stress and it types are explained with figures and video

1. Department Of Earth & Environmental
Sciences
Structural Geology
December 3, 2015
Presentation Topic:- Stress and its Types
Presenters:- Ahsan khan

2. Stress and Types of
Stress

3. Stress
O Stress is conventionally defined as a force
acting on some area.
Fig 1

4. O Figure 1. Stress is defined as a force (F) acting on
some area (A).
O Figure 1 illustrates a force, F, acting on area A. In
the form of an equation this becomes
O where s is stress. Newton's first and second laws
of motion provide key ingredients for an
understanding of force, the principal parameter in
Equation (1).

5. Types of Stress
O Compressional Stress
O Tensional Stress
O Shear Stress

6. Compressional Stress
O causes the rocks to push or squeeze
against one another.
O can cause either horizontal or vertical
orientation,

7. Compressional Stress
O Compression causes reverse faults.

8. Tensional Stress
O Tension is the opposite of compression,.
O tension forces the rocks to pull apart,
O A rock that has experienced such type of
stress tends to be narrower and elongated
than its original shape.

10. Tensional Stress
O Tensional stress produces normal faults.

11. Shear Stress
O Forces from opposite direction, In which
forces run parallel to each other.
O The scale of shear stress can vary from
few cm to hundreds of meters.

12. Shear Stress
O Shear stress produces strike-slip fault.

13. Stress in Plate Tectonics
O Plate movement generates stress in the
rocks at plate boundaries.
O At converging plate boundaries rocks are
squeezed (compression),
O At diverging plate boundaries they are
stretched (tension or extension),