Fissure eruption
The magma overflows along the narrow and long cracks, which is called fissure eruption. This kind of crater is not circular, but appears as a fracture zone tens of kilometers long, or a series of craters arranged in a beaded shape. Fractured eruptions are dominated by basic magma with low viscosity and high fluidity, which mostly overflow slowly and flow along the ground to form lava blankets. In the early geological history, the crust was relatively thin, dominated by fissure eruptions.