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CONVERGENT BOUNDARIES And Mountains Building Orogenesis : the processes that produce a mountain belt. It includes: 1. Folding 2. Thrust faulting 3. Metamorphism 4. Igneous activity (Plutons (batholith) and Volcanism). Appalachian Mountains. Ural Mountains.
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CONVERGENT BOUNDARIES And Mountains Building Orogenesis: the processes that produce a mountain belt. It includes: 1. Folding 2. Thrust faulting 3. Metamorphism 4. Igneous activity (Plutons (batholith) and Volcanism)
Several hypotheses have been proposed for the formations of Earth’s mountain belts:
at convergent plates • at Continental Plates Collisions • due to Continental accretion • 4. Fault-block mountains
Convergent boundary of two oceanic plates. Creates an ________ and a _____. Example: _____ island arc trench Japan
Convergent Plate Boundaries • Older portions of oceanic plates are returned to the mantle in these destructive plate margins • Surface expression of the descending plate is an deep ocean trench • Also calledsubduction zones • Average angle of subduction = 45 • 1000’s km long, 8-12km deep, 50-100km wide.
Convergent boundary of an oceanic plate and a continental plate. Forms a _______ mountain range and a ______. Examples: _______ or ______ Mts volcanic trench Andes Cascades
Aforearc=forarc =arc-trench gap: adepressionin thesea floorlocated between asubduction zoneand an associatedvolcanic arc. It is typically filled withsedimentsfrom the adjacent landmass and the island arc in addition to trappedoceanic crustalmaterial.
Convergent boundary of two continental plates. Forms a ______ mountain range. Examples: ___________, Alps, ______________ Himalayas folded Appalachians