Plagioclase breakdown as an indicator for shock conditions of meteorites

摘要: The collision history of asteroids in the early Solar System is difficult to reconstruct. A study plagioclase breakdown using X-ray diffraction measurements under increasing pressures and temperatures suggests that peak collisions formed shocked meteorites have been overestimated. Shocked were when their parent body underwent shock metamorphism often contain mineral either an amorphous form or its high-pressure phase. can be constrained by shock-recovery experiments determine amorphization plagioclase1,2,3. However, these unrealistically low timescales much shorter than those natural events. Here we present situ two kinds feldspar conditions temperatures. We find pressure decreases with temperature, suggesting previous studies overestimated this parameter1,2,3. also found jadeite forms first from plagioclase, whereas nucleation other minerals such as stishovite garnet significantly delayed. occurrence do not stishovite4,5,6,7,8 therefore explained a result crystallization kinetics. conclude constrain pressure–temperature–time events, thus help reconstruct collisional System.