324 SIDES JAI SIKGIDIBIN Thssy 
equal average dips in opposite directions. The primary fold is 
composed of a set of secondary folds, which at the crest are 
upright, and in passing in either direction transverse to the 
Fic. 12.—Ideal section of an upright abnormal anticlinorium. 
primary axial plane the secondary folds are first inclined and 
then overturned. The two sets of secondary axial planes on 
opposite sides of the crest converge upward and diverge down- 
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Vian if \ we N Ne NG \ 
LE WISE ISSR RAS 
Lem bt CRG ' W “s AWS 
, WERARNSSS 
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SSNS LA BRERA 
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Fic. 13.—General section of roof structure in the central massif of the Alps. 
After Heim. 
ward. The secondary folds may be ordinary, isoclinal, or fan- 
shaped (Figs. 12 and 13). 
The inclined abnormal anticlinorium.—Vhe primary fold of the 
inclined abnormal anticlinorium has an inclined axial plane, and 
the limbs at corresponding points have unequal average dips in 
opposite directions. The primary fold is composed of a set of 
secondary folds, all of which are inclined or overturned. The 
two sets of secondary axial planes on opposite sides of the crest 
converge upward and diverge downward. The secondary folds 
may be ordinary, isoclinal, or fan-shaped. 
The overturned abnormal anticlinorium.—The primary fold of the 
overturned abnormal anticlinorium has an inclined axial plane, 
a i ACT 
