**Each cycle punctuated by at least one granite forming event

(1) Erosion-filling in trough (geosyncline) Erosion of crustal highs

(2) Volcanism-Look up (m) miogeocline (E) Eugeocline

(3) Deformation-recrystallization

(4) Engulfment by partial melt Granite forming event

(Event on which age is assigned)

(5) Rising of Granitized mountain range

Partial melting-incomplete melting of rock some of the minerals melt

(function of temperature)

Partial Melt of Lithosphere produced Granite

Partial melt of Asthenosphere (upper mantle) produces Basalt

Accretion and Secular differentiation of North America (3 features)

1. striking analogy between the oldest rock complexes in the Heart of North America and rocks of island Arcs

2. progressive secular differentiation of Igneous and sedimentary rocks in successively formed geologic provinces from rocks typically oceanic in character to rocks more characteriestically continental

3. crudely zonal pattern of succesive major granite forming and related continent-forming events

"Oldest is in the middle"