ИСТИНА

Experiments with tuff samples in close and open system from borehole on hillside of volcano Baransky (Kuril Islands) have been performed at high pressure (P) and temperature (T). Sampling depth varied from young superficial sediment layers to deeply hydrothermally altered layers (up to 1500 m). The main aim of the studies was investigation of evolution of pore space during long sedimentation and further subduction in deep interior. It was found that the samples collected nearby surface were nonlinear enlarged with increasing temperature (up to 300 0 C) under isobaric conditions (P = 0.7 GPa) whereas deep samples have linear expansion. Analyze of this results and additional studies of pore space showed that the nature of this process is found in deformation and reconstruction of rock framework.