NOPR Collection:

Design of a gravity corer for near shore sediment sampling

2016-12-01T10:06:36Z

Title: Design of a gravity corer for near shore sediment sampling Authors: Bhat, S T; Sonawane, A V; Nayak, B U Abstract: For the purpose of geotechnical investigation a gravity corer has been designed and fabricated to obtain undisturbed sediment core samples from near shore waters. The corer was successfully operated at 75 stations up to water depth 30 m. Simplicity of design adopted ensures minimum time in assembling and dismantling the corer in the field. Page(s): 83-84

Geotechnical properties of deep-sea sediments from Central Indian Ocean Basin

2016-12-01T10:02:19Z

Title: Geotechnical properties of deep-sea sediments from Central Indian Ocean Basin Authors: Khadge, N H Abstract: Physical and geotechnical properties of 2 sediment cores from the nodule rich area of the Central Indian Ocean Basin are studied to know the sediment characteristics. Average water content of sediment from 2 deep-sea cores is 289% with 151% as liquid limit and 103% as plastic limit. Average values of wet density, porosity and specific gravity are 1.21 x 10(6) g.m-3, 87%, and 2.35 respectively. Organic carbon content is < 1% for both the cores. Sand, silt and clay contents are 16, 32 and 52% respectively. Sediments are siliceous ooze, medium to high plastic and fine grained in nature. The properties are quite comparable to those reported for Pacific Ocean sediments. Page(s): 80-82

Dispersal pattern of clay minerals in the sediments of Nizampatnam bay, east coast of India

2016-12-01T09:57:58Z

Title: Dispersal pattern of clay minerals in the sediments of Nizampatnam bay, east coast of India Authors: Rao, P Sreenivasa Abstract: Constituent minerals of the clays were (from X-ray diffraction) montmorillonite, illite, kaolinite and chlorite. Montmorillonite is the predominant mineral which constitutes > 80% of the clay minerals in most of the sediments. Illite is the next abundant mineral varying from 5-22%. Kaolinite and chlorite are least abundant with concentrations well below 10%. Lateral distribution pattern of the clay minerals shows an increase in smectite with concomitant decrease in illite and kaolinite from the coast to the shelf. A greater contribution of the clay fraction appears to have been derived from the erosion of alkaline rich rocks in the upper reaches of Krishna drainage basin. Page(s): 77-79

Uptake and bioconcentration of copper and zinc by the mollusks Saccostrea cucullata (Born) and Cerithium rubus (Desh) from the coastal waters of Bombay

2016-12-01T09:48:24Z

Title: Uptake and bioconcentration of copper and zinc by the mollusks Saccostrea cucullata (Born) and Cerithium rubus (Desh) from the coastal waters of Bombay Authors: Kumari, L Krishna; Nair, Vijayalakshmi R Abstract: Rate of uptake increased linearly during the initial period of 20-30 days. Compared to the gastropod, the rate of uptake in oyster was 2.2 and 9.4 times more respectively Cu for Cu andZn. In oysters collected from a polluted area off Bombay coast, high levels of Zn (av 4522-mu-g.g-1dry wt) and Cu(av 420-mu-g.g-1 dry wt) were observed. The concentrations of these metals in the snails were low (av 216 and 126-mu-g.g-1 dry wt respectively). Page(s): 74-76