DYNAMIC ANALYSIS

interprets stresses to describe the forces from which they were derived and the relationship between stress and strain

PERCENT LENGTHENING/EXTENSION (e)

REVIEW

DESCRIPTIVE ANALYSIS

is the reconstruction of movements that take place during the formation and deformation of rocks

KINEMATIC ANALYSIS

DEFINITIONS
 
 

READINGS CH.3 CH.4

LECTURE
 
 

STRAIN

 Non-rigid body rotation is particularly important when we deal with the concept of strain. Strain is internal deformation. Trying to describe strain mathematically can be very difficult. It is often common to at least initially assume that the type of strain is very simple, i.e. it is the same throughout, that it is uniform throughout the body. And if we find that this assumption is not the most appropriate we can break up the body we are studying into smaller parts inside which the assumption holds true.

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LINEAR STRAIN

 Quantification of strain is important because it can predict other geological processes. For example, using a homogeneous deformation model, if whole lithospheric thinning exceeds 300% theoretically by some calculations, volcanism may occur.
 
 

How do we quantify extension in rifted margins?

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 How are % lengthening, extension, and stretch factor all related?

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ROTATIONAL STRAIN
 
 

Dynamic Analysis- Discussion
 
 

In Geology you will always hear of the use of stress instead of force Why?

 In the earth what forces are responsible for bending rocks? faulting rocks? Why can a rock hammer break a rock but buildings constructed on basement rock not break the underlying rock?