Page 300 - Laboratory Manual in Physical Geology

FOLDED GEOLOGIC STRUCTURES (Ductile Deformation)

Axial plane Axial plane
axis asymmetric (steeper
(blue) Most anticlines are (blue) axis
on one limb than the
Limb other)
Limb
Limb Limb
Most synclines are
asymmetric (steeper Horizontal
Horizontal on one limb than the fold axis
fold axis other)

40
40
40
40

Older Younger Older Younger

A. SYNCLINE B. ANTICLINE

Axial plane Axial plane
(blue) (blue)

axis
Plunging
axis fold axis
Plunging
fold axis

45
45
45
45

Younger
Younger Older

Older

C. PLUNGING SYNCLINE D. PLUNGING ANTICLINE

FIGURE 10.8 Folds (ductile deformation) in block diagrams and geologic maps. Note how and where symbols from FIGURE 10.5
are used on the geologic maps.

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