lava domes

Lava domes are rounded, mound-shaped structures formed when thick, viscous lava erupts slowly from a volcano's vent. Because the lava is sticky, it doesn't flow far but instead piles up near the vent, creating a dome. Over time, the dome can grow larger or sometimes collapse, causing ash and volcanic gases to be expelled. Lava domes are common in some volcanoes and can indicate ongoing activity or potential for explosive eruptions. Their shape results from the balance between the lava’s high viscosity and the pressure from magma below.