Rapid ascent through a diatreme in this process can create a "neck.
The fissure type of this process tends to form spatter ramparts. A namesake column due to this process results from volatiles, such as water, forming bubbles. Rapid ascent through a diatreme in this process can create a "neck." The magnitude of this process is measured on the VEI scale. When the product of this process is majorly andesitic, it forms a discontinuous or blocky surface; that product of this process has its viscosity affected by temperature and silica and gas content. Types of this process include Hawaiian, Strombolian, and Plinian. This process involves structures that can come in shield, strato- and cinder cone varieties. For 10 points, what is this process in which molten rock is spewed out on the surface of the Earth?
The fissure type of this process tends to form spatter ramparts.
volcanic eruptions [or volcanism; or fissure eruptions; prompt on obvious equivalents, such as lava coming out of volcanos onto the surface of the Earth]