THE DIFFERENCE BETWEEN BASALT VOLCANOES AND COMPOSITE VOLCANOES OF UGANDA

Today i based my research on finding the difference between basalt volcanoes and composite volcanoes of Uganda

Unlike composite volcanoes, Basalt domes are generally low and broad based sometimes extending to a diameter of 21km like for the case of Nyamulangira (also known as virunga Range or Mufumbiro Range)

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Basalt domes are formed from solidification of basic magma (lava) which flows a long distance before solidification to a not so high mountain.
The magma that forms Basalt domes like Nyamulangira is ejected through several or multiple fissures resulting into abroad based volcano.
Basalt domes are associated with a wide or large ,shallow, steep sided sunken crater which when filled with rain water forms a large crater lake on the top for example on Mt.Nyamulangira / Mufumbiro ranges.

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The process of formation of Basalt domes is as explosive as that formed from acidic magma. Examples of Basalt domes are Mufumbiro ranges or Nyamulangira volcano in kisoro aiong the Uganda-Congo-Rwanda border .

NB.Nyamulangira is one of agroup of 8 major volcanoes opn the Uganda –Zaire frontier, known as the virunga Range or mufumbiro Range. In this range there are also several small cones and craters.all the main volcanoes with the exception of Nyamulangira are composite cones.Nyamulangira rises 1500m above its base to a maximum height of 3056m. its 300 lower than its neighbors and has a large basal diameter of 21km. On top is a steep walled sunken crater over 2km wide and 75m deep. The crater formed by the subsidence of the volcano summit.

Whereas composite volcanoes are usually large volcanic cones with fairly steep slopes made up of alternating layers of ash and lava formed in phases where each layer represents a phase of erupt ion.

Composite volcanoes like Sabino,Gahinga, in kisoro (it has a secondary cone that developed on the side of Muhavura)
have parasitic or secondary cones on their sides as a result of either magma solidification in the central vent such that with secondary eruption , magma forces its way out trough a secondary vent created on the sides.
Composite cones like Sabino, Gahinga in kisoro were formed by acidic magma that does not take long to
solidify hence forming steeply sided mountains.

Formation of composite cones like Gahinga in kisoro is violent and explosive due to gaseous content in the magma.

Composite volcanoes are associated with a funnel shaped crater on the top which is filled by rain water to form a crater lake.