31. For example, porphyritic andesite will have large phenocrysts of plagioclase in a fine-grained matrix. 32. Most is strongly deformed, but least-deformed areas show a relict porphyritic to equigranular texture. 33. The porphyritic trachytes erupted at the summit of the shield and flowed towards the northeast and east. 34. "Porphyritic " textures develop when conditions during cooling of a magma change relatively quickly. 35. Porphyritic plagioclase andesite of the youngest unit underlies much of the southern and western portions of Meager.36. The surrounding loose rock was cleared away by the ice sheet leaving the hard porphyritic core behind. 37. Gneiss is the predominant rock with a few granite Porphyritic matrices occasionally occur in the rock formations. 38. Aphanites are commonly porphyritic , having large crystals embedded in the fine groundmass or inclusions are called phenocrysts. 39. The sequence has been divided into a lower pillowed tholeiitic unit and an upper porphyritic alkali basalt unit. 40. The hamlet of Bluestone is named after a granite boulder porphyritic crystals, which are no longer visible.
