Russian Journal of Earth Sciences
Vol. 5, No. 4, August 2003
A new line in investigation of physical properties of rocks
and minerals at high pressures and temperatures
S. M. Kireenkova, and G. A. Efimova
Abstract
The decisive problems at present in the experimental investigation of rocks and minerals
at high pressures and temperatures are the problems of studying processes which are
going on
inside using various physical methods. The most important avenue of experiments is
investigation of changes of physical properties of the rocks and minerals at high
pressures and
temperatures.
The majority of papers in this line give a quantitative assessment of the physical
characteristics, establish factors these characteristics depend on, and major patterns
of their variation at high pressure and temperature parameters.
Aside of this, abnormal manifestations of physical properties of the rocks were revealed
prior
to destruction, in the dehydration processes and in the phase changes
[Levykin, 1991;
Parkhomenko, 2000;
Volarovich et al., 1974, 1975, 1979a].
These investigations suggested that the abnormal changes of the
rock physical parameters at high pressures and temperatures indicate to one or another
process
and are connected with the microstructure changes in the rocks and minerals. With
allowance for
the main direction, problems were set before the laboratory working on simulation
and analysis
of processes in the seismic zones to investigate a physical nature of the earthquake
preparation processes
and the attendant forerunners, at different scale levels, on the basis of experimental
investigations of the rock and mineral properties and their variation at high pressures
and
temperatures.
The neutron diffraction method, as the method possessing optimum capabilities among
other microstructure methods of investigation of the matter, was selected as a physical
investigation method.
Calcite, that have received the most study at high pressure and temperature parameters
and which
is prevailing in the Earth, was selected as the first object of investigation.