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3.7 Fold Interference Patterns

This sequence duplicates the well known fold interference patterns of Ramsay, although see Theissen & Means and Theissen for a more complete scheme.
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Link	Block	Gravity	Magnetics	Magnetics	Magnetics at Pole	Magnetics at Pole 1VD
A	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	This is a type 1 pattern, also known as a dome and basin pattern.
B	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	This is a type 1 pattern, and is also a form of dome and basin pattern.
C	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	This is a type 0 pattern, where the two fold systems are completely parallel (and it is thus unlikely you would be able to distinguish the two phases of folding).
D	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	This is a type 1 (+2) pattern.
E	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	This is a type 1 (+2) pattern.
F	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	This is a type 3 pattern.
G	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	This is a type 2 pattern, also known as a mushroom pattern.
H	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	This is a type 2 pattern, also known as a mushroom pattern.
I	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	This is a type 3 pattern.

Key	Survey Specifications	Scales
blue layer r = 0 k = 0 yellow layer r = 1 k = 10-2 image width 10,000m	Inclination 50° or 90° Intensity 50,000 or 70,000 gamma Flying height 80m	max min max min

Ramsay, 1967, Folding and Fracturing of Rocks, MacGraw-Hill, p531.
Theissen & Means, Journal of Structural Geology, 2, pp311-316.
Theissen, 1986, Journal of Structural Geology, 8, pp563-573.

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