Visible/Near-Infrared Spectra of Experimentally Shocked Plagioclase Feldspars

Introduction: Minerals subjected to high shock pressures exhibit structural changes with increasing pressure (e.g., fractures, deformations, formation of diaplectic glass, and complete melting [1-6]). Petrologic and thermal infrared spectroscopic studies have shown that diaplectic glass (maskelynite) formation in feldspars occurs between ~25-45 GPa, while significant melting occurs above ~45 GPa [712]. Past studies of visible/near-infrared spectra of shocked plagioclase feldspars demonstrated few variations in spectral features with pressure except for a decrease in the absorption feature near 1250 nm and an overall decrease in albedo [13-17]. We report new visible/near-infrared spectra of albiteand anorthiterich rocks experimentally shocked from 17-56 GPa.