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Geology > Review for Exam > Flashcards

Review for Exam Flashcards

1
Q

What term describes the shape of a mineral in fine needle-like crystals?

A

Acicular.

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2
Q

What type of fracture does quartz exhibit?

A

Conchoidal

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3
Q

What term describes the tendency of certain minerals to split easily in certain regular directions?

A

Cleavage

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4
Q

Which scale is used to measure the hardness of minerals?

A

Mohs’ Scale of Hardness

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5
Q

What term describes minerals that can be beaten into new shapes?

A

Malleable

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6
Q

How is the age of rocks estimated based on the severity of radioactive decay experienced by radioactive material present in the rocks?

A

Radiometric dating

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7
Q

What property of minerals refers to their appearance in powdered form?

A

Streak

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8
Q

What term describes minerals found in detached masses of spherical, ellipsoidal, or irregular shape?

A

Concretionary or nodular

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9
Q

What is the term used to describe the property of minerals that allows them to return to their original shape after bending?

A

Elastic

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9
Q

Which mineral property is described as the nature of a broken surface?

A

Fracture

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10
Q

What apparatus can be used to measure the specific gravity of minerals or rocks that are not too small?

A

Walker Balance

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11
Q

What term describes minerals that exhibit a kidney-shaped form?

A

Reniform

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12
Q

Which mineral property is measured relative to a standard scale of ten minerals?

A

Hardness

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13
Q

What term describes minerals consisting of spheroidal aggregations resembling a bunch of grapes?

A

Botryoidal

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14
Q

What term describes minerals that exhibit a moss-like or tree-like form, generally produced by the deposition of a mineral in thin veneers on joint planes or in crevices?

A

Dendritic

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15
Q

What term describes minerals with no lustre?

A

Dull

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16
Q

What property of minerals refers to their weight relative to the weight of an equal volume of water?

A

Specific gravity

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17
Q

What term describes minerals consisting of closely packed small crystals growing into a cavity?

A

Drusy

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18
Q

What term describes minerals that show broad flat surfaces

A

Tabular

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19
Q

Which mineral property refers to the appearance of a mineral surface in reflected light?

A

Lustre

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20
Q

What term describes minerals that are capable of being cut with a knife?

A

Sectile

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21
Q

What property of minerals is useful in distinguishing various oxides of iron?

A

Streak

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22
Q

What term describes the response of a mineral to a hammer blow, cutting with a knife, and bending?

A

Tenacity

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23
Q

What defines the geometric shape of minerals, which are bounded by faces arranged in a regular manner?

A

Crystals

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24
Q

What are the angles between adjacent crystal faces for similar crystals of any particular mineral?

A

Constant

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25
Q

How many crystallographic axes intersect in a common origin within a crystal, defining the crystal faces?

A

Three or four

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26
Q

What divides a crystal into exactly similar halves, each being the mirror image of the other?

A

Plane of symmetry

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27
Q

How many classes of symmetry are defined by planes, axes, and centers of symmetry?

A

32

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28
Q

What is the smallest complete unit of pattern in the atomic structure of a crystal?

A

Unit cell

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29
Q

In which system are many crystals bounded by faces that are all similar?

A

Cubic System

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30
Q

What is a face in the Cubic System that cuts all three or more forms?

A

Pyramid

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31
Q

What are faces called in the Orthorhombic, Monoclinic, and Triclinic Systems that cut two lateral axes and are parallel to the vertical axis?

A

Prisms

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32
Q

What is a face that cuts any one axis and is parallel to the other two called?

A

Pinacoid

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33
Q

What term describes the phenomenon where two closely adjacent crystals have grown together with a crystallographic plane or direction common to both, but one reversed relative to the other?

A

Twin crystals

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34
Q

What is the ratio called when the angle of incidence is measured for air and is divided by the angle of refraction?

A

Refractive index (n)

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35
Q

What is the term for a mineral that divides a ray of light into two, resulting in two values of refractive index?

A

Doubly refractive or birefringent

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36
Q

What is the direction along which light entering a crystal is not split into two rays but passes through the crystal undivided called?

A

Optic axis

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37
Q

What is the property of minerals that have the same refractive index for light entering in any direction called?

A

Isotropic or singly refracting

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38
Q

What type of crystals have two optic axes and are therefore called biaxial?

A

Orthorhombic, Monoclinic, and Triclinic crystals

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39
Q

What are the two polaroids in a petrological microscope called?

A

Polarizer and analyser

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40
Q

What happens to the appearance of a slice of quartz cut perpendicular to the c-axis when viewed between crossed polars?

A

It appears completely black due to isotropy.

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41
Q

What is the difference in refractive index between the maximum and minimum values for a crystal called?

A

Birefringence

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42
Q

What phenomenon causes a slice of quartz cut obliquely to the c-axis to show a white or grey polarization color?

A

Birefringence

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43
Q

What is the term for a face in the orthorhombic crystal system that cuts all three or more forms?

A

Prism (pr)

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44
Q

What is the name for a face in the orthorhombic crystal system that cuts one lateral axis and is parallel to the other two?

A

Pinacoid (d)

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45
Q

What term describes a face in the orthorhombic crystal system that cuts one lateral and the vertical axis, and is parallel to the other lateral axis?

A

Dome

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46
Q

What phenomenon occurs when a ray of light traveling through one medium is bent or refracted upon entering another medium of different density?

A

Refraction

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47
Q

What is the constant ratio of sin i to sin r called when a ray of light passes from one medium to another?

A

Refractive index (n)

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48
Q

What is the refractive index for Canada balsam, and similar cements in which rock slices are mounted?

A

1.54

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49
Q

What term describes the property of a mineral that enables it to divide a ray of light into two?

A

Doubly refractive or birefringent

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50
Q

What is the direction in a calcite crystal along which light entering it is not split into two rays?

A

Optic axis

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51
Q

What type of minerals have only one value of refractive index for light vibrations traversing it?

A

Isotropic or singly refracting minerals

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52
Q

What are the two polaroids in a petrological microscope called, and how are they positioned?

A

Polarizer (below the stage) and analyser (above the stage), positioned at right angles to each other.

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53
Q

What is the term for the phenomenon where a birefringent mineral appears completely dark at intervals of 90° during rotation between crossed polars?

A

Extinction

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54
Q

How many times does extinction occur during each complete rotation of a birefringent mineral slice between crossed polars?

A

Four times

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55
Q

What is the term for the property of a mineral where extinction occurs when some crystallographic direction, such as its length or prominent cleavage, is brought parallel to a cross-wire?

A

Straight extinction

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56
Q

What is the term for the property of a mineral where extinction occurs when its length makes an angle with the cross-wire?

A

Oblique extinction

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57
Q

What term describes the phenomenon where some minerals exhibit a change of color when rotated above the lower polarizer on the stage of a microscope?

A

Pleochroism

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58
Q

What are minerals called that appear dark brown or black when viewed through a microscope due to their inability to transmit light?

A

Opaque minerals

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59
Q

How are opaque minerals illuminated when studied with a microscope?

A

They must be illuminated from above.

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60
Q

In which mineral group are the SiO4 tetrahedra arranged in pairs with aluminum atoms between them, separated by layers of potassium atoms?

A

Micas and other flaky minerals

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61
Q

What type of atomic structure is formed when each SiO4 tetrahedron is linked by all four oxygens, sharing them with adjacent groups?

A

Three-dimensional Frameworks

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62
Q

What method can be used to investigate the atomic structure of crystals?

A

X-ray analysis

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63
Q

Composition: (MgFe)2SiO4
Crystal System: Orthorhombic
Color: Pale olive-green or yellow
Lustre: Vitreous
Fracture: Conchoidal
Hardness (H): 6
Specific Gravity (G): 3.2 to 3.6
Pleochroism: Strong
Extinction: Straight

A

Olivine

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64
Q

Composition: Enstatite - MgSiO3; Hypersthene - (MgFe)SiO3
Color: Dark brown or green (Hypersthene nearly black)
Lustre: Vitreous to metallic
Cleavage: Two good directions parallel to prism faces
Hardness (H): 5 to 6
Specific Gravity (G): 3.2 to 3.5
Pleochroism: Enstatite weak, Hypersthene strong
Extinction: Straight

A

Enstatite and Hypersthene (Orthorhombic Pyroxenes)

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65
Q

Composition: (CaMgFeAl)(SiAl)2O6
Color: Brown to black
Lustre: Vitreous to resinous
Twinning: Shows a re-entrant angle
Hardness (H): 5 to 6
Specific Gravity (G): 3.3 to 3.5
Pleochroism: Generally absent or weak
Extinction: Oblique

A

Augite (Monoclinic Pyroxene)

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66
Q

Composition: KAl2(Si3Al)O10(OH)2
Color: White (unless impurities present)
Lustre: Pearly
Cleavage: Perfect parallel to the basal plane
Hardness (H): 2 to 2.3
Specific Gravity (G): About 2.9
Pleochroism: Strong
Extinction: Straight

A

Muscovite (Mica)

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66
Q

Composition: (CaMgFeNaAl)2-3(AlSi)5-6O22(OH)2
Color: Dark brown or greenish black
Lustre: Vitreous
Cleavage: Two directions intersecting at 124°
Hardness (H): 5 to 6
Specific Gravity (G): 3 to 3.4
Pleochroism: Strong in shades of green, yellow, and brown
Extinction: Oblique

A

Hornblende (Amphibole)

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67
Q

Composition: K(MgFe)3AlSi3O10(OH)2
Color: Brown to nearly black
Lustre: Sub-metallic or pearly
Cleavage: Perfect parallel to the basal plane
Hardness (H): 2.5 to 3
Specific Gravity (G): 2.8 to 3.1
Pleochroism: Strong, shades of brown and yellow
Extinction: Parallel to the cleavage

A

Biotite (Mica)

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68
Q

Composition: KAlSi3O8
Crystal System: Monoclinic
Color: White or pink
Lustre: Vitreous
Cleavage: Two good cleavages intersecting at 90°
Special Features: Frequently twinned (Carlsbad, Manebach, Baveno)
Hardness (H): 6
Specific Gravity (G): 2.56
Mean Refractive Index (R.I.): 1.52
Birefringence (Biref): Weak
Extinction: Oblique

A

Orthoclase (Potassium Feldspar)

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69
Q

Composition: KAlSi3O8
Crystal System: Triclinic
Color: White, pink, or green
Lustre: Vitreous
Special Features: Similar to orthoclase
Hardness (H): Not specified
Specific Gravity (G): Not specified

A

Microcline (Potassium Feldspar)

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70
Q

Composition: KAlSi3O8
Crystal System: Triclinic
Color: Not specified
Lustre: Not specified
Cleavage: Not specified
Hardness (H): Not specified
Specific Gravity (G): Not specified

A

Anorthoclase (Potassium Feldspar)

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71
Q

Composition: Albite (NaAlSi3O8); Anorthite (CaAl2Si2O8)
Crystal System: Triclinic
Color: White or colorless (albite) to grey (anorthite)
Lustre: Vitreous
Cleavage: Not specified
Hardness (H): 6 to 6+
Specific Gravity (G): 2.60
Mean Refractive Index (R.I.): 1.55
Birefringence (Biref): Weak
Extinction: Oblique

A

Plagioclases

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72
Q

Composition: KAlSi2O6
Color: Not specified
Lustre: Not specified
Cleavage: Not specified
Hardness (H): Not specified
Specific Gravity (G): Not specified

A

Leucite (Feldspathoid)

73
Q

Composition: NaAlSiO4
Color: Not specified
Lustre: Not specified
Cleavage: Not specified
Hardness (H): Not specified
Specific Gravity (G): Not specified

A

Nepheline (Feldspathoid)

74
Q

Composition: SiO2
Crystal System: Trigonal
Color: Colorless when pure
Lustre: Vitreous
Fracture: Conchoidal
Special Features: No twinning, lack of alteration
Hardness (H): 7
Specific Gravity (G): 2.66
Mean Refractive Index (R.I.): 1.553 (max), 1.544 (min)
Birefringence (Biref): Weak
Extinction: Straight

A

Quartz

75
Q

Composition: SiO2
Color: White or brownish
Lustre: Waxy
Fracture: Conchoidal
Special Features: Straight extinction
Mean Refractive Index (R.I.): 1.54

A

Chalcedony

76
Q

Composition: SiO2
Color: Black
Fracture: Conchoidal

A

Flint

77
Q

Composition: Hydrated silica (SiO2 · nH2O)
Color: White, grey, or yellow
Lustre: Pearly
Fracture: Conchoidal
Hardness (H): About 6
Specific Gravity (G): 2.2

A

Opal

78
Q

Composition: ZrSiO4
Crystal System: Tetragonal
Hardness (H): 7.5
Specific Gravity (G): 4.7

A

Zircon

79
Q

Composition: Al2SiO5
Crystal System: Orthorhombic
Color: Pink or grey
Hardness (H): 7.5

A

Andalusite

80
Q

Composition: CaTiSiO5 (with variations in composition)
Crystal System: Monoclinic
Hardness (H): 5
Specific Gravity (G): 3.5

A

Sphene (Titanite)

81
Q

Composition: (Ca, Mg, Fe2+, Mn)3(Al, Fe3+, Cr)2(SiO4)3
Crystal System: Cubic
Color: Pale pink
Hardness (H): 6.5 to 7.5
Specific Gravity (G): 3.5 to 4.0
Special Features: Isotropic in thin section

A

Garnet

82
Q

Composition: Complex, typically a boron silicate mineral
Crystal System: Trigonal
Color: Black, red, green, blue
Hardness (H): 7
Specific Gravity (G): 3.0
Extinction: Parallel

A

Tourmaline

83
Q

Composition: Mg2Al4Si5O18
Crystal System: Orthorhombic

A

Cordierite (Iolite)

84
Q

Color: Shades of bluish-green and yellowish-green
Lustre: Vitreous
Hardness (H): 2 to 2.5
Specific Gravity (G): 2.65 to 3.0
Cleavage: Often observed
Mean Refractive Index (R.I.): About 1.58
Birefringence (Biref): Weak grey

A

Chlorite

85
Q

Color: Green, may be red if iron oxide is present
Hardness (H): 3 to 4
Specific Gravity (G): 2.6

A

Serpentine

86
Q

Color: White or greenish
Hardness (H): 1

A

Talc

87
Q

Composition: Kaolinite
Color: White or grey
Specific Gravity (G): 2.6

A

Kaolin (China Clay)

88
Q

Composition: Ca2(Al, Fe)3(SiO4)3(OH)
Color: Typically yellowish-green
Hardness (H): 6 to 7
Specific Gravity (G): 3.4

A

Epidote

89
Q

Colors: White or glassy
G: Varies (Analcite: 2.25, Natrolite: 2.2)
Crystal Systems: Cubic (Analcite); Orthorhombic (Natrolite)

A

Zeolites (Analcite, Natrolite)

90
Q

These layers are formed by the linking together of tetrahedral SiO4 groups. The composition of this layer is typically Si2O5 or Si2O5(OH)4.

A

Tetrahedral Layers

91
Q

These layers contain a metal ion (such as Al or Mg) surrounded by six hydroxyls arranged at the corners of an octahedron.

A

Octahedral Layers

92
Q

Composition: Al2Si2O5(OH)4
Structure: Consists of stacked layers of silicon-oxygen sheets and aluminum hydroxyl layers.

A

Kaolinite

93
Q

Structure: Built up of 3-layer units with variable water content. Absorption of water between the layers leads to significant swelling properties.

A

Montmorillonite

94
Q

Composition: Variable, typically a mixture of potassium, aluminum, and silicon.
Occurrence: Widely distributed in marine sediments, often found in shales.

A

Illite

95
Q

Clay material Similar composition to kaolinite but with a different layer arrangement

A

Dickite

96
Q

Often included with dickite and kaolinite, occurring as minute tubes.

A

Halloysite

97
Q

A less common clay mineral.

A

Ilfite

98
Q

typically mixtures of illite, kaolinite, and montmorillonite.

A

Sedimentary clays

99
Q

often contain illite as the dominant clay mineral.

A

Shales

100
Q

Structure: Cubic
Properties: Colorless or nearly colorless varieties are valued as gemstones. Used as abrasives in granular aggregates (bort).

A

Diamond

101
Q

Structure: Hexagonal
Properties: Very soft mineral, used as a lubricant. Occurs in veins or lenticular patches.

A

Graphite

102
Q

(Lead Sulphide):
Crystals: Cubic

A

Galena

103
Q

(Zinc Sulphide):
Crystals: Cubic, often as tetrahedra

A

Sphalerite

104
Q

(Copper Iron Sulphide):
Crystals: Tetragonal

A

Chalcopyrite

105
Q

(Iron Sulphide, “Fool’s Gold”):
Crystals: Cubic

A

Pyrite

106
Q

Properties: Magnetic, soluble in HCl

A

Pyrrhotite

107
Q

(Mercury Sulphide):
Chief ore of mercury

A

Cinnabar

108
Q

Occurs in deposits from the evaporation of saltwater bodies

A

Halite (Rock Salt, Sodium Chloride)

109
Q

Oxides and Hydroxides

A

Haematite (Iron Oxide, Hematite):
Crystals: Trigonal rhombohedral
Ilmenite (Titanium Iron Oxide):
Chief ore of titanium
Magnetite (Iron Oxide):
Crystals: Cubic
Chromite (Iron Chromium Oxide):
Crystals: Cubic
Cassiterite (Tin Oxide):
Chief source of tin
Bauxite (Aluminium Ore):
Source of aluminium

110
Q

Carbonates

A

Calcite (Calcium Carbonate):
Crystals: Trigonal
Properties: Principal source of carbonate of lime. Recognized by perfect cleavage and its reaction with dilute acids.
Aragonite: Orthorhombic
Siderite (Iron Carbonate):
Crystals: Rhombhedral
Malachite (Copper Carbonate):
Valuable ore of copper and ornamental stone.

111
Q

What is the term used to describe weathering effects attributed to plants and animals?

A

Biological weathering

112
Q

What term refers to the weathering effects caused by plants and animals, promoting the solvent action of water and the formation of organic acids?

A

Biological weathering

113
Q

In which regions, characterized by rapid evaporation nearly equal to rainfall, can mineral deposits build up due to the retention of dissolved salts by capillarity?

A

Previously hot, semi-arid regions

114
Q

Which classification system reflects the relationship between soil type and weathering type, based on climate?

A

Soil classification according to climatic zones

115
Q

What are the agents capable of loosening, dislodging, and carrying particles of soil, sediment, and rock?

A

Agents of erosion (such as rivers, wind, moving ice, and water waves)

116
Q

What term refers to the area drained by a river and its tributaries?

A

atchment or river basin

117
Q

What topographical form is used to describe flat-topped hills resulting from partly denuded horizontal strata capped with hard rock?

A

Mesa

118
Q

In erosion, what type of slope results when the rate of removal exceeds the rate of supply?

A

Convexo-concave slopes

119
Q

If rock layers are inclined in one direction and the river flows parallel to the hard layers, what landforms are carved in the softer beds?

A

Long hollows or vales separated by ridges of harder rock, forming escarpments

120
Q

What method estimates the age of rocks based on the severity of radioactive decay experienced by radioactive material present in the rocks?

A

Radiometric dating

121
Q

How much does the ground’s temperature increase with depth assuming no nearby sources of heat?

A

0.03 Celsius per meter or 30 Celsius per kilometer

122
Q

What term describes the level of the sea or lake into which a river discharges?

A

Base-level

123
Q

What is the term for the break in slope at the junction of the old river course with the new, deeper cut?

A

Nick-point

124
Q

What are formed where a river flows over rocks of differing hardness, resulting in undercutting and the formation of overhanging ledges?

A

Rapids and waterfalls

125
Q

What term describes the deposits laid down by rivers and may include fine material such as silt and mud as well as coarse sand and gravel?

A

Alluvium

126
Q

What term refers to the deposits left on the old valley floor by a river after it cuts down its channel to lower levels?

A

Terraces

127
Q

What structures, found in river-deposited and other shallow-water sediments, are known as current-bedding or cross-bedding?

A

Current-bedding or cross-bedding

128
Q

What term describes the process where a river, after having deposited alluvium on a flood plain, cuts down its channel to lower levels, leaving remnants of earlier deposits on the old valley?

A

Rejuvenation

129
Q

What term refers to the deepening of valleys during glaciations when sea levels were lower and rivers cut down into their valley floor to re-establish their grade?

A

Valley deepening

130
Q

What type of deposits are usually very porous and compressible if rich in clay, and permeable if composed mainly of silt, sand, or gravel?

A

Alluvium

131
Q

What term describes the term given to the situation where a river swings from side to side of its valley and eventually flows in big loops?

A

Meandering

132
Q

What term describes the deposits laid down by rivers when they enter a body of water, such as a lake or the sea?

A

Deltas

133
Q

What is the process called where each flood brings down sediment, and coarser material is dropped in front of the growing pile, building up foreset beds?

A

Sediment deposition

134
Q

What term describes the deposits left on the old valley floor by a river after it cuts down its channel to lower levels?

A

Terraces

135
Q

What is the term for the periodic rise and fall of the sea due to the pull exerted by the sun and moon on the globe?

A

Tides

136
Q

What term describes a water movement that is quickly generated and soon over?

A

Tidal surges

137
Q

What term describes wave motion produced when a water surface is swept by wind?

A

Wave motion

138
Q

What type of waves are characterized by an up-and-down movement imparted to the water at the cliff face?

A

Reflected waves

139
Q

What term describes waves that run in over a long distance in gradually shallowing water?

A

Storm waves

140
Q

What coastal feature is formed at the base of many coastal cliffs, sloping gently seawards, and beveling off rocks of the foreshore?

A

Wave-cut platform

141
Q

What types of coasts are the result of submergence, where there is a rise of sea-level relative to the land?

A

Submergent coasts

142
Q

What term describes the process of the sea exerting a ‘sawing’ action at the base of cliffs, cutting a horizontal notch which weakens the cliff base?

A

Cliff erosion

143
Q

What is the name for the isolated pillars of rock or sea-stacks formed when erosion in jointed rocks leaves behind resistant rock structures?

A

Sea-stacks

144
Q

What type of coastline results from a rise of the land relative to the sea, eventually giving a nearly smooth coastline bordering an area of newly exposed sea-floor?

A

Coast of emergence

145
Q

What term describes the deposits of very fine particles of mud that settle due to flocculation?

A

Settlement

146
Q

What are the deposits of coarser particles built up at the angle of repose in water ahead of the growing pile of sediment called?

A

Foreset beds

147
Q

What term describes the wave motion that diminishes with depth from the surface, ceasing almost entirely at a depth equal to the wavelength?

A

Wave interference

148
Q

What is the name for the zone extending from the base of the cliffs down to low-water mark along the coast?

A

Shore

149
Q

What are the waves characterized by interference with the sea floor and friction, resulting in a reduction in size before breaking?

A

Swell waves

150
Q

What is the name for the zones in front of growing deltas where the finer material is deposited in the deeper water?

A

Bottomset beds

151
Q

What term describes the rocks of the foreshore being exposed on a gently sloping platform formed at the base of coastal cliffs?

A

Wave-cut platform

152
Q

What term describes the sandy ridge formed by longshore drift, extending out into open water from a bend in the coast?

A

Spit

153
Q

What type of barrier forms when a spit extends across a bay, lying across the mouth of a small estuary, with a lagoon behind it?

A

Bay-bar or barrier

154
Q

What are the elongated parallel islands composed essentially of sand, separated by inlets, called?

A

Barrier islands

155
Q

What is the depth at which a balance exists between supply and dissolution rates, known as?

A

Calcite compensation depth

156
Q

What type of sediment slowly accumulates on the ocean floor at rates of between 1 and 50 mm per 1000 years in the open sea?

A

Pelagic sediments

157
Q

What term describes the nearly spherical forms with frosted surfaces that wind-blown sand grains become worn down to?

A

Eolian sand

158
Q

What are the deposits of wind-blown fine particles separated from sand and carried over large distances called?

A

Loess

159
Q

What notable feature associated with arid and wind-swept landscapes are residual peaks of hard rock left upstanding and wind polished above the general level?

A

Inselbergs (or ‘island mounts’)

160
Q

What is the term for the work of denudation by wind, most prominently seen in regions with a hot, dry climate?

A

Wind erosion

161
Q

What term describes the deposits of sediment laid down on the continental shelf by feeble currents out to sea?

A

Coastal marine deposits

162
Q

What are the largest forms of desert dunes generally composed of?

A

Coarsest sand

163
Q

What type of dunes have a crescent shape and are found in areas with a nearly constant wind direction and limited sand supply?

A

Barchan dunes

164
Q

What is the wind-blown deposit known as loess primarily composed of?

A

Fine-grained calcareous clay or loam

165
Q

What is the intermediate stage between snow and ice called?

A

Neve

166
Q

What term describes the deposits left behind by a glacier or ice-sheet?

A

Glacial drift

167
Q

What term refers to the debris dropped at the front of a glacier as the ice melts, forming a hummocky ridge?

A

Terminal moraine

168
Q

What are the smooth oval-shaped mounds composed of boulder clay or englacial debris, sometimes molded over a roche moutonnee, called?

A

Drumlins

169
Q

What term describes the tapered columns of soil each capped by a large stone or boulder formed by rain denudation in areas of thick soil containing embedded boulders?

A

Earth pillars

169
Q

What is the general term used to describe the transport of material down a slope, including mechanisms like landslides?

A

Mass-movement

170
Q

What term refers to the repeated, small-scale mass-movement on hills of hard rock that creates escarpments?

A

Colluvium

170
Q

What percentage of the Earth was glaciated during the Pleistocene?

A

ore than one-third

171
Q

What is the upward growth of a salt-marsh that accumulates further sediment called?

A

Salt-marsh accretion

171
Q

What feature is formed when land ice meets the sea and begins to float and break up into icebergs?

A

Calving

171
Q

What term describes the deposits of subglacial debris produced by melt water from the glacier?

A

Lodgement till

172
Q

What term describes the wind-blown deposit composed of fine grained deposits of oceanic clay, wind-blown sand, and volcanic dust accumulating on the ocean floor?

A

Pelagic sediments

172
Q

What term refers to the material held in the lower part of moving ice that acts as an abrasive, smoothing and polishing the underlying rock surface?

A

Englacial material

172
Q

In what type of lakes did upland lakes often develop, dammed by the glacier of the main valley?

A

Hanging valleys

172
Q

What type of dunes develop from small heaps of sand not less than 30cm in height and are found in areas where the wind blows from a nearly constant direction?

A

Barchan dunes

173
Q

What are the deposits left behind by a glacier or ice-sheet called, which is generally thickest in valleys and lacks sorting and arrangement?

A

Glacial drift

174
Q

What term describes the fine-grained laminated clays deposited in still water impounded in front of a retreating glacier or in glacial lakes?

A

Varves

Geology (6 decks)

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