Lava is made of the elements silicon, oxygen, aluminum, iron, magnesium, calcium, sodium, potassium, phosphorus, and titanium (plus other elements in very small concentrations. A lava flow can move as far as 4 km from their source and have a thickness of 10 m if it has low silica content and low viscosities. These flows can move at rates of several km per hour. Lava flows that have more silica can move as far as 1.3 km from their source and have a thickness of 100 m and it travels at rates of a few hundred m per hour. If lava is traveling underground in lava tubes it can travel much farther.
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