Petrography and petrology of latest stage of Savalan volcanic rocks

In the latest stage of Savalan volcano formation, the Magmatism following the Subsidence of caldera Cause the formation of acidic and intermediate Dooms and viscose lava flows along fractures and within the margin of Caldera. mainly having composed of plagioclase, clinopyroxene, amphibole, biotite, potassic feldspar and quartz, Textural and mineralogy relations that are observed in studied microscopic sections, such as glomeroporphyric and glomerochristic occurrence of Mafic minerals as well as the presence of non equilibrium textures such ac sieve texture, bimodal composition of phenocherists of plagioclase, heterogenic composition of matrix, presence of basic micro pillows and enclaves in a acidic rocks, zenolites with reactional rims and also scattering and different trends observed in the geochemical reveals that fractionation, magma mixing and crustal contamination has been play important role in formation of this magmas. On the other hand The intermediate rocks of the region form do to of the mixing of basaltic magmas with fractionated sections , that have been contaminated with Crust during the ascent phase. Base on Petrographic and geochemical evidence presented hear, we show that the acidic rocks vastly in the area have a different origin than andesitid and trachy andesitid lavas. Likely that these rocks are the result of partial melting of the crust, while the replacement of basic magmas in crustal magma mixing phenomena has also been made between the two.