Sediment distribution and placer mineral enrichment in the inner shelf of Quilon, SW coast of lndia

Abstract

<span style="font-size:14.0pt;line-height: 115%;font-family:" times="" new="" roman";mso-fareast-font-family:"times="" roman";="" color:black;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" hi"="" lang="EN-IN">Surficial sediment samples from the innershelf off Quilon, SW coast of India have been examined for the sediment type, placer distribution and titanium content. A major portion of the innershelf is covered with sands and silty clays. The southern shelf and outer-innershelf of the northern shelf are covered with moderately sorted medium sand whereas poorly sorted silty clays occur mostly in the northern shelf. The total heavy mineral content in the shelf varies from 1 to 12%. It is generally seen that high percentage of heavy mineral occurs in the sandy sediments. The results of Q-mode factor analysis indicate the spatial distribution of factors, which reflect the grain-sorting pattern of heavy minerals in the shelf. The distribution of titanium shows marked variation with texture of the sediments. The titanium content is higher in the southern shelf region where sandy sediments dominate. The near- innershelf of the northern shelf contains higher concentration of titanium with a decreasing tendency towards the outer- innershelf indicating the lithogenous &nbsp;origin. The distribution of heavy minerals and titanium in the innershelf indicates net sediment movement towards the northern shelf region where rich concentrations of placer minerals occur along the coast.</span>