Map And Cross Section Interpretation

Question 1

Blind thrust

Answer 1

A thrust fault that does not reach the ground surface.

Question 2

Detachment fault

Answer 2

A low angle normal fault associated with refional movement.

Question 3

Dip-slip fault

Answer 3

A fault in whoch the movement isnparallel to the dip of the failt place. Known as a normal, reverse, or listric fault.

Question 4

Fenster

Answer 4

This is an erosional opening or a window where thr underlying rocks are exposed. This process is normally caused by erosion or normal faulting of a thrust system.

Question 5

Footwall block

Answer 5

The underlying block of a fault that has an inclined fault plane. This underlies a non-vertical fault.

Question 6

What does ‘Ga’ stand for?

Answer 6

This is an abbreviation for Giga-annum which is one billion years.

Question 7

What is GIS?

Answer 7

An abbreviation for geographic information system. This is a computer based tool that is used for mapping, analysing, and visualizing geographically refererenced data.

Question 8

What is GPS?

Answer 8

This is an abbreviation for global positioning system. This is a radio navigation system that determines the exact location, time, and velocity and determined by triangulation.

Question 9

What is a growth fault?

Answer 9

This is a fault that forms at the same time as deposition in sedimentary rock.

The throw [define] increases with depth and thr sedimentary units on the downthrown side are thicker than the corresponding units on the up thrown side.

Question 10

Define a hanging wall block.

Answer 10

This is the block that overlies a non-vertical fault.

Question 11

Define heave

Answer 11

This is the amount of horizontal displacement on a fault.

Question 12

What does ‘Ka’ represent?

Answer 12

This is the abreviation for Kilo-annum which means one thousand years.

Question 13

Define

klippe.

Answer 13

This is an outlier of a thrust sheet that is completely surrounded by the exposed foot wall.

Question 14

What are key beds?

Answer 14

These are well-defined, easily identified strata that is distinctive enough to be useful in correlation in mapping.

Question 15

What is a listric fault?

Answer 15

This is a fault woth a curved fault plane.

Near the surface the fault plane is steeply dipping, but becomes flatter with depth. These faults can be either normal or reverse.

Question 16

What does ‘Ma’ stand for?

Answer 16

This is an abbreviation for Mega-annum which means one millions years.

Question 17

What is magnetic declination?

Answer 17

This is the angle that is between true North and magnetic North.

Question 18

Define nappe.

Answer 18

This is a sheet-like rock unit that has moved over other rocks (allochthonous) on a predominately horizontal surface.

Question 19

Define net slip.

Answer 19

This is the distwnce between two formerly adjacent points on either side of the fault, measured on the fault surface.

Question 20

Define nonconformity.

Answer 20

This is an unconformity that is formed by older igneous rocks in contact with younger sediments, which indicates a missing time after the igneous intrusion.

Question 21

Define normal fault.

Answer 21

This is a dip-slip fault in which the hanging wall has moved down relative to the foot wall.

The dip of the fault is between 45 and 90 degrees.

Question 22

Define an oblique slip fault.

Answer 22

This is a fault in which movement is not parallel to the strike or dip of the fault plane.

Question 23

Define offset.

Answer 23

The horizontal component of displacement measured perpendicular to the strike of the disrupted unit.

Question 24

Define reverse fault.

Answer 24

A dip slip fault in which the hanging wall has moved up relative to the footwall. The dip of the fault is between 45 and 90 degrees.

Question 25

What is the rule of V’s?

Answer 25

This rule states that the outcrop pattern of a formation as it crosses a valley forms a V shape (map view). The V points in the direction that the formation underlies the valley.

Question 26

What is the state plane coordinate system?

Answer 26

This is a two dimensional coordinate system that was developed by the National Geodetic Survey for use in states and counties.

Question 27

Define strike separation.

Answer 27

The horizontal distance between a stratigraphic unit offset by a fault, measured along the strike of the fault. It is an apparent displacement.

Question 28

Define strike-slip fault.

Answer 28

A fault in which movement is parallel to the strike of the fault plane.

Question 29

Define throw.

Answer 29

This is the amount of vertical displacement on a fault, also, the vertical component of net slip.

Question 30

Define thrust fault.

Answer 30

This is a reverse fault in which the fault plane dips less than 45 degrees.

Question 31

Define unconformity.

Answer 31

This is a gap in the geologic record which signals an interruption in the depositional sequence that implies uplift and erosion have removed part of the geologic record or non- deposition has occurred.

Question 32

Name the four Eons. List youngest to oldest.

Answer 32

Phanerozoic Proterozoic Archaen Hadean

Question 33

What is the law of initial horizontality.

Answer 33

This law assumes that the sequence of layers were deposited horizontally or nearly so. The oldest layer is therefore on the bottom and the youngest layer is on top. In dissected topography, the youngest layers will form hill tops.

Question 34

What does the law of superposition state?

Answer 34

States that the oldest layer is on the bottom and the youngest layer is on the top and assumes that layers have not been overturned during formation. This law can be applied to any layered rock sequence such as sedimentary units or extrusive igneous rocks.

Question 35

Define cross cutting relationships.

Answer 35

These are useful in determining relative ages because cross cutting is so common. This implies that the feature that is cut is older than the feature that cuts across it and is cut by either intrusion, faulting, unconformities, or mineral replacement.

Question 36

Define the principal of lateral continuity.

Answer 36

This implies there are sedimentary layers that when deposited covered a large area extending laterally in all directions. Rocks are considered to be laterally continuous even though they may now be separated by uplift or erosion.

Question 37

How can faunal and floral succession be used to determine ages?

Answer 37

By looking at the evolutionary decelopment of fossils, a sequence of age can be deceloped. Older and more primitive fossils are usually found below younger fossils. Extinctons may break the pattern and new patterns emerge. Fossils may show distinct evolutionary trends which may be used to correlate with stratigraphic sequences in other areas.

Question 38

What is the law of inclusions?

Answer 38

This states that inclusions in a rock signify that the inclusions are older than the rocks in which they are included. Inclusioks may also provide clues of the provenance [define] at the time of formation.

Question 39

How can metamorphosed beds be used to determine age?

Answer 39

Imply that the metamorphosed beds are younger than the rock as it existed before metamorphism. Metamorphism occurs at the same time with igneous intrusion or tectonism that produced the metamorphism.

Question 40

Name the Periods from youngest to oldest.

Answer 40

``` Quarternary Tertiary Cretaceous Jurassic Triassic Permian Carboniferous Devonian Silurian Ordovician Cambrian ```

Question 41

Name the subperiods and the periods they are apart of.

Answer 41

Neogene and paleogene - tertiary Pennaylvanian and Mississippian - carboniferous

Question 42

Name the Epochs and the Periods theyre apart of.

Answer 42

Holocene, Pleistocene - quarternary Pliocene, Miocene - neogene Oligiocene, Eocene, Paleocene - paleogene

Question 43

Name the Eras

Answer 43

Cenozoic Mesozoic Paeozoic

Question 44

Name the feature.

Answer 44

Graded bedding

Question 45

Name the feature.

Answer 45

Truncated cross-bedding

Question 46

Namw the feature.

Answer 46

Ripple marks

Question 47

Name the feature.

Answer 47

Sole marks

Question 48

Name the feature.

Answer 48

Basal conglomerates

Question 49

Name the feature.

Answer 49

Rip-up clasts

Question 50

Name the feature.

Answer 50

Scouring or channeling

Question 51

Name the feature.

Answer 51

Mud cracks

Question 52

Name the feature.

Answer 52

Solution surfaces.

Question 53

Name the feature.

Answer 53

Pebble dents

Question 54

Name the feature.

Answer 54

Brqchiopod shells encrusted with barnacles.

Question 55

Name the feature.

Answer 55

Coral

Question 56

Name the feature.

Answer 56

Disjointed pelecypod shells

Question 57

Name the feature.

Answer 57

Worm tails

Question 58

Name the feature.

Answer 58

Burrows

Question 59

Name the feature.

Answer 59

Baked zone under lava flow

Question 60

Name the feature.

Answer 60

Vesicular lava flow

Question 61

Name the feature.

Answer 61

Pillow lavas