Textures and structures present in magmatic rocks represent the additive results of continuous activity from crystallization through post-solidification. Layered syenitic rocks from the Red Hill intrusive complex show deformed cumulate textures and structures that are used to determine the relative time sequence of their formation and development. Texture and structure formations are related to five phases of crystal-magma evolution: primary crystallization, early accumulation, intermediate accumulation, late accumulation, and post-solidification. Individual features are related to one of the phases and to the processes that were operating during the phase. By assembling all of the textures and structures into a relative order of appearance, it is possible to identify major whole-rock textural transformations. These grade from early-formed cumulate texture through tightly packed laminate, to hypidiomorphic-inequigranular, allotriomorphic-granular, and finally, recrystallized mosaic texture.

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