Faults

Question 1

any surface with measurable slip; discontinuity in a displacement field

Answer 1

faults

Question 2

slip occurs on several faults within a band of definable width

Answer 2

fault zone

Question 3

regions of localized but continuos ductile displacement

Answer 3

ductile faults

Question 4

fracturing, crushing, and frictional sliding of grains of rock

Answer 4

cataclasis

Question 5

Anderson’s Theory of Faulting

Answer 5

1 of the 3 principal stresses must be perpendiculat to the surface

Question 6

fault block beneath the fault surface

Answer 6

foot wall

Question 7

fault block above the fault surface

Answer 7

hanging wall

Question 8

relative offset of points once adjacent

Answer 8

displacement

Question 9

where a feature in the footwall is cut

Answer 9

footwall cut-off

Question 10

where a feature in the hanging wall is cut

Answer 10

hanging wall cut-off

Question 11

rocks that have been translated great distances

Answer 11

allochthonous

Question 12

rocks that have retained their location

Answer 12

autochthonous

Question 13

locally transported rocks

Answer 13

paraautochthonous

Question 14

geomorphic feature formed by the offset in a fault

Answer 14

fault scarp

Question 15

fault that intersected the surface

Answer 15

emergent fault

Question 16

fault that did not break the surface

Answer 16

blind faults

Question 17

largest fault in a zone

Answer 17

master fault

Question 18

dips toward the main fault

Answer 18

antithetic fault

Question 19

dips in the same direction as the fault

Answer 19

synthetic fault

Question 20

high angle, down-dip, extensional

Answer 20

normal

Question 21

low angle, up-dip, contractional

Answer 21

reverse

Question 22

where do normal faults form in

Answer 22

rifts, passive margins, mid-ocean ridges

Question 23

relay or parallel arrays

Answer 23

half-graben

Question 24

fault that decreases dip with depth, concave upward

Answer 24

listric fault

Question 25

normal faults dipping away from each other

Answer 25

horst

Question 26

normal faults dipping toward each other

Answer 26

graben

Question 27

bounded by a normal fault only on one side

Answer 27

half-graben

Question 28

low angle reverse fault placing allochthonous rocks over autochthonous or parautochthonous

Answer 28

thrust fault

Question 29

thrust fault run parallel then cup up through layers

Answer 29

flat-ramp structure

Question 30

thrust slices above a decollement along incompetent layers

Answer 30

duplex structure

Question 31

fan like splay of thrust panels

Answer 31

imbricate zone/ schuppen structure

Question 32

erosion created exposure of footwall rocks surrounded by hanging wall rocks

Answer 32

window/fenster

Question 33

an island of hanging wall rock

Answer 33

klippe

Question 34

right-lateral

Answer 34

dextral

Question 35

left-lateral

Answer 35

sinistral

Question 36

large strike-slip faults are also called

Answer 36

transcurrent faults/wrench faults

Question 37

strike slip between similarly oriented faults segments

Answer 37

transfer fault

Question 38

repeatedly offset the ocean ridges to accomodated differences in the spreading rates of either side of a ridge and or between neighboring segments

Answer 38

ridge-ridge

Question 39

links two destructive plate boundaries

Answer 39

trench-trench

Question 40

connects spreading to convergent plate boundaries

Answer 40

ridge-trench

Question 41

synchronously forms a subduction zone and a strike slip fault

Answer 41

shear partitioning

Question 42

both dip-slip and strike slip motion

Answer 42

oblique-slip faults

Question 43

the amount of slip changes along the strike

Answer 43

scissors fault

Question 44

displacement of one fault block relative to one another

Answer 44

net slip

Question 45

angle between the strike of the slip surface and slip vector

Answer 45

rake

Question 46

reltive displacement of one wall with respect to the other wall

Answer 46

sense of slip

Question 47

apparent displacement observed in a section

Answer 47

apparent separation

Question 48

separation of layers in a vertical section on a horizontal exposure or map

Answer 48

horizontal separation

Question 49

separation of layers in a vertical section

Answer 49

dip separation

Question 50

horizontal component of dip separation

Answer 50

heave

Question 51

vertical component of dip separation

Answer 51

throw

Question 52

missing straigraphic section in a wellbore indicates what fault

Answer 52

normal

Question 53

most intensely deformed part of a fault, crushed and shattered rock

Answer 53

fault core

Question 54

surrounding area of less deformation, fractures, subsidiary faults, and veins

Answer 54

damage zone

Question 55

non-foliated and incohesive rocks

Answer 55

fault gouge and fault breccia

Question 56

non-foliated and cohesive rocks

Answer 56

pseudotachylyte and cataclasite

Question 57

foliated and cohesive rocks

Answer 57

mylonite

Question 58

composed of angluar fragments > 1mm to several m in diameter

Answer 58

fault breccia

Question 59

composed of fine-grained rock flour

Answer 59

fault gouge

Question 60

fragments interlock and remain cohesive

Answer 60

cataclasite

Question 61

10% to 50% of the cataclasite is matrix

Answer 61

protocataclasite

Question 62

50% to 90% of the cataclasite is matrix

Answer 62

cataclasite

Question 63

90% to 100% of the cataclasite is matrix

Answer 63

ultracataclasite

Question 64

glass or microcrystalline that flowed in between rocks

Answer 64

pseudotachylyte

Question 65

well foliated and lineated and abundant evidence of plastic deformation

Answer 65

mylonites

Question 66

smoothly polished surface caused by movement along a fault

Answer 66

slickensides

Question 67

linear features in slickensides

Answer 67

slickenlines

Question 68

stylolitic surface facing the movement direction of the block

Answer 68

slickolite

Question 69

occurs when there is a rapid decrease in the fault tip

Answer 69

wing cracks

Question 70

develops where dip dies out gradually

Answer 70

horsetail splay

Question 71

finer and more closely spaces wing cracks

Answer 71

synthetic splay

Question 72

localized extension in shear zones

Answer 72

en echelon fractures

Question 73

sense of slip opposite to that of the main fault

Answer 73

antithetic splay

Question 74

subsidiary shear fractures that propagate out of the main fault

Answer 74

riedel shears

Question 75

first subsidiary fractures, 10 to 20 degrees to the main fault

Answer 75

R shear

Question 76

a second set of subsidiary faults; 75 degrees to the main fault

Answer 76

R' shears

Question 77

third set of subsidiary fractures

Answer 77

P shears