A new report on the occurrence of zeolitites in the abyssal depths of the Central Indian Basin

Abstract

Forty-two indurated slabs of zeolites collected from the abyssal depths of the Central Indian Basin have been studied. The slabs show characters similar to harmotome-rich scorias of the Society Ridge and phillipsite slabs in the Pacific Ocean. These slabs are described as zeolitites in the present paper, as they represent dominantly the phillipsite-harmotome group of minerals. Ferromanganese oxides occur as specks and dentrites over these slabs. Also the zeolitic material form nuclei for ferromanganses nodules. The zeolitites exhibit various degrees of weathering, which seems to have no effect on the mineralogy. Pumice clasts are entrapped within the zeolitites. Bioturbation is evident from the intense macro and micro burrowing structures and porous nature of the samples. Geographical distribution of zeolitites in the basin is restricted to south of 10 degrees S. Further, they closely occur in the vicinity of major fracture zones and seamounts. The tranformational conditions from volcanic precursors to zeolitites are suggested