Exam

Question 1

Folds are classified based on their orientations. Which of these below shows shallow plunge of hinge line?

A. 60-80°
B. 30-60°
C. 10-30°
D. 0-10°

Answer 1

C. 10-30°

Question 2

Which of these shows gentle interlimb angle?

A. 180-170°
B. 170-90°
C. 90-10°
D. 10-0°

Answer 2

A. 180-170°

Question 3

Isoclinal is a fold arrangement conferring to?

A. Age of Strata
B. axial plane orientation
C. Interlimb angle
D. layer thickness

Answer 3

C. Interlimb angle

Question 4

Is this true? Rectangular boudins imply higher competence contrast and more brittle deformation than barrel-shaped boudins.

A. Uhm, yes
B. Uhm, no
C. No, because the latter indicates higher competency contrast but with more ductile deformation
D. Yes, but the latter also implies a higher competency contrast

Answer 4

A. Uhm, yes

Question 5

It is a series of similarly oriented reverse faults that are connected through a low-angle floor

A. Duplex Structure
B. Horses
C. Imbrication Zone
D. Extensional Duplex
E. Accommodation zone
F.Horst

Answer 5

C. Imbrication Zone

Question 6

What are disharmonic folds?

A. folds that are not balanced in a structure
B. folds that die out in a short distance
C. folds that lean or have a short limb
D. folds that are irregular and not harmonic

Answer 6

B. folds that die out in a short distance

Question 7

These are linear structures that formed at the initial stage of fracture growth and may be polished and striated as slip accumulates

A. Striations
B. Chatter Marks
C. Currogations
D. Slickenlines
E. Strations
F. Corrugations
G. Ridge-in-groove lineations

Answer 7

F. Corrugations

Question 8

It is boudinage in two directions, indicating two directions of finite extension within the layer implying flattening strain forming more or less square or rectangular boudins in three dimensions. What do you call it?

A. Asymmetric foliation boudinage
B. rectangular boudinage
C. Symmetric foliation boudinage
D. chocolate tablet boudinage

Answer 8

D. chocolate tablet boudinage

Question 9

Foliation in coarse-grained metamorphic rocks, that appears as a parallel, planar arrangement of elongated or platy mineral grains is called?

A. quartzitic banding
B. schistocity
C. gneissic banding
D. schistosity
E. phyllitic cleavage
F. gniessic banding

Answer 9

D. schistosity

Question 10

What type of fault displaces the hanging wall toward the hinterland, i.e. opposite to the general thrusting direction?

A. roof thrust
B. back-thrust
C. sole thrust
D. horst
E. horse

Answer 10

B. back-thrust

Question 11

These are small folds geometrically related to large-scale fold. Classified as M, S, and Z shaped.

A. Ptygmatic folds
B. Disharmonic folds
C. Kink folds
D. Chevron folds
E. Parasitic folds

Answer 11

E. Parasitic folds

Question 12

Shortening of crustal layers can result in a wide range of strain regimes and structures below, except:

A. dilation and cleavage formation
B. imbrication
C. slumping
D. none of the above
E. pure shear without folding

Answer 12

C. slumping

Question 13

An erosional remnant of a nappe is called what?

A. Window
B. Fault Outlier
C. Outlier
D. None of the Above

Answer 13

C. Outlier

Question 14

A nappe is allochthonous, leaving a fault inlier called?

A. Klippe
B. Fester
C. Autochthonous Material
D. Outlier
E. Window

Answer 14

E. Window

Question 15

Which of the ff. is not an example of fold classification according to interlimb angle?

A. asymmetrical
B. overturned
C. plunging
D. gentle
E. None of the above

Answer 15

C. plunging

Question 16

Presence of sulfur in salt domes are typical

A. True
B. False
C. Neither True or False
D. partly False

Answer 16

A. True

Question 17

What type of structure is this→MMM

A. concentric folds
B. conjugate folds
C. chevron folds
D. kink bands

Answer 17

C. chevron folds

Question 18

Which of the ff. rocks will show pencil cleavage?

A. claystone
B. sandstone
C. shale
D. limestone

Answer 18

C. shale

Question 19

Alternating or segregated felsic and mafic layers (lepidoblastic biotites amphiboles) due to metamorphic differentiation or to local partial melting.

A. transposition
B. crenulation cleavage
C. slaty cleavage
D. schistosity
E. gneissic layering

Answer 19

E. gneissic layering

Question 20

A texture is built of minerals and mineral aggregates with a preferred orientation that penetrate the rock at the microscopic to centimeter spacing scale.

Answer 20

False

Question 21

Cleavage is the low-temperature version of foliation and is best developed in rocks with abundant elongated minerals.

Answer 21

False

Question 22

Stylolitic cleavage is a type of compaction cleavage.

Answer 22

False

Question 23

Bending occurs when a competent layer in a less competent matrix is shortened parallel to the length of the layer.

Answer 23

False

Question 24

The minimum principal stress axis bisects the acute angle of conjugate faults.

Answer 24

False

Question 25

In-sequence thrusting enables the zone of contractional deformation to expand in the hinterland direction consistent with progressive broadening of active collision zones.

Answer 25

False

Question 26

A classic fault-bend-fold forms where a tectonic unit is passively transported over a ramp (bend) in its sole thrust.

Answer 26

True

Question 27

These are structures in which the beds dip away from a central point sometimes called doubly plunging anticlines_____________

Answer 27

DOMES

Question 28

A preferred orientation of clasts and phenocrysts obtained during sedimentation or crystallization is called_________________

Answer 28

PRIMARY FABRICS

Question 29

____________is generally used for any fabric-forming planar or curviplanar structure in a metamorphic rock, but may also include primary sedimentary bedding or magmatic layering

Answer 29

FOLIATION

Question 30

Classification of folds relative to hinge curvature is referred to as______________

Answer 30

BLUNTNESS

Question 31

_______________are two intersecting faults that formed under the same stress field. Such faults show opposite sense of shear and make 30° or an acute angle to sigma 1

Answer 31

CONJUGATE FAULTS

Question 32

6-7. The ____________ is the area in the central portion of the collision zone, and the ______________is the marginal part and thus farthest into the continent.

Answer 32

HINTERLAND, FORELAND

Question 33

________________are exposed portion (window) of the metamorphic rocks of the lower plate (footwall) of a low-angle normal fault (detachment). According to the original use of this term, the upper plate should be exposed to brittle deformation while the lower one contains mylonitic rocks formed in the plastic regime.

Answer 33

METAMORPHIC CORE COMPLEX

Question 34

________________is a large sheetlike body of rock that has been displaced by thrust faulting more than 2 to 5 km from its original position, formed during collisional tectonics.

Answer 34

NAPPE

Question 35

________________is the term which describes a tectonic unit that has been transported too far for direct correlation with the substrate.

Answer 35

ALLOCHTHONUS

Question 36

Slices of basement and perhaps its sedimentary cover thrust only a few kilometers or so are called_________________________

Answer 36

PARAUTOCHTHONOUS

Question 37

12-13. Contractional regimes create different foreland and hinterland deformation styles. ________________involves the shortening of Hinterland basement and consists of mostly metamorphic and magmatic rocks. While ________________ is characterized by deformed foreland areas where clastic thrust structures with duplexes and related folds appear.

Answer 37

THICK-SKINNED TECTONICS THIN SKINNED TECTONICS

Question 38

The term _______________ refers to the ability of a rock to split into more or less parallel surfaces.

Answer 38

CLEAVAGE

Question 39

A spaced, usually disjunctive cleavage_______________

Answer 39

SOLUTION CLEAVAGE

Question 40

__________________is commonly used about early tectonic domainal cleavage in previously unfoliated rocks such as mudstones, sandstones and limestones. This term implies that the cleavage cuts across, rather than crenulating (folding), preexisting foliations.

Answer 40

DISJUNCTIVE CLEAVAGE

Question 41

The attitude of a linear structure________________

Answer 41

TREND

Question 42

_____________________is a tectonic unit or structure consisting of a series of typically S-shaped structures dipping toward the hinterland that are between a sole and a roof thrust.

Answer 42

DUPLEX

Question 43

_______________is a type of point defect wherein gaps in between atoms are occupied by another atom.

Answer 43

INTERSTITIAL

Question 44

_________________is the angle made by the linear structure with the horizontal, in the vertical plane parallel to its trend.

Answer 44

PLUNGE

Question 45

The smooth, grooved slip surface itself is called a ____________

Answer 45

SLICKENSIDES

Question 46

____________________typically has an S-shaped geometry in the vertical profile and they tend to dip toward the hinterland

Answer 46

HORSE

Question 47

_______________generated by simple shearing are perfectly similar folds.

Answer 47

PASSIVE FOLDS

Question 48

What fold is produced during a progressive development (shown below) from a contractional deformation __________________

Answer 48

FAULT- PROPAGATION FOLD