Temperature dependences of hydrous species in feldspars

摘要: Feldspars are abundant in the crust of Earth. Multiple hydrogen species such as OH, H2O and NH4+ can occur structure feldspars. Hydrogen play a critical role influencing some properties host feldspars crust, including mechanical strength, electrical property evolution crustal fluids. Knowledge hydrous to date has been mostly derived from spectroscopic studies at ambient temperature. However, speciation sites high temperatures may not be quenchable. Here, we investigated temperature dependences several typical components (e.g., type IIa IIb OH I H2O) by measuring situ FTIR spectra elevated up 800 °C. We found that demonstrated different behaviors temperatures. With increasing temperature, redistributes on various anorthoclase structure. Additionally, O–H vibration frequencies increase for types they decrease with In contrast which drastically dehydrates during heating process, show negligible loss; however, bulk integral absorption coefficients These results have implications understanding non-ambient temperatures, only under geologic conditions but also cold planetary surface conditions.