Compound volcanoes are volcanoes composed of more than two volcanic cones. It is a hill formed by the accumulation of volcanic ejecta around the vent. Due to the different nature, quantity and eruption mode of the ejecta, it has a variety of shapes and structures. [3]
A conical volcano with steep slopes, composed of lava and Volcaniclastic rock Interbedding composition. Its height can reach several kilometers, and its volume can reach many cubic kilometers. Near the top of the mountain, the slope can reach 30 ° or more, but near the bottom, the slope can be much flatter, so the slope of the composite volcano is concave. The interbedding of lava and volcaniclastic rock produces macroscopic bedding. Its name reflects this feature. [1] Beds and dikes often occur. These rock beds and dikes, together with the rock flow, have consolidated Volcanic cone And make the volcanic cone more resistant to denudation. Composite volcanoes are generally composed of more andesitic or silicoaluminal rocks. When composite volcanoes are active, quiet eruptions (erupting lava flows) alternate with more violent eruptions (ejecting pyroclasts). If the compound volcano is active or only slightly denuded, then there will be a crater or caldera on its top. Volcanic clastic rock cinder cones and accumulation domes often appear on its flanks. Compound volcanoes are steeper than shield volcanoes and contain more pyroclastic materials. They are like cinder cones, with steep slopes but larger volumes. Even in low latitudes, composite volcanoes are generally covered by snow fields and radiating glaciers because of their high altitude. Therefore, moraines and other glacial sediments can be interbedded with lava and pyroclastic rocks, such as the crater lake volcano in Oregon. Most composite volcanoes are volcanic cones. Compound volcanoes include: Shasta, Hood, Saint Helens and Rainier in the Cascade Mountains; Popocatepeter and Orizaba in Mexico; Mount Fuji in Japan; Vesuvius in Italy; Mayon volcano in the Philippines; Kotopakhi, Ecuador; Chichardin in Aleutian Islands and Mount Kilimanjaro in Tanzania. [2]
