Geochemiczny zapis diagenezy szczątków kostnych z Jaskini Deszczowej (Wyżyna Częstochowska)

Abstract

Geochemical record of diagenesis of bone remains fromDeszczowaCave (Czêstochowa Upland).A b s t r a c t. The paper presents results of geochemical analysis of vertebrate bone remains from Deszczowa Cave. The cave is an archaeological and palaeontological site of Upper Pleistocene and Holocene sediments, located in Kroczyce Rocks, in middle part of the Polish Jura (Kraków–Czêstochowa Upland). The cave filling is composed of eleven layers (I–XI) interbedded with six culture horizons. The analyses covered bones from layers III–X were and comprised determinations of chemical and mineral composition of these remains and mineral precipitates at their surface. The obtained results made it possible to reconstruct diagenesis of bone remains. Four distinctive diagenesis types were recognized: (1) diagenesis under low pH and low Eh conditions; with solution of bone apatite and precipitation of manganese-barium oxides; connected with high content of organic substances in sediment; found in layers III, IV and V; (2) diagenesis under low pH and high Eh conditions; with Mn and Fe substitution in bone apatite, disintegration of collagen and mineralization with iron and manganese oxides, connected with infiltration of acidic waters; found in layers IV and VI; (3) diagenesis under high pH and low Eh conditions; with calcite mineralization, connected with stagnation or slow flow of karstic waters; found in layer VII; and (4) diagenesis under high pH and high Eh conditions; with calcite and goethite mineralization, connected with loess sediment or rapid flow of karstic waters; found in VII, VIII, IX and X.