论文部分内容阅读
发生在寺巷口陨石冲击脉体的较大冷却速率 ( >1 0 0 0 0℃·s-1)使得橄榄石(α 相 )的高压多型γ相被保存了下来 ;冷却速率中等的和平河陨石冲击脉体 ( 1 0 0 0~ 2 0 0 0℃·s-1) ,γ相部分逆转为β相 ,但β相向α相的进一步逆转受阻 ,脉体保存了β相 ;冷却速率较慢的蒙巴喇陨石冲击脉体 ( <5 0 0℃·s-1) ,γ相几乎全部逆转为α相 .冲击脉体的热散失滞后于陨石母体冲击压缩阶段 ,发生在陨石母体崩解成碎块以后 .脉体的冷却速率制约了 (Mg ,Fe) 2 SiO4高压多型的逆向转变过程 .
The large cooling rate (> 10 0 ° C · s-1) of the meteorite impact pulse body at Sihekou meteorite causes the high-pressure polytype γ phase of olivine (α phase) to be preserved; the moderate cooling rate The river meteorite impacted the pulse body (100 ~ 2000 ° C-s-1), and the γ phase partially reversed to β phase, but the further reversal of β phase to α phase was blocked and the β phase was preserved in the pulse body. The cooling rate The slowly impacted Momabian body (<5 0 0 ℃ · s-1), the γ phase almost completely reversed to the α phase. The thermal dissipation of the impulse lag lags behind that of the meteorite matrix during the impact compression, which occurs when the meteorite matrix disintegrates After fragmentation, the rate of cooling of the pulse body constrained the reverse transformation of (Mg, Fe) 2 SiO 4 high-pressure polytype.