One of the key reasons for Federation was to achieve a united defence force which could better protect Australia. Around the 1880s, the Australian colonies had become increasingly concerned over the close proximity of foreign powers.
Split and merge into it. Answered by The Community. Making the world better, one answer at a time. Dissolved gases trapped in the magma provides the force that causes magma to erupt to the surface. Magma is molten material before it reaches the surface and is lava.
The slow decay of radioactive particles such as uranium, thorium and potassium produces heat deep within the earthâs core.The heat is transferred or conducted to surrounding rocks (called the mantle) causing a proportion of these to melt and become magma.Convection within the mantle enables magma to move upwards to the earthâs surface.he heat is transferred or conducted to surrounding rocks (called the mantle) causing a proportion of these to melt and become magma. Convection within the mantle enables magma to move upwards to the earthâs surface.