Mount Ruang

About Mount Ruang

• It is a stratovolcano located in Indonesia’s North Sulawesi province.
• It is a 725-meter (2,400-foot) volcano.
• The summit of Ruang stands 10,932 feet above sea level, with a caldera that is about two miles wide.

What is a Stratovolcano?

• It is a tall, steep, and cone-shaped type of volcano.
• Unlike flat shield volcanoes, they have higher peaks.
• They are typically found above subduction zones, and they are often part of large volcanically active regions, such as the Ring of Fire that frames much of the Pacific Ocean.
• Strato Volcanoes comprise the largest percentage (~60%) of the Earth's individual volcanoes, and most are characterized by eruptions of andesite and dacite, lavas that are cooler and more viscous than basalt.
• These more viscous lavas allow gas pressures to build up to high levels. Therefore, these volcanoes often suffer explosive eruptions. 
• They are usually about half-half lava and pyroclastic material, and the layering of these products gives them their other common name of composite volcanoes.

At the peak, stratovolcanoes usually have a small crater. The crater may be filled with water or ice, or it may contain a volcanic dome during a period of relative inactivity.

Q1: What are Pyroclasts?

Pyroclasts (or "tephra') are any volcanic fragments that were hurled through the air by volcanic activity. A pyroclastic eruption is one in which the great majority of activity involves fountaining or explosions. A pyroclastic deposit is the resulting layer or pile of material that has fallen to the ground by one or many pyroclastic eruptions. A pyroclastic rock is the hardened, solidified, or compressed version of an originally loose pyroclastic deposit.

Source: Indonesia's Ruang mountain spews fiery lava thousands of feet into the night sky; tsunami alert raised