Composite volcanoes are tall volcanoes with steep sides and thick, sticky lava. According to the book, the author said that the composite volcano in a strict sense refers to those volcanoes which have mixture of lava, but not in a simple layered sequence. In the Youtube video, composite volcano is high on gas. They eruptions with pyroclastic flow. Their pyroclastic ash and molten lava contain layers. For example, Mount St. Helens is an active composite in America which erupted in 1980 which kill 57 people.
