The Nam Kar volcano range is composed of three volcanoes in a valley in Phu Son village, Quang Phu commune, Krong No district.
The main and highest scoria (M) cone is c.60m high, 220m in diameter, with a small crater c.20m deep on the summit at c.660m asl. Composed of beds of scoria of several cm in diameter, it is perfectly round and sharp.
A few tens of meters to the north, the smaller spatter (S1) cone (605m asl, height 24.2m) is composed of spatter, scoria and bombs c.10cm in diameter. The cone has no crater on top. Instead, several gas-escape, pipe-like structures appear in its road cutting section, resembling “tree molds”.
To the south, also a few tens of meters distant, the lowest lava (S2) crater (621m asl, height 22.4m) has a horse-shoe shape, which indicates where the lava was spewed out in several episodes, eventually forming a pahoehoe lava field c.4.75km2 in area.
The scoria and spatter cones are believed to have been formed earlier than the lava crater, at the beginning of the eruption, when the lava was still rich in gases and low in viscosity. The lava was erupted into the air together with gases, torn apart and cooled rapidly. It then fell and gathered together to form stacks of volcanic scoria. The eruption also contained volcanic bombs of various shapes and sizes, which have an outer shell of volcanic glass due to the rapid cooling. Later, the lava contained less gas and less viscosity hence spewed out to form a pahoehoe lava field.
Being well-conserved the volcanoes are clearly very young, less than 10,000 years old. This is a must-see destination for those who love to study and explore the typical geological and geomorphical value of Dak Nong UNESCO Global Geopark.