Thin shell of over-pressured viscous melt

Bubble Growth by Decompression 13.4.1. Thin shell of over-pressured viscous melt 

The growth of a bubble in a thin shell of over-pressured viscous melt (Fig. 13.1) is given by (Barclay et al., 1995) 

Assuming perfect gas law and isothermal conditions, the internal gas pressure (Pg) and the radius of the bubble (/ ) are related to the 

Assuming constant density of the melt shell, the constant mass of the melt shell gives the following relationship  

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