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Correlation 1 > Igneous Petrology > Flashcards

Igneous Petrology Flashcards

1
Q

is molten rock material generated by partial melting of Earth’s mantle and crust

A

Magma

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2
Q

magma that rises and erupts onto the surface of Earth

A

Lava

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3
Q

is the liquid portion, is composed mainly of mobile ions of the eight most common elements in the crust.

A

Melt

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4
Q

the gaseous components of magma, are materials that will vaporize (form a gas) at surface pressures

A

Volatiles

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5
Q

called when magma loses its mobility before reaching the surface it eventually crystallizes

A

Intrusive

Plutonic

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6
Q

called when igneous rocks form by solidification of lava and volcanic debris on Earth’s surface, producing rocks with small crystals and/or non-crystalline particles of various sizes.

A

Extrusive

Volcanic

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7
Q

refers to the partial melting of a source rock

A

Anatexis

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8
Q

The type of magma produced by partial melting and subsequent processes depends upon factors such as:

A

The composition, temperature and depth of the source rock.

The percent partial melting of the source rock.

The source rock’s previous melting history. - Diversification processes that change the composition of the magma after it leaves the source region.

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9
Q

Ways of Generating Magma from solid rock

A

Increase in Temperature
Heat Transfer
Decrease in Pressure
Flux Melting

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10
Q

also known as adiabatic melting , results from a decrease in pressure.

occurs where hot, solid mantle rock ascends in zones of convective upwelling, thereby moving into regions of lower pressure

A

Decompression Melting

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11
Q

Crystallization along the walls of the magma chamber in which crystals preferentially form and adhere to the edges results in marginal accretion.

A

Marginal Accretion

Inward Crystallization

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12
Q

includes fractionation processes that occur when crystals develop with significantly different densities than the surrounding magma.

A

Gravitational Separation

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13
Q

occurs when higher density, ferromagnesian crystals settle to the base of a magma chamber relative to the lower density liquid magma

A

Crystal Settling

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14
Q

can occur if early formed crystals, such as plagioclase, are less dense than the magma

A

Crystal Flotation

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15
Q

occurs whereby liquids and crystals are segregated due to factors such as velocity, density or temperature.

A

Convective Flow Segregation

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16
Q

process whereby a magma chamber containing a mix of crystals and liquids is compressed, squeezing out the more mobile liquid into a new chamber and leaving behind a crystal residue in the original chamber.

A

Filter Pressing

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17
Q

involves the preferential diffusion of select ions within the magma in response to compositional, thermal or density gradients as well as water content.

A

Differential Diffusion

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18
Q

also called liquid – liquid fractionation , occurs when magma separates into two or more distinct immiscible liquid phases

A

Liquid Immiscibility

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19
Q

occurs when two or more dissimilar magmas coexist, displaying contact relations but retaining their distinctive individual magma characteristics.

A

Magma Mingling

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20
Q

implies thorough mixing so that the individual magma components are no longer recognizable.

A

Magma Mixing

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21
Q

record a progressive decrease in iron and magnesium with increasing SiO2 and alkali concentrations

A

Calc-alkaline Magma

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22
Q

with increasing fractionation, experience iron enrichment at low to moderate SiO2 concentrations

A

Tholeiitic Magma

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23
Q

are highly enriched in Na2O and/or K2O and are less common than either calc-alkaline or tholeiitic magmas or rocks

A

Alkaline Magma

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24
Q

are characterized by the voluminous occurrence of silicic and basic rocks with few intermediate rocks

A

Bimodal Magma Suites

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25
Q

are defined as plutons of more or less irregular shape with surface exposures ≥ 100 km2

A

Batholiths

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26
Q

are plutons with surface exposures ≤ 100 km2

A

Stocks

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27
Q

is a tabular, concordant pluton that parallels country rock.

A

Sill

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28
Q

is a blister-like concordant pluton characterized by a flat floor and domed roof

A

Laccolith

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29
Q

are dish-shaped to funnel-shaped concordant plutons that resemble a champagne glass in cross-section view.

A

Lopolith

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30
Q

tabular intrusions that cross-cut country rock layers.

A

Dikes

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31
Q

cylindrical plutonic dikes exposed at the surface by subsequent erosion. They represent ancient conduit pipes that funneled magma upward to a volcano that has long since been removed by erosion.

A

Neck

Volcanic Neck

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32
Q

carrot-shaped, cylindrical pipes that can extend to depths of 200 km. It develop via explosive intrusions that originate deep within the mantle. The explosiveness is due to the high volatile content which propels magma and xenolith fragments upward towards the surface.

A

Diatreme

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33
Q

Major distinctions in rock type are based on two criteria

A

Magma Chemical Composition

Environment of Magma Emplacement

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34
Q

Gas Content of

Mafic
Intermediate
Felsic

A

1-2%
3-4%
4-6%

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35
Q

Igneous rocks are classified according to (a) and (b).

(a) is determined by magma chemistry.
(b) refers to the size, shape, arrangement and degree of crystallinity of a rock’s constituent

A

Composition

Texture

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36
Q

The most straightforward approach to determining the mineralogy involves visually identifying the minerals and determining their percentages by volume

A

Modal or Mode Composition

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37
Q

systems are commonly used in aphanitic or glassy volcanic rocks, in which a rock’s modal mineral composition can not be determined

A

Normative Mineralogy

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38
Q

Weight percentage of Silica of;

Ultrabasic
Basic
Intermediate
Acidic

A

<45%
45-52%
52-66%
>66%

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39
Q

Percent of Dark Colored Minerals

Ultramafic
Mafic
Intermediate
Felsic

A

> 90%
70-90%
40-70%
<40%

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40
Q

General description of rock color based on mineral composition

Dark greenish rocks rich in olivine; may also contain pyroxene and amphibole

A

Ultramafic

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41
Q

General description of rock color based on mineral composition

Light colored or red rocks rich in potassium feldspar, quartz, biotite or muscovite

A

Felsic

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42
Q

General description of rock color based on mineral composition

Dark colored rocks containing pyroxene, amphibole, olivine, biotite

A

Mafic

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43
Q

What rock is it?

Ultramafic and Aphanitic

A

Komatiite

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44
Q

General description of rock color based on mineral composition

grayish to salt and pepper colored rocks rich in plagioclase, amphibole, biotite, quartz

A

Intermediate

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45
Q

a very dark-colored rock, depleted in SiO2 and commonly enriched in the minerals pyroxene, olivine, amphibole and plagioclase.

A

Peridotite

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46
Q

dark-colored, SiO2-poor rocks rich in plagioclase, pyroxene and olivine

A

Basalt

Gabbro

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47
Q

are gray-colored to salt and pepper-colored rocks rich in hornblende, pyroxene and plagioclase. Contain more than half to almost two-thirds SiO2.

A

Andesite and Diorite

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48
Q

are light-colored rocks, containing approximately two-thirds SiO2, rich in plagioclase, alkali feldspar and quartz and also containing small amounts of hornblende and biotite.

A

Dacite

Granodiorite

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49
Q

are light-colored rocks containing more than two-thirds SiO2 and rich in quartz, alkali feldspar with small percentages of plagioclase and biotite

A

Rhyolite

Granite

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50
Q

Magma composition of Scoria

A

Basaltic

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51
Q

contain complete crystal faces that are not impinged upon by other crystalss, developed under circumstances such as slow cooling of magma.

A

Euhedral

Idiomorphic

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52
Q

partially complete crystal form

A

Subhedral

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53
Q

Magma composition of Pumice

A

Felsic

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54
Q

lack any observable crystal faces, they have had to take the shapes of whatever open spaces were available between the already crystallized minerals

A

Anhedral

Xenomorphic

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55
Q

there is a mix of euhedral, subhedral and anhedral grains.

A

Hypidiomorphic-Granular Texture

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56
Q

wholly crystalline texture

A

Holocrystalline

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57
Q

wholly glassy textures

A

Holohyaline

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58
Q

partially crystalline/partially glass texture

A

Hypocrystalline

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59
Q

very fine-grained as a result of rapid cooling at the surface. -implies high crystal nucleation rates

A

Aphanitic texture

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60
Q

-grains are too small to be resolved optically but are visible with an electron microscope and can be identified by XRD.

A

Crypocrystalline

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61
Q

can be discerned with a petrographic microscope ; ________rocks in which elongate rectangular grains of feldspars are dominant have felty texture

A

Microcrystalline

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62
Q

(A) or coarse-grained mineral sizes that has crystal diameters ranging from 1to 30mm.

(B) 1mm to 3mm
(C) 3mm to 10mm
(D) 10mm to 30mm

A

Phaneritic

Fine grained
Medium grained
Coarse grained

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63
Q

(A) texture consist of two distinctly different size crystals. large crystals and finer grained material

(B) large crystals in the rock is called
(C) finer grained material in the is called

A

Porphyritic

Phenocrysts
Groundmass

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64
Q

characterized by large crystals averaging more than30 mm in diameter

A

Pegmatitic

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65
Q

This texture is in contrast with Pegmatitic texture, this texture refers to extremely fine grained minerals

A

Aplitic Texture

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66
Q

a porphyritic rock that contains scattered phenocrysts in a glassy matrix.

A

Vitrophyre

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67
Q

Important alteration product of divitrification

A

Palagonite

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68
Q

texture that is a product of devitrification; _______ are spherical to ellipsoidal clusters of radiating fibrous alkali feldspars and a polymorph of SiO2

A

Spherulitic Texture

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69
Q

develops by hydration of obsidian on fracture surfaces that are exposed to moisture in the atmosphere or to meteoric water (groundwater).

A

Perlitic texture

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70
Q

Texture in which minerals filled the cavities

A

Amygdaloidal Texture

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71
Q

Texture in which gas cavities filled with primary minerals

A

Miarolitic Texture

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72
Q

rocks formed at intermediate depth not clearly distinct from those of volcanic and plutonic rocks. They can have fabric similar to that of plutonic and volcanic rocks.

A

Hypabyssal Rocks

73
Q

Temperature at which a rock will first start to melt
or
temperature in which the phase is 100% solid

A

Solidus

74
Q

The main factor that determines the texture of an igneous rock is the ___________

Other factors are
a
b
c

A

Cooling Rate

Diffusion Rate
Rate of Nucleation
Crystal growth rate

75
Q

the rate at which enough of the chemical constituents of a crystal can come together in one place without dissolving

A

Rate of Nucleation

76
Q

the rate at which atoms or molecules can migrate through magma.

A

Diffusion rate

77
Q

a measure of the increase in crystal radius over time

A

Crystal Growth Rate

78
Q

Temperature at which a rock will be fully molten.
or
temperature in which crystallization starts

A

Liquidus

79
Q

is an amorphous solid. Possess a disordered form, lacking an ordered crystalline structure

A

Glass or Vitric

80
Q

occurs when melts of any composition come into contact with liquid water or air.

A

Quenching

81
Q

formed by partial crystallization of magma that contains scattered phenocrysts in a glassy matrix.

A

Vitrophyre

82
Q

produced by fragmenting processes that creates broken pieces of volcanic rock and/or mineral grains

A

Volcaniclastic

Pyroclastic

83
Q

texture contains spherical to ellipsoidal void spaces.

  • develop due to exsolution and entrapment of gas bubbles in lava as it cools and solidifies.
A

Vesicular texture

84
Q

8 most abundant elements in the earth’s crust by weight percent

A 
O-47%
Si-28%
Al-8%
Fe-5%
Ca-3.5%
Na-3%
K-2.5%
Mg-2%
85
Q

Shand Classification base %DCM

DCM- dark colored minerals

A

<30% Leucocratic
30-60% Mesocratic
60-90% Melanocratic
>90% Hypermelanic

86
Q

Is it saturated, oversaturated or undersaturated?

  1. Qtz + feldspars and/or Mg orthopyroxene
  2. Forsterite, Nepheline, Leucite and other feldspathoids + feldspar and/or orthopyroxene minerals
  3. felds and/or Mg orthopyroxene only
A

Oversaturated
Undersaturated
Saturated

87
Q

Ellis Classification of % DCM

A 
<10% Holofelsic
10-40% Felsic
40-70% Mafelsic
70-90% Mafic
>90% Ultramafic
88
Q

Aluminum abundance

1) Al2O3 > CaO + Na2O + K2O
2) Al2O3 < Na2O + K2O
3) Al2O3 = Na2O + K2O
4) Na2O + K2O < Al2O3 < CaO + Na2O + K2O

A
  1. Peraluminous
  2. Peralkaline
  3. Subaluminous
  4. Metaluminous
89
Q

are suites of rocks that form in response to similar geological conditions.

A

Petrotectonic Association

90
Q

Oceanic lithospheres’s four distinct layers;

This Layer contains well - stratified marine pelagic sediments and sedimentary rocks that accumulate on the ocean floor.

A

Layer 1 - Sediment

91
Q

Oceanic lithospheres’s four distinct layers;

This layer contains mantle peridotite is marked by high temperature, solid state strain fabric (metamorphosed) and represents the lowest layer of the oceanic lithosphere.

A

Layer 4 - Peridotite

92
Q

Oceanic lithospheres’s four distinct layers;

This layer can be subdivided into two basaltic rock layers.

a) __________
b) __________

A

Layer 2

a) Pillow basalt
b) Basalt dikes

93
Q

Mid-ocean ridge basalts can be subdivided:
a)
b)

A

N-MORB

E-MORB

94
Q

Mid-ocean ridge basalts

represent 20-30% partial melting of a well-mixed, depleted mantle source

A

N-MORB

95
Q

Mid-ocean ridge basalts

  • have higher incompatible elements
  • represent smaller degrees (10-15%) of partial melting of residual mantle rock so that the incompatible elements are more highly concentrated
A

E-MORB

96
Q 
Chemically diverse igneous assemblages erupt in the convergent margins widely distributed in 
a)
b)
c)
d)
A

Pacific Ocean
Eastern Indian Ocean
Carribean
Scotia Sea

97
Q

Oceanic lithospheres’s four distinct layers:

This layer contains massive gabbro in the upper section, layered gabbro in a middle section, and increasing amounts of layered peridotite towards the bottom of the section, marking the base of ocean crust.

A

Layer 3

98
Q

Plutonic rocks at convergent margins (7)

A 
Diorite
Granodiorite
Quartz Diorite
Granite
Gabbro
Tonalite
Trondhjemite
99
Q

Convergent Plate Boundaries

Variables in which can diversify magma composition.
5

A

1) Composition and thickness of overlying plate
2) Composition of rock experiencing anatexis
3) Flux Melting
4) Diversification Processes
a) Fractionation
b) Assimilation
c) Magma Mixing
d) Metamorphic Reactions
5) Dip angle of the subduction zone

100
Q

is the signature volcanic rock suite of convergent margins and constitutes one of the most voluminous rock assemblages on Earth, second only to MORB.

A

BADR

Basalt, Andesite, Dacite, Rhyolite

101
Q

contain 45 – 52% SiO2 and can be subdivided into a number of different varieties based upon major and minor element concentrations

A

Basalt

102
Q

Basalts common in convergent margins

A

Aphanitic & Aphanitic-Porphyritic varieties of Tholeiites

Calc-alkaline Basalts

103
Q

Basalt with higher concentrations of Al2O3, typically in concentrations greater than 16 wt %.

A

Arc tholeiites

104
Q

Basalt with higher alkali concentrations and not displaying iron enrichment typical of tholeiitic fractionation trends.

A

Calc-alkaline Basalts

105
Q

Rock with 52 – 63% SiO2.

A

Andesite

106
Q

Andesite with

1) > 52 – 57% SiO2
2) > 57 – 63% SiO2

A

1) Basaltic Andesite

2) Silicic Andesite

107
Q

Rock with 63 – 68% SiO 2, that extends to 77%

A

Dacite

108
Q

Rock with 66 – 69% SiO 2, although the lower TAS limit begins at 57% SiO 2

A

Trachyandesite also called as

Latite
Shoshonite

109
Q

Rock with >69% SiO2

A

Rhyolite

110
Q

Rock with 68 – 73% SiO2 - are associated with explosive silicic eruptions producing fragmental, glassy and aphanitic to aphantic – porphyritic textures

A

Rhyodacite

111
Q

develop on the overlying ocean lithosphere plate, above the subduction zone.

are underlain by intermediate to mafic plutonic suites dominated by diorite, quartz diorite, granodiorite, tonalite and even gabbro.

A

Island Arc

112
Q

High magnesium intermediate volcanic rocks that contain a SiO2 - saturated (52 – 68% SiO 2) groundmass

named from ______ of ________

A

Boninite

Bonin Island
Western Pacific Ocean

113
Q

This rock is silica-saturated ( >56% SiO 2 ) rocks with high Sr/Y and La/Yb ratios and low HFS (such as Nb and Ta) concentrations

This rock is named from ____ Islands of the ____

A

Adakites

Adak Island
Aleutian Island Chain

114
Q

How does backarc extension occur?

A

“Trench pull” forces move the volcanic arc towards the subduction zone resulting in the seaward movement of the trench and volcanic arc.

115
Q

are dark-colored, potassium - rich trachyandesites, commonly containing olivine and augite phenocrysts with a groundmass of labradorite plagioclase, alkali feldspar, olivine, augite and leucite.

A

Shoshonite

116
Q

Also called as Plagiogranite

A

Trondhjemite

117
Q

are fault - bounded, deformed rock sequences that mark the site of present or former convergent margins

A

Alpine Orogenic Complexes

118
Q

Zone in which the lower continental lithosphere does not subduct to great depths but essentially breaks off and underplates the overlying continental lithosphere plate producing a doubly thick lithosphere.

A

Continent-Continent Collision Zone

119
Q

is an intensely sheared, heterogeneous rock assemblage embbedded within a highly deformed mud matrix.

A

Tectonic Melange

120
Q

Magma body that consist of concentrically layered (zoned) plutons formed in convergent margin settings

A

Alaskan type intrusion

121
Q

Refers to magma generation and igneous rock suites generated within lithospheric plates

can be initiated by
Hotspot
Continental Rifts
Overthickened Continental Lithosphere

A

Intraplate Magmatism

122
Q

are volcanic landforms that rise upward above sea level

A

Ocean island

123
Q

are volcanically produced peaks below sea level

A

Seamount

124
Q

are broad flat-topped areas that result from massive outpourings of lava flowing laterally from source vents

A

Oceanic Plateau

125
Q

3 largest flood basalt events

A

Permo–Triassic Siberian traps

Triassic–Early Jurassic Central Atlantic Magmatic Province

Cretaceous–Tertiary Deccan traps

126
Q

Consist predominantly of tholeiitic basalt flows tens to a few hundreds of meters thick with minor trachyandesites, nephelinites, picrites, volcanic agglomerates and tuffs

  • recognized as one of the greatest known outpourings of lava when the ___________ basalt province was discovered
  • analogous to burying half of the contiguous United States in lava
A

Siberian Flood Basalts

127
Q

Formed during the early Jurassic

-rocks consist of tholeiitic to andesitic basalts, with rare alkaline and silicic rocks.

A

CAMP

Central Atlantic Magmatic Province

128
Q

dominated by tholeiitic basalts with minor amounts of alkalic basalts

  • famous for the beds of fossils that have been found between layers of lava
A

Deccan Trap

129
Q

What is the driving force behind the lithospheric extension that leads to the development of continental rifts?

A

Upwelling of hot plumes

Partial melting at great depths

Subduction of ocean spreading ridges

130
Q

3 of the largest layered intrusions on Earth

A

Bushveld Complex in South Africa

Skaergaard Intrusion in Greenland

Stillwater Complex in Montana

131
Q

world’s largest layered igneous intrusion

A

Bushveld Complex

132
Q

Bushveld Complex consists of four main zones

A 
Upper Zone
     -Gabbro &amp; Norite
Main Zone
     -Gabbro &amp; Anorthosite
Critical Zone
     -Anorthosite, Norite, Pyroxenite
Basal Zone
     -Orthopxn, Harzburgite, Dunite, Peridotite
133
Q

Intraplate volcanics and Shallow intrusives

A 
Komatiites 
Kimberlites 
Carbonatites 
Lamprophyres 
Lamproites 
Anorogenic (A-type) granites
134
Q

are ultrabasic volcanic rocks found almost exclusively in Archean ( > 2.5 Ga) greenstone belts

  • High in magnesium ( > 18% MgO), olivine - rich volcanic rocks, depleted in titanium and LREE.
A

Komatiite

135
Q

Texture that commonly occurs in the upper parts of komatiite flows or in the chilled margins of sills and dikes where rapid quenching produced skeletal, acicular crystals

A

Spinifex texture

136
Q

are brecciated, magnesium - rich, ultrabasic rocks that rapidly rise to Earth ’s surface via cylindrical diatremes from deep within the mantle

A

Kimberlite

137
Q

are shallow intrusive to volcanic rocks that contain > 20% CO 3 minerals such as natrolite, trona, sodic calcite, magnesite and ankerite as well as other minerals such as barite and fluorite.

A

Carbonatite

138
Q

are magnesium rich, volatile - rich, porphyritic rocks containing mafic phenocrysts such as biotite, phlogopite, amphibole, clinopyroxene and melilite.

A

Lamprophyre

139
Q

are potassium - rich, peralkaline rocks containing minerals such as leucite, sanidine, phlogopite, richterite, diopside and olivine

A

Lamproite

140
Q

are silicic plutonic rocks that are not associated with convergent margin tectonism

A

A-type granite

Anorogenic Granite

141
Q

texture refers to sodium plagioclase overgrowths on pre existing orthoclase crystals

A

Rapakivi

142
Q

A naturally occurring landform produced where lava erupts onto Earth’s surface.

A

Volcano

143
Q

Types of Lava

A

Aa

Pahoehoe

144
Q

Types of Volcano

according to morphology

A

Shield
Stratovolcano
Cinder Cone

145
Q

Produced by the accumulation of fluid basaltic lavas and exhibit the shape of a broad , slightly domed structured that resembles a warrior’s shield

  • Gently sloping, 15° or less
A

Shield

146
Q

Also called scoria cones, built from layers of volcanic cinders (ash, glassy fragments) that often start as small fissures that rapidly grow

  • Steeply sloping, 30° to 40°
A

Cinder Cone

147
Q

Also called ______ volcanoes, built from interlayered tephra and lava flows, generally products of gas-rich andesitic magma

  • Gradually sloping
  • Most dangerous and eruptive
A

Stratovolocano

Composite Volcano

148
Q

Types of Volcano

according to activity

A

Active
Potentially Active
Inactive

149
Q

Had at least one eruption during the past 10,000 years. - Locally, a volcano is active if it had a recorded eruption for the past 600 years, and has datable material since 10,000 years ago

A

Active Volcano

150
Q

Has not had an eruption for at least 10,000 years, and is not expected to erupt again in a comparable time scale of the future

A

Inactive Volcano

151
Q

Geomorphologically young volcano that is currently not erupting, but is supposed to erupt again

A

Potentially Active Volcano

152
Q

A systematic classification of volcanic eruptions based on observations during an eruption

Tephra volume (m3)  
Column height 
Eruption type 
Description 
Duration
A

VEI

Volcanic Explosivity Index

153
Q

Calmest eruption type with steady lava fountaining and the production of thin lava flows

A

Hawaiian

154
Q

Occur as a series of discrete, canon-like explosions that are short-lived, lasting for only minutes to a few hours, often with high-velocity ejections of bombs and blocks – a process of “throat clearing”

A

Vulcanian

155
Q

Large, explosive eruptions involving high-viscosity magmas of andesitic to rhyolitic composition.

These eruptive columns produce widespread dispersals of tephra which cover large areas with an even thickness of pumice and ash

A

Plinian

156
Q

The eruption of heated water and steam without magma

Often associated with hot springs, geysers, and fumaroles or solfataras

A

Phreatic

157
Q

Also called Surtseyan, produced by the interaction of magma with groundwater or surface water

Much more explosive – as the water is heated, it flashes to steam and expands explosively

A

Phreatomagmatic

158
Q

A volcanic landform that resulted from the collapse of the summit of a volcano following an explosive silica-rich eruption

A

Caldera

159
Q

Dome-shaped mass produced from squeezed-out thick lava from volcanic vents

A

Lava Dome

160
Q

Low relief volcanic craters that form by shallow explosive phreatomagmatic eruptions

A

Maar

161
Q

Broken rock particles with varying sizes produced from volcanic eruptions

A

Pyroclasts

162
Q

rock consisting of unreworked solid material of various sizes ejected from a volcanic vent

A

Pyroclastic Rock

163
Q

or tephra, are volcanic materials with varying sizes produced by volcanic eruptions

A

Pyroclastic Material

164
Q

solid or liquid ejecta with sizes greater than 64mm

A

Block and Bomb

165
Q

rock fragments with grain sizes ranging from 264mm formed from droplets of lava

A

Lapilli

166
Q

tephra that is usually glass having grain sizes lesser than 2mm

A

Ash

167
Q

a fractured surface texture formed when bombs cool

A

Breadcrust texture

168
Q

Pyroclastic fragments that fall to the ground due to gravity. Identified by having a good sorting of angular juvenile clasts.

A

Pyroclastic Fall

169
Q

Moves at speeds up to 300m/s and can reach over to a 1000°C.

Can generate Nuee Ardentes , or “glowing cloud”

Developed with poorly sorted beds with rounded clasts that can produce block - and ash flows.

A

Pyroclastic Flow

170
Q

Have low concentrations of particles mixed with gases that travels at high velocity and horizontally from the eruption site

Usually associated with phreatic and phreatomagmatic eruptions

Identified by having a “pinch and swelling” beds with moderate sorting of moderately rounded clasts

A

Pyroclastic Surge

171
Q

It is a very fluid mudflow that occurs when volcanic debris becomes saturated with water and rapidly moves down steep volcanic slopes, generally following gullies and stream valleys

A

Lahar

172
Q

these are derived directly from magma involved in the volcanic activity

A

Juvenile or Cognate Clasts

173
Q

these are rock inclusions from the vent walls or brought from the surface by lava or pyroclastic walls

A

Accidental Clasts

174
Q

It is the explosive ejection and aerial dispersal of pyroclasts of rock and magma from a volcanic vent

A

Pyroclastic process

175
Q

a result of breaking up the cooler and rigid exterior of the lava as it continuously moves that can include block-sized autoclasts

A

Autoclastic process

176
Q

It is brought by the weathering and disentigration of volcanic rocks

A

Epiclastic process

177
Q

It is group of clasts with interstitial fluid that interact and move together

A

Massive Flow Transport

178
Q

called whenclasts behaving independently in moving interstitial fluids

A

Traction

179
Q

called when fully suspended clasts in interstitial fluid

A

Suspension

Correlation 1 (17 decks)

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