ICE ROCK POROUS MIXTURES - COMPACTION EXPERIMENTS AND INTERPRETATION

Compaction experiments on porous samples of granular ice and ice/rock mixtures were conducted at low temperature, primarily to obtain rheolo gical data useful in modeling the internal structure and evolution of icy satellites of the giant planets. The data may also be of interest for studying Earth's glaciers and the Martian polar caps. The samples tested were prepared from three types of ice: water, carbon dioxide an d ammonia; three types of rock components were also used in the sample s. The time-dependent compaction of samples a few centimeters in size was studied for a range of rock contents, pressures (2.2-17.7 MPa) and temperatures (140-261 K). An equation (16), giving the compaction rat e as a function of porosity, pressure, temperature and concentration o f the rock component was fitted to the observed results. The presence of rock fragments strongly inhibits the compaction process.