Record Details

Changes in geotechnical properties of sediments from the Central Indian Basin induced by disturbance experiment

DRS at CSIR-National Institute of Oceanography

View Archive Info
 
 
Field Value
 
Title Changes in geotechnical properties of sediments from the Central Indian Basin induced by disturbance experiment
 
Creator Khadge, N.H.
 
Subject sediments
geotechnology
sediment properties
shear strength
meiobenthos
ecosystem disturbance
siliceous sediments
deep-sea mining
ferromanganese nodules
 
Description During the Indian Deep-sea Environment Experiment (INDEX) conducted in the Central Indian Basin to simulate nodule mining activity, the sediments were physically disturbed, lifted from the seafloor, and then redeposited to study the effects of sediment redistribution on geological, chemical and biological characteristics of benthic environment. The first monitoring cruise, 44 months after the experiment, was part of long-term observations for restoration of conditions. This study describes the effects of the experiment on geotechnical properties of sediments measured in predisturbance, postdisturbance and monitoring phases. To compare the effects, sediment cores were collected from the same locations during the three phases. Siliceous, fine-grained sediments from the study area showed change in geotechnical properties induced due to the disturbance. Marginal increase in natural water content and significant reduction in undrained shear strength at the 0-5 cm sediment layer of cores from the tow zone during postdisturbance was observed. However, during the monitoring phase, an increase in shear strength and reduction in water content was noticed, which might indicate that the sediments are gradually acquiring predisturbance characteristics. The study also revealed that the meiofaunal density has a positive correlation with the water content, but a negative relationship with the shear strength of these siliceous sediments. Specific gravity of solids and porosity showed marginal change, whereas wet density remained unchanged.
 
Date 2008-02-22T05:30:11Z
2008-02-22T05:30:11Z
2005
 
Type Journal Article
 
Identifier Marine georesources and geotechnology, Vol.23; 401-417p.
http://drs.nio.org/drs/handle/2264/938
 
Language en
 
Rights Copyright [2005]. It is tried to respect the rights of the copyright holders to the best of the knowledge. If it is brought to our notice by copyright holder that the rights are voilated then the item would be withdrawn.
 
Publisher Taylor and Francis