Term
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Definition
-local steepening
-uniformly dipping strata |
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Term
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Definition
| -upfold in a form of arch in layered rocks |
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Term
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Definition
| -downfold with a trough-like form in layered rock |
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Term
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Definition
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Term
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Definition
-imaginary plane dividing fold symmetrically
-passes through axis
-bisect
(reflects stress direction) |
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Term
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Definition
-imaginary line drawn on fold surfaces which intersecting with axial plane
-median line b/w limbs
-along crest of ancline or trough of syncline
-flat or plunge into ground
(reflects stress directions) |
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Term
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Definition
-two limbs dip gently & equally away from axis
-the more compressional stress, less open the fold
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Term
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Definition
| -intense stress= fold closes up, limbs become parallel |
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Term
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Definition
intense stress causing
-limbs have unequal dips |
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Term
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Definition
intense stress causing
-limbs dip same direction
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Term
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Definition
-recumbent=two limbs are horizontal or nearly so
-mountain regions
(continental collision)
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Term
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Definition
-fold with incline axis
(plunge=angle b.w fold axis and horizontal) |
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Term
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Definition
-anticlinal structure
-oldest rocks at center,younger rocks at edges |
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Term
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Definition
-synclinal structure
-youngest rocks in center, older at edges |
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Term
| Folds and Plate Tectonics |
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Definition
-mountains
(compressional stress & magmatic activity)
-by plate motion |
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Term
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Definition
| -compass orientation of line described by intersection of (tilted and horizontal surface) |
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Term
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Definition
| -gives the idea of stress direction |
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Term
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Definition
-down surface compass direction at right angle to strike
-angle measured b/w dipline and horizontal
-the intensity of movement |
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Term
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Definition
-bend or warp in layered rocks
-formed by ductile deformation
(compressional and and shear stress) |
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