Confocal laser scanning fluorescence microscopy of Botryococcus alginite from boghead oil shale, Boltysk, Ukraine: selective preservation of various micro-algal components

Confocal laser scanning fluorescence microscopy (LSM) has exceptional poten tial for resolving micrometer scale morphological details within fluorescin g macerals (e.g. alginite) of hydrocarbon source rocks and oil shales. This investigation of well preserved Botryococcus alginites from a Paleogene bo ghead oil shale from central Ukraine clearly illustrates that LSM can effec tively resolve microalgal cellular organization. A dominance of highly resi stant, outermost cell walls in Botryococcus confirms that selective preserv ation was an effective process during kerogen formation. Three dimensional serial section compilations of images taken through Botryococcus alginites reveals a number of cellular features including: (i) micro-layering within resistant outer cell walls; (ii) preservation of resistant, very thin, oute r walls of apical cells and; (iii) stacks of successive thimble-shaped laye rs and funnel-shaped cups which comprise the resistant stalk framework of f ossilized compound colonies. LSM also discloses preservation of pairs of 'r eproducing' Botryococcus cells consisting of outer resistant walls enclosin g mainly unstructured, granular organic matter in the 'cell contents region '. Some serial images from these areas do, however, show evidence for cellu lar organization and possible selective preservation of possible resistant biomacromolecules derived from aplanosphores or zoospores. (C) 1999 Elsevie r Science Ltd. All rights reserved.