Consider a magma with bulk density ρ in a chamber of volume V undergoing a mass recharge rate Q i and eruption rate Q 0, as sketched in Fig. 1. Conservation of mass indicates that: where Q = Q i - Q 0 ...

In a surprising overturn, the lustrous, blue-white element osmium has beaten diamond in a test of compressibility. Not used much today, osmium has been incorporated into alloys for fountain-pen tips ...