FAST-CHANGING DYNAMIC AND PERCOLATION PROCESSES IN CRUSHED ROCKS MONITORED WITH ELECTRIC RESISTIVITY MEASUREMENTS

摘要

The paper presents application of a new method for studying the crushed rocks by means of automatic electric resistivity recording system. The prototype of press with the so-called percolation bomb designed for experiments on crushed rocks is described. The electrodes of the automatic recording system for resistivity measurements are installed within this bomb. Samples of crushed calcium carbonate rocks of various grain size were examined. Analysing the course of resistivity versus load it was possible to distinguish the following types of events: avalanche, stepwise, and impulse-type events of varying amplitudes and durations (from micro- to macro-impulses). The applied method expands the scope and improves the accuracy and reliability of studies of percolation and dynamic processes in rocks; the results corroborate a threshold nature of these processes. The obtained results can be helpful for analysis of the observed dynamic events as monitored by resistivity measurement at water dams. Further experiments may be also helpful in studies of precursory phenomena prior to earthquakes.