HUGONIOT EQUATION OF STATE OF BASALT

Shock compression experiments on Kinosaki basalt using an in-material gauge were carried out in the interests of elucidation of planetesimal collisions in the early solar nebula. Hugoniot equation of state is n ecessary for estimating impact induced pressure. Hugoniot of Kinosaki basalt is also useful to analyze previous impact disruption results. U sing in-material pressure gauge the shock pressure profile and shock w ave velocity (U-s) is measured to establish continuous Hugoniot equati on of state in the range 1-45 GPa. Although no substantial step was de tected in the shock pressure profiles, Hugoniot elastic limit (HEL) wa s identified at 5 GPa based on the U-s-u(p) relationship where u(p) is the particle velocity and is calculated by the impedance matching met hod. The shock profile showed long rise time and no substantial step a t HEL. These features can be explained by the constitution of multigra ined basalt. (C) 1997 Published by Elsevier Science Ltd. All rights re served.