1. FACULTY OF ENGINEERING TECHNOLOGY & RESEARCH
CIVIL ENGINEERING DEPARTMENT
STRUCTURAL GEOLOGY
Prepared by
Patel Milin
Patel Mohammed
Patel Akash
Patel Paresh
Guided by:
Prof. I.I. Chisty

2. Structural Geology
Structural geology is the study of rocks deformed by stress and strain
This involves trying to understand stress and strain forces to find solution of its pre-deformed state

3. When working in the field, Strike and Dip measurements are used to determine the orientation of rock units and other features
Strike – The compass direction of a line at the intersection of a geologic plane and a horizontal plane (water line)
Dip – The angle between the inclined plane and horizontal, perpendicular to strike

4. Folds, faults, and unconformities are the three main features that structural geologists examine
Folds occur when originally horizontal rock units deform under compressive forces. Common types of folds are anticlines and synclines.

5. • For every fold there is a fold axis, which is in the axial plane
Fold Terminology
Limb
Axis of Fold
Axial Plane
Crest
Trough
Plunge

6. • Some folds may plunge, these are called plunging folds
Plunging anticlines and synclines have
complex surface expressions

7. Types of Folds I. Based on Bending. 1. Anticlines 3. Antiform. 2
Types of Folds I. Based on Bending 1. Anticlines Antiform 2. Synclines Synform

8. II. Based on Position of Axial Plane 1. Symmetrical folds 2
II. Based on Position of Axial Plane 1. Symmetrical folds Asymmetrical folds 3.Overturned Folds 4. Recumbent Folds

11. Reverse – Hanging wall moves up relative to the footwall, caused by compression (shortening)

12. Faults are breaks in rock units were movement has occurred
Faults are breaks in rock units were movement has occurred. There are three major types of faults
Normal – Hanging wall (top surface) moves down relative to the footwall (bottom surface), caused by tension (extension)

13. Strike-Slip – Movement along the fault is horizontal, parallel to the strike of the fault plane. If, standing on one side of the fault, the block on the other side is displaced to the right, the fault is termed right-lateral. If the block on the other side is displaced to the left, the fault is termed left lateral
Is this fault right-lateral
or left-lateral?
Left-lateral

14. Unconformities are surfaces where erosion has occurred and represent gaps in the geologic record. There are three types of unconformities
Angular Unconformity – An unconformity in which the upper and lower layers are not parallel
Disconformity – An unconformity in which the upper and lower layers are horizontal
Nonconformity – An unconformity in which the upper layers overlie metamorphic or igneous rocks

15. References
Geology by R S Khurmi
Geology by Parbin Singh