Samples of recent to Miocene fish and marine mammal bones from the bottom of the Atlantic and Pacific Oceans and Miocene Maikop deposits (Transcaspian region) are studied by X-ray diffraction technique combined with chemical and energy-dispersive analyses. Changes of lattice parameters and chemical composition of bioapatite during fossilization and diagenesis suggest that development of skeletal apatite proceeds from dahllite-type hydroxyapatite to francolite-type carbonate-fluorapatite. It is assumed that jump-type transition from dahllite to francolite during initial fossilization reflects replacement of biogeochemical reactions in living organisms, which are subject to nonlinear laws of nonequilibrium thermodynamics, by physicochemical processes according to the linear equilibrium thermodynamics.

Supplement to: Nemliher, J G; Baturin, Gleb N; Kallaste, T E; Murdmaa, Ivar O (2004): Transformation of hydroxyapatite of bone phosphate from the ocean bottom during fossilization. Translated from Litologiya I Poleznye Iskopaemye, 2004, 5, 539-551, Lithology and Mineral Resources, 39(5), 468-479