Development of convection in the MHD simulation of the idealized oxygen shell run on a 512³ grid. The panels show fluctuations in pseudo-entropy (A = p/ρ^γ) in the z = 0 plane at different times, as indicated by the insets. The entropy generated by the heat source at the base of the box (see Fig. 1) is mixed throughout the initially adiabatic layer by turbulent convection. This process slowly increases the entropy content of the convection zone in time. The broad stripe of negative entropy fluctuation visible in the upper half of the domain at early times is due the thermal expansion of the convective layer. The turbulent flows also excite IGWs at the upper convective boundary (lower center panel) which then propagate in the subadiabatic layer.