Amino acids of the early Paleozoic brachiopods in the Timan-North Urals basin

Amino acid composition of the Upper Ordovician, Silurian and Lower Devonian brachiopods and enclosing carbonate rocks of the western slope of the Northern and Polar Urals, Chernysheva and Chernov ridges, Northern Timan, 76- Labaganskaya and 2-Adakskaya holes was studied. The content of amino acids widely varies in shells (10-190 mg/g shell) and practically no change in the rocks (20-60 mg/g rock). It was established, that composition and quantity of amino acids in the shells of the Paleozoic brachiopods depend on the primary depositional environment, facies confinement, type of burial and the catagenetic processes of heating rocks of the Timan-North Urals basin. Secondary redistribution of host rock material and oxidizing conditions in the areas of natural exposures have also contributed to further destruction and modification of the organic substance of fossil organisms. It is shown that the increase in amino acid content in the shells is timed to three intervals of the Silurian section, which formation coincides with three eustatic transgressions.