" Lava is Molten rock on the surface of the earth released from a volcano. When molten rock cools down, it solidifies and forms rocks and minerals.
Basalt underlies more of Earth's surface than any other rock type.
Most areas within Earth's ocean basins are underlain by basalt. Although basalt is much less common on continents, lava flows and flood basalts underlie several percent of Earth's land surface. "