Studies of thermal and radiation effects on water-rock systems related to envisaged isolation of high level radioactive wastes in crystalline formations of the Ukrainian shield (Ukraine)

In this work there are presented the general data on the study of thermal and radiation effects in minerals separated from rocks of the Ukrainian shield. These minerals (quartz, feldspar, amphiboles, apatite, biotite, kaolinite, etc.), exposed by doses 104, 106, 108 Gy by Co60 source, were studied by a complex of physical methods. Special attention was given to the study of radiation defects formation (electron-hole paramagnetic centres, OH- groups destruction, changes in a charge state of ions) in a mineral structure. The mentioned radiation defects were used in the extrapolation method. The connection between structural peculiarities of minerals (containing uranium and thorium) and processes of their metamyctization are considered. It is demonstrated that the minerals, which have large channels or interlayer spaces in their structure, as a rule, are not metamyct. Using the spectroscopic methods of the extrapolation it is shown that the crystalline massifs, which do not have detectable amounts of hydroxyl containing minerals (biotite, amphibole, etc.) and ions Fe2-, are perspective for long-lived radioactive wastes (RAW) dumping. As it follows from obtained results, the rocks, containing minerals with OH- groups and gas-liquid inclusions, should be considered as the 'mineral-water' system. (author)