Abstract
Seventy-five Quaternary volcanoes in Guatemala have been studied by interpretation of aerial photographs and topographic maps. On the basis of the result, the distribution, structures, volcanic types, edifice development etc. of the volcanoes have been described. The volcanic region in Guatemala is divided into 7 blocks-Tajumulco, Santa Maria, Atitlan and Fuego, Amatitlan, Tecuamburro, Moyuta blocks, . In the Tajumulco block, most of the andesite volcanoes composed of lava flows 50-100 m thick near the boundary between Mexico and Guatemala are predominant with stratovolcanoes cut by steep scarps descending southward (probably fault scarps). In the Santa Maria block, the caldera volcanoes occupy in the northern part while the stratovolcanoes are predominant in the southern part. In the Atitlan block a large caldera volcano occupies in the extensive area with a large caldera and pyroclastic flow surfaces. In the Fuego block only stratovolcanoes stand. Older stratovolcanoes are in the northern area while the younger stratovolcanoes stand in the southern area. The blocking has been probably originated by segmentation of Cocos plates subducting from Pacific Ocean under Central America and by displacement of the Cayman transform fault.
