Structural changes in amber due to uranium mineralization

0463518 - ÚSMH 2017 RIV GB eng J - Journal Article
Havelcová, Martina - Machovič, Vladimír - Mizera, Jiří - Sýkorová, Ivana - René, Miloš - Borecká, Lenka - Lapčák, L. - Bičáková, Olga - Janeček, O. - Dvořák, Z.
Structural changes in amber due to uranium mineralization.
Journal of Environmental Radioactivity. 158-159, JUL (2016), s. 89-101. ISSN 0265-931X. E-ISSN 1879-1700
R&D Projects: GA ČR(CZ) GA13-18482S
Grant - others:OPPK(XE) CZ.2.16/3.1.00/21538
Program: OPPK
Institutional support: RVO:67985891
Keywords : fossil resin * amber * uranium * radiolytic alteration * micro-FTIR * mapping * SEM/EDX
Subject RIV: DD - Geochemistry
Impact factor: 2.310, year: 2016

The presence of uranium, with a bulk mass fraction of about 1.5 wt% and radiolytic alterations are a feature of Cenomanian amber from Krizany, at the northeastern edge of the North Bohemian Cretaceous uranium ore district. Pores and microcracks in the amber were filled with a mineral admixture, mainly in the form of Zr-Y-REE enriched uraninite. As a result of radiolytic alterations due to the presence of uranium, structural changes were observed in the Krizany amber in comparison with a reference amber from Nove Straseci in central Bohemia; this was of similar age and botanical origin but did not contain elevated levels of uranium. Structural changes involved an increase in aromaticity due to dehydroaromatization of aliphatic cyclic hydrocarbons, loss of oxygen functional groups, an increase in the degree of polymerization, crosslinking of C-C bonds, formation of a three-dimensional hydrocarbon network in the bulk organic matrix, and carbonization of the organic matrix around the uraninite infill.
Permanent Link: http://hdl.handle.net/11104/0262694