silt couplets. Texturally and geochemically the suite of couplets is quite distinct from the overlying and underlying structureless fluvial deposits. Based on OSL ages the suite of couplets cover the Holocene from ~8 to ~2 ka. Such evidence is not present or reported from any other river originating in the Western Ghat in the Indian Peninsula. We argue that the six couplets represent short-term, high discharge events or flash floods. The initiation of this phase of flash floods broadly corresponds with the southward migration of ITCZ and a gradual decline in Indian summer monsoon precipitation starting at ~7.8 ka. Comparison of the elevation of the highest couplet with the high flood level (HFL) of the 1961 extraordinary flood on Kaveri demonstrates that the 20th century flood was higher than the mid-Holocene palaeofloods

Preservation of plant-wax biomarkers in deserts:implications for Quaternary environment and human evolutionary studies

Analysis of plant‐wax biomarkers from sedimentary sequences can enable past environmental and hydrological reconstruction and provide insights into past hominin adaptations. However, biomarker preservation in desert contexts has been considered unlikely given the sparse nature of the vegetation within the landscape. Here we evaluate the preservation of n‐alkanes and fatty acids collected from four depositional sequences associated with archaeological contexts in the Nefud Desert, Saudi Arabia, and the Thar Desert, India. Pleistocene and Holocene samples were selected to understand the effects of age on preservation. The results of molecular distribution patterns and indices, particularly the high carbon preference index and average chain length, show the preservation of plantwax biomarkers in both the Holocene and Pleistocene desert sequences, while δ13C values and organic content provide insights into the vegetation contributing to the plant‐wax organic pool. This study provides a baseline for understanding human–environment interactions and for reconstructing changes in arid land habitats of relevance to hominins during the Quaternary.peer-reviewe

Paleopedology of ferricrete horizons around Chennai, Tamil Nadu, India

Algunos suelos alrededor de Chennai, Tamil Nadu están representados por horizontes de ferricreta, que pueden estar relacionados con el lecho rocoso subyacente. En el presente estudio, los Suelos Rojos y las ferricretas han sido estudiados en cuatro diferentes sitios: Red Hills, Vaiyapur, Uttukkadu y Pallavaram, que fueron formados de diferente roca parental. Los Suelos Rojos y ferricretas cerca de Vaiyapur y Red Hills se formaron a partir de la arenisca y lutita Gondwana Superior, mientras que alrededor de Pallavaram se formaron a partir de charnockitas precámbricas. En este artículo se presentan la morfología, micromorfología y geoquímica de ferricretas y Suelos Rojos. Los elementos de la microfábrica en secciones delgadas pulidas ofrecen una base para la interpretación de los procesos involucrados en la formación de Suelo Rojo y ferricreta. La micromorfología del suelo Rojo y la ferricreta revela un alto contenido de minerales de arcilla como gibsita, esmectita, haloisita y caolinita. La mineralogía de óxidos de Fe está representada por hematita, limonita, goethita y magnetita. La pedogénesis ha producido segregación de hierro, que se formó tanto interna como externamente en una gran variedad de colores. Las grietas y fracturas están rellenas de caolinita o hematita. Algunas de las fracturas se encuentran revestidas de óxido de manganeso negro, que representa la fase de depositación final. Con base en la geomorfología, se establece que los suelos datan del período Neógeno tardío al Cuaternario temprano. Se interpreta que las condiciones climáticas eran más húmedas que las actuales

The megalithic burial potteries of Siruthavoor: micromorphology

Festschrift for Professor Vidula Jayaswa

<smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="country-region"><smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="City"><smarttagtype namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="place"> Trace metals concentrations in the sediment cores of estuary and tidal zones between Chennai and Pondicherry, along the east coast of India </smarttagtype></smarttagtype></smarttagtype>

141-149Four sediment cores collected from the water depths varying between 1.0 and 1.50 m in estuarine and tidal zones between Chennai and Pondicherry, along the Tamil Nadu coast, were analysed for major elements (Fe and Al), trace metals (Mn, Zn, Cr, Co, Pb and Ni), carbonate and organic carbon contents to understand the behaviour of trace metals and their probable sources. The results reveal that Ni and Cr are higher in the Adyar estuarine sediments compared to other three sites at Muttukadu, Mamallapuram and Marakkanam. Higher content of Ni and Cr in the entire core sediments of Adyar points to mixing of sediments and bioturbation. Calculated enrichment factor (EF) with respect to upper continental crust (UCC) values show that analysed sediments are depleted in Mn, Co, Pb and enriched in Ni, Cr. Adyar estuary is highly contaminated especially with respect to Ni and Cr due to metal inputs from anthropogenic activity. Higher Fe and Mn content in Mamallapuram sediments may be due to the variability of source rock exposed in this region. The EF values of Marakkanam sediments reveal unpolluted nature and the positive correlation among Fe, Mn and other trace metals indicate the influence of early diagenetic process