Titre du document / Document title

Microbiological transformation of basalts of the great fissure tolbachik eruption of 1975-1976 (Kamchatka) into lesukite, Al²(OH)⁵Cl.2H²O, and other phases of bauxites

Auteur(s) / Author(s)

FILATOV S. K. ; VERGASOVA L. P. ; STEPANOVA E. L. ; KUTUZOVA R. S. ; POLYAKOVA I. G. ;

Résumé / Abstract

Lesukite, ideally Al²(OH)⁵Cl . 2H²O, occurs in fumarole fields of the Great Fissure Tolbachik Eruption (GFTE, 1975-1976), Kamchatka peninsula, Russia. It is formed as a result of thermal, exhalative and biological influence on volcanic basalt rock. According to the high temperature X-ray powder diffraction and thermal gravimetric data, a parameter of the lesukite decreases under heating reversibly in the 20-90 °C temperature interval and half-reversibly in the 20-140 °C interval. The amount of the weight loss is 15 %, and only half of that is reversible. Heating above 140 ′ 5 °C causes the decomposition of the mineral. Such thermal behavior can be explained by the step-by-step loss of water from the structure. The gibbsite, Al(OH)³, was also found among the lesukite sediments. Besides, there is an amorphous phase enriched by aluminum (alumogel). So, there are bauxite sediments accumulated on the New Tolbachik cones. The research has shown that the transformation of erupted rock was participated with microbus community: the autotrophic bacteria transforming sulfur and iron, algae and polymorph microorganisms like Metallogenium-Siderococcus.

Revue / Journal Title

Zapiski Vserossijskogo mineralogičeskogo obŝestva   ISSN 0869-6055 

Source / Source

2004, vol. 133, n^o3, pp. 1-11 [11 page(s) (article)]

Langue / Language

Russe

Editeur / Publisher

Nauka, Sankt-Peterburg, RUSSIE, FEDERATION DE  (1992) (Revue)

Localisation / Location

INIST-CNRS, Cote INIST : 4673, 35400012582681.0010