Algoman orogeny geophysical measurements on the greenstone belts in Canada, suggest the metavolcanic and metasedimentary rocks of the belts project downward at least a few kilometers. The action of metamorphism on the border between granite and gneiss bodies produces a succession of metamorphosed volcanic and sedimentary rocks called greenstone belts. Most Archean volcanic rocks are concentrated within greenstone belts; the green color comes from minerals, such as chlorite, epidote and actinolite that formed during metamorphism. After metamorphism occurred, these rocks were folded and faulted into a system of mountains by the Algoman orogeny. The volcanic beds are thick. About the greenstone belt
San Rafael orogeny San Rafael orogeny The San Rafael orogeny was an orogeny that affected parts of western Argentina and Chile during the Late Paleozoic. The resulting orogenic belt has a NW-NNW curved form. The San Rafael orogeny might have been linked with the roughly contemporary Gondwanide orogeny of eastern Argentina. Parts of the Choiyoi Group sediments were deformed by the San Rafael orogeny. During the Neogene ancient faults related to the San Rafael orogeny conditioned the geometry of the blocks affected by the Andean orogeny. Some of the plutons of the Elqui-Limarí Batholith were emplaced a context of crustal thickening derivative of