An illustrated exploration of how Earth's surface changes over time.

Folds and Faults provides an illustrated overview of two significant topics in geology: folds and faults. Understanding folds and faults helps to explain how mountains form, how layers of rock change shape over time, and the underlying cause of earthquakes.
This app contains illustrations, animations, and photos by Dennis Tasa as well as annotated photos by Michael Collier and Ed Tarbuck. Animations show how folds and faults change the position and angle of rock layers. Illustrations and annotated photographs help to illustrate these concepts and aid in the identification of folds and faults in the field.


Overturned Folds
Normal Faults
Reverse Faults
Thrust Faults
Strike-slip Faults

What’s New

Version 2.0

This app has been updated by Apple to use the latest Apple signing certificate.

Universal app now supports iPhone and iPad.

Ratings and Reviews

5.0 out of 5
1 Rating

1 Rating

SF Presidio ,

Difficult Concepts Demystified!

Folds and faults are a 3D concept over Deep Time that is beyond the limits of a 2D textbook. Now you can carry a set of clear explanations and demonstrations into the field. Combine this with other Tama apps and Geology becomes a dynamic subject!

rutabage ,

TASA apps Folds and Faults and Geotimescale fail to open

TASA apps Folds and Faults and geotimescale fail to activate on my iTouch 4 using Operating sytstem iOS5, October 16, 2011.

Developer Response ,

Please upgrade to the latest version.

App Privacy

The developer, Danny Pilkenton, indicated that the app’s privacy practices may include handling of data as described below.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More


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