lec1 ppt

Overview of Structural Geology

(Chapter 1 in D &R)


Why is it important?
- fundamental discipline in Earth Sciences- “the stud
of the architecture of the Earth’s crust”
- geometry is key to many ES applications (oil, mini

Our goals: (1) to learn how to make structural observation
present them to others;
(2) to interpret the processes that led to the “fin
“product”- the geologic observations.


Primary vs. secondary structures.

Primary: depositional contacts, cross-bedding, ripple mar
Ropy textures in lavas, mud-cracks;


Secondary: these are the real structures we’re after- and
are due to rock regional deformation. Examples:
Folds, faults, shear zones, etc.
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Structural analysis:

1. Descriptive analysis
2. Kinematic analysis- deformational movements- transla
rotations,distorsions, etc.
3. Dynamic analysis - interprets the forces and stresses
associated to deformations.


Scale of analysis.


Geologic time scale

4.5 Ga old, structures can be very old. Rates of processes


Kinematic reconstruction:
Rotations, translations, dilations, distortions

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Dynamic analysis:
- physical models (experimental)
- mathematical models (theoretical)

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Read Chapter 1 in DR

Next: Large scale deformations
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