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2.1.2 Variation in fold plunge direction of sinusoidal folds 2.1.2b  

This sequence shows the affect of varying the fold plunges direction for a set of open sinusoidal folds in a 200 m thick layer, with fold axes plunging at 60°.

Notice the variations in field strength between hinges and limbs in both the gravity and magnetic images, the assymmetry between limbs in folds which are not plunging due north or south, and the marked differences between the north and south plunging magnetic images.

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Link	Block	Gravity	Magnetics
Folds plunging to 000 (North)	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	Notice the strong asymmetry of the magnetic anomaly in north-south sections, and the asymmetry between the anticlines in the north and the synclines in the south.
Folds plunging to 030	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	Notice the asymmetry of the magnetic anomaly between north-east and south-west facing limbs.
Folds plunging to 060	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
Folds plunging to 090	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
Folds plunging to 120	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
Folds plunging to 150	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
Folds plunging to 180	LOAD JPEG IMAGE	LOAD JPEG IMAGE	LOAD JPEG IMAGE
	Notice the symmetry of the magnetic anomaly in north-south sections, but the asymmetry between the anticlines in the north and the synclines in the south for the gravity but not magnetic images.

Key	Survey Parameters	Scale
layer r = 1 k = 10-2 background r = 0 k = 0 image width 10,000 m	Inclination -50° Intensity 50,000 Flight height 80 m	max min

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