Experimental study on high-temperature rheology of hot-pressed mafic granulite

The earth's internal dynamic processes are closely related to the rheological behavior of its internal constituent minerals under high temperature and high pressure conditions. Feldspar and pyroxene are the main constituent minerals in granulite in the continental lower crust. High-temperature experimental research on them is one of the main ways to understand the rheology of the continental lower crust. This experiment uses the Paterson high temperature and high pressure rheology device, at a temperature of 1273K-1423K and a strain rate of 6×10-6 s ^-2×10-5s^-1, to test the hot-pressed feldspar and pyroxene aggregates with and without water respectively. Creep experiments were carried out under added water conditions to determine the rheological parameters of the two-phase aggregate under different water conditions. By collecting infrared spectra and microscopic pictures of the two-phase aggregate of hot-pressed feldspar and pyroxene, the water content in the samples before and after deformation was calculated and its microstructural characteristics were analyzed. The Q value of the sample without adding water is 797.87±184.7 KJ/mol, and the n value is about 3. The Q value of the water-added sample is 472.57±96.29KJ/mol. From 1273K to 1373K, the n value is about 2. At 1373K, the n value is about 4. This shows that water has a significant weakening effect on rocks.