Objective• Students will be able to identify and describe two types of rock deformation and explain the difference between them.• Students will be able to demonstrate three types of faults by acting them out using their backpack.
The Results of Stress• High pressure and temperatures caused by stress in the crust generally deform rocks.• When stress is applied slowly, the deformed rock will return to its original shape.• In extreme stress, rock becomes so deformed it may bend, tilt or break.
Folding• When rocks respond to stress by becoming permanently deformed without breaking it is called folding. – Folds vary in size – There are 3 general types of folds.
3 General Types of Folds • Anticline: Upfolding or arching in which the oldest layer is in the center of the of the fold k yer of rocOldest la
Faulting• When rocks break due to stress instead of fold. – Joint: no movement in the rocks along either side of a break. – Fault: when rocks do move – Fault plane: surface of a fault where any motion occurs – Hanging wall: rock above the fault plane of a nonvertical fault – Footwall: rock below the fault plane of a nonvertical fault
3 Types of faults• Normal fault: hanging wall moves down relative to the footwall along divergent boundary• Reverse fault: compression causes the hanging wall to move up relative to the footwall• Thrust fault: fault plane is a low angle or nearly horizontal & hanging wall is pushed up over rock• Strike-slip fault: rock on either side of the fault plane slides horizontally at transform boundaries
Mountain Formation• Mountain Range: a group of adjacent mountains with the same general shape and structure.Mount Everest Himalaya Mountains
Mountain Formation• Mountain System: a group of adjacent mountain ranges.Great Smoky Mountains Green Mountains Appalachian Mountains
Mountain Formation • Mountain Belts: the largest mountain system are part of two still larger systems. Circum-Pacific mountain beltEurasian- Melanesian mountain belt
Plate Tectonics and Mountains• Both circum-Pacific mountain belt and the Eurasian- Melanesian mountain belt are located along convergent plate boundaries.• Evidence that most mountains are formed from plate collisions.• Ding Ding: Convergent Plate Boundaries build mountains!!!
Collision between Continental and Oceanic Crust• What do we know happens when continental and oceanic crust collide?• What do we know happens when crust overlap each other? What can happen?• This will causelarge scale deformation.ContinentalVolcanic Arcs!!!
Collision between Continental and Oceanic Crust
Collision between Oceanic and Oceanic Crust• One plate usually submerges below the other and will cause a volcanic island arc. Mariana Island in the North Pacific Ocean
Review• What is folding? What type of deformation?Rock deformed without breaking...Ductile• Name three folds...Anticline, Syncline, Monocline• What is faulting? What type of deformation?Rock deformed by breaking...Brittle• Name four faults...Normal, Reverse, thrust, and Strike-Slip 23
Review• What boundary are most mountains formed?Convergent Plate Boundaries• What boundary do strike-slip faults occur?Transform Fault Boundaries• What convergent plate boundary are the tallest mountains formed?Continental-Continental Convergent Plate Boundaries 24