Direct observation of degassing in decompressing basaltic magma reveals two timescales that determine whether an eruption is explosive or effusive. In low-viscosity melts, gas bubbles coalesce and recover spherical shapes within three seconds of deformation. In higher-viscosity magmas, recovery takes far longer — long enough that connected bubble pathways persist, creating permeable channels through which gas can escape before it builds to explosive pressures.
The eruption style of a volcano — whether it fountains gently or detonates — depends on whether gas can leave the magma faster than the magma rises. If bubbles coalesce quickly and recover their isolated spherical geometry, each bubble remains a sealed pocket of pressure. As the magma ascends and external pressure drops, those sealed pockets expand until fragmentation occurs — an explosion. But if the bubbles stay deformed and connected long enough to form a permeable network, gas bleeds out continuously, pressure never accumulates, and the eruption is effusive.
The three-second recovery time in basalt is therefore a critical threshold. It separates two regimes — sealed versus permeable — and the regime determines the eruption character. The viscosity of the magma sets the clock. Higher silica content, lower temperature, more crystals — any of these slows bubble relaxation, extending the window during which connected pathways exist.
The through-claim applies anywhere a system's behavior depends on whether a transient structure persists long enough to function. Bubble networks in magma, crack networks in fracturing rock, temporary alliances in competitive systems — the question is never just whether the structure forms, but whether it lasts long enough to change the outcome. The race between formation and relaxation determines whether the transient becomes consequential.