Metamorphic response characteristics of yellow sandstone after heat treatment under 800-1250 °C

Coal, geothermal and nuclear energy have always gained attention as important factors affecting the environment. In order to understand the impact of the high temperature generated before and after the development and utilization of these resources on the properties of the surrounding rock, a high-temperature thermal damage metamorphism mechanism test study was conducted for the yellow sandstone, which was widely distributed in the formation. The yellow sandstone was heated under 800-1250 degrees C. From the changes in thermal conductivity, longitudinal wave velocity (V-P) and intensity, combined with scanning electron microscope (SEM) images, and magnetic susceptibility, the yellow sandstone showed different degrees of changes at high temperatures. The results showed that the main influence on lithology is the metamorphism caused by high temperatures after 800 degrees C. Under different temperatures, the changes ratio of primary minerals and melts is different, leading to inconsistent variation in the characteristic properties. This phenomenon was most prominent as the temperature was in the range of 1000-1200 degrees C. Under the studied temperature range, the performance of yellow sandstone gradually decreased, and the thermal damage and degree of metamorphism increased gradually.

Automated summary

This study conducted a test on the changes of yellow sandstone under high temperature, and found that high temperature has a significant impact on the properties of the rock, mainly manifested as metamorphism after 800 degrees Celsius. Under different temperatures, the changes ratio of primary minerals and melts vary, resulting in inconsistent variation in the characteristic properties.