1) There are different types of folds that can be identified on a geologic map based on the attitude of their axial planes and the direction of dip of the strata. Synclines and anticlines can be distinguished by the direction strata dip and the age of the strata. 2) Folds should be described on a map by specifying the type of strata, the direction of the fold axis, any plunge direction, and whether it is symmetrical or not, plunging or not, and if it is a syncline, anticline, or monocline. 3) When writing a report for a geologic map, it is important to discuss the geomorphology, structure geology, topography

1. Section 1
Folds on geologic map
Edited by: Mostafa Abdel Azim Masoud
Demonstrator – Geology department- Faculty of Science

2. Synthesis of fold

3. Types of folds according to attitude of axial plane

7. Criteria of folds

8. Criteria of folds

9. Difference between syncline and anticline folds on map
1) Direction of strata dip
In anticlines the direction of strata around the
axis is away of the core and in syncline the
direction is toward the core.
2) The age of strata
In anticlines the oldest strata are in the core and
the youngest and vice versa in synclines.
3)Direction of plunge
In plunging anticline folds, the plunge is in the
same direction of closure, and in synclines, the
plunge in opposite direction of closure.

10. How to describe the folds on map ?
1-Type of strata consisting the fold.
2-Direction of fold (fold axis).
3-Direction of plunge (in case of plunging fold).
4-Type of fold:
*Symmetrical or non symmetrical.
*Plunging or non-plunging.
*Syncline , anticline, monocline.

11. How do you know the direction of river on map
• 1) V-shape
• 2) Alluvial deposits
• 3) Values of contour lines

12. Report of map
To write a report for a geologic map, you should keep in mind three
aspects which are :
1) Geomorphology: such as volcanic activity, erosion, transgression,
regression, general slope ………..etc.
2) Structure geology : such as folds, faults, domes, basins,
unconformities…..etc.
3) Topography: mountains, hills, plateau……etc.
4) History of map.

14. Double plunging folds

15. Double plunging anticline

16. Map 2

19. faults