Vocabulary Terms

You should be able to define the following terms.
 

Anticline	Syncline	Antiform	Synform
overturned	limbs	recumbent	isoclinal
facing direction	anticlinoria	synclinoria	hinge (zone, point, line)
inflection point	attitude	axial plane	axial surface
axial trace	reclined	plunging	fold axis
cheveron fold	cuspate fold	interlimb angle	wavelength
amplitude	symmetrical	asymmetrical	concentric folds (parallel folds)
similar folds	Flexural-slip	Flexural-flow	drag folds
Key-stone grabens	Boudins	ptygmatic	cuspate-lobate

Concepts

You should be able to give short answers to the following questions:

1.) Given a cross-section with parallel dipping strata containing asymetric drag folds identify the location of axial surfaces and properly connect the layers into antiforms and synforms (see Figure 7.4. Also look at figure 7.54 A and C. Ignore Figure 7.54 B. It is trying to illustrate why this structure cannot be an antiform. However, it only serves to confuse most people.)

2.) On a fold identify: a) the hinge (point, zone, line), b) limbs, c) inflection points, d) trace of the axial plane.

3.) Classify a fold according to tightness (Fig. 7.38) and the Fundamental Fold Classification (Figure 7.46)

4.) Given the strike and dip of two opposing limbs of a fold determine the attitude of the fold using a steronet (strike and dip of the axial plane, and trend and plunge of the hinge line).

5.) Discuss the propagation of a concentric (parallel) fold. (Figure 7.43) (i.e., the room problem)

6.) Discuss the propagation of a similar fold (Figure 7.45) (i.e., thickening of hinges thinning of limbs)

7.) Discuss the variation in minor structures that can develop during flexural folding (drag folds, keystone grabens, boudins, thrust faults). Where on the fold they develop and why (e.g., Figure 7.52 and 7.56). You

8) Buckle Theory. Discuss the major variables that control the form of buckle folds. (%Shortening, Layer Thickness, Ductility Contrast, Layer Spacing) Don't just concentrate on the form of the equations, look at figures 7.68, 7.69, 7.70, and 7.72.