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GLE 2024 (Day 2) > SEDIMENTARY PETROLOGY (BIOCHEMICAL ROCKS) > Flashcards

SEDIMENTARY PETROLOGY (BIOCHEMICAL ROCKS) Flashcards

1
Q

Boundary between high and low Mg Calcite

A

4% Mg

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2
Q

Immiscibility Gap

A

25-40% Mg

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3
Q

Dolomite Boundary

A

40-55% Mg

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4
Q

Which is more abundant high Mg or Low Mg?

A

High Mg Calcite

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5
Q

Calcite crystal system

A

Hex

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6
Q

Aragonite crystal system

A

Ortho

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7
Q

Arrange Aragonite, HiMg Calcite and LowMg Calcite in terms of stability in Meteoric Waters

A

Low Mg Calcite
High Mg Calcite
Aragonite

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8
Q

Where is Dolomite More abundant?

A

In older Rocks (Abundance decreases with younging age)

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9
Q

Organisms which have distinctly Low Mg Skeletal compositions

A

Cyanobacteria
Cocoliths (Algae)
Planktonic Foram
Rugose Corals
Tabulate Corals
Belemnites
Trilobites

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10
Q

Organisms which have distinctly High Mg Skeletal compositions

A

Rhodophyta (Red Algae)
Sponges
Alcyonarians (Anthozoan)
Decapods (Crabs)

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11
Q

Organisms which have distinctly Aragonitic Skeletal compositions

A

Chlorophyta (Green Algae)
Scleractian Corals
Bryozoans
Brachiopods
Pteropods
Cephalopods

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12
Q

Both High and Low Mg Calcite

A

Echinoderms
Ostracods
Benthic Forams

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13
Q

Both Low Calcitic and Aragonitic

A

Stromotoporoids
Bivalves
Gastropods

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14
Q

Varying of the three

A

Serpulids (Annelids)

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15
Q

Conditions for carbonate Preservation

A

1) High Carbonate Production and Preservation
2) Low Detrital Input

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16
Q

Depositional Environmets where Carbonates are favorably formed

A

1) Low Relief, Tectonically Stable Areas
(Passive Margins, Intracratonic Seas where cratons are flooded during sea level high stands)
2) Shallow areas far from Continents
(Oceanic Platforms, Oceanic Islands, Sea Mounts and Oceanic Ridges)

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17
Q

young carbonates

A

Aragonite and high Mg Calc

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18
Q

Old Carbonates

A

Dolomite and Low Mg Calc

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19
Q

Favorable conditions for Carbonate Production

A

1) Shallow Areas of Photic Zones where sunlight is abundant
2) Nutrient Rich Shallow Waters
3) High Temp, Wave Agitated,
Low CO2, highly Alkaline (Kasi pag acidic magdidissolve)

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20
Q

Marks the ocean depth at which carbonate shells sink and undergo dissolution due to acidic and cold water

A

Lysocline

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21
Q

The depth below which CaCO3 sediment do not accumulate

A

Carbonate cemponsation depth

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22
Q

When Detrital influx exceeds carbonate production what type of rocks are formed

A

Carbonate -Bearing Detrital Seds

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23
Q

Terriestrially produced Carbonate Seds

A

1) Speleothems from Groundwaters
2) Travertine (Hot) and Tufa(Ambient) found around springs
3) Carbonate Seds precipitated from lacutrine envi

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24
Q

Sand and/or gravel sized carbonate particles

A

Allochems or grains

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25
Q

Examples of Allochems

A

1) Shells and other skeletal particles
2) Spherical Ooids
3) Clasts of Carbonates - Limeclasts
4) Peloids - Smaller pellet size

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26
Q

Roughly spherical concentrically laminated Sand Size <2mm particles that possess a nucleus

A

Ooids

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27
Q

How do ooids form?

A

Accretion of CaCO3 laminae about a particle of shell fragment or sand that acts as a nucleus for precipitaitio

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28
Q

this bacteria is said to aid in the precipitation of ooids

A

Cyanophytes

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29
Q

What environments is being indicated by the presence of ooids in the deposit?

A

Shallow Marine dominated by wave and/or tidal current in a tropical to subtropical settings

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30
Q

larger than ooids usually >2mm in diameter

A

Pisoids

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31
Q

Allochem of Gravel-Size Clasts of Cohesive Carbonate sediment

A

Limeclasts

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32
Q

When clasts are said to be derived from nearby coeval deposits they are called

A

Intraclasts

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33
Q

When rarer clasts are derived from erosion of older source rocks outside the depositional area

A

Lithoclasts or Extraclasts

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34
Q

Type of limeclast consist of cemented grains rather than cohesive muds

A

Aggregates

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35
Q

Type of aggregate limeclast which consist of cemented grains such as ooids that resmeble bunches of grapes

A

Grapestone

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36
Q

Aggregate limecalsts that have a colloform coating of carbonate laminations

A

Botryoidal grains

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37
Q

Smaller sand-size carbonate grains composed of carbonate mud that resembles fecal pellets no iternal structure

A

Peloids

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38
Q

Fecal pellets

A

Excreted by sediment feeding orgaism

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39
Q

How are peloids formed

A

1) Micritization of Ooids
2) Erosion of coehsive lime muds

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40
Q

Silt and clay size carbonate particles or simply carbonate mud

A

micrite

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41
Q

Coarser Carbonate Mud

A

MicroSpar

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42
Q

Formation of Micrites

A

DIRECT (Secretion and Precipiation)
INDIRECT (Micritization and Abrasion)
1) Secretion by Chlorophyta (Green Algae)
2) Micritization of pre-existing carbonate by microbes
3) Mechanical abrasion of pre-existing carbonate grains
4) Precipitation from solution

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43
Q

Grabaur Textural Terms

A

Rudite - Gravel
Arenite - Sand
Lutite - Mud

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44
Q

Prefix used for Field Classification using hand lends and dilute HCL and staining

A

Calci (a) - Calcite
Dolo (a) - Dolomite

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45
Q

Effects of staining calcite and Dolomite with Alizarine Red-S

A

Calcite - Pink
Dolomite - No Change

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46
Q

A classification system whch emphasizes TEXTURE of carbonate rocks coming up with six major varieties of Carbonate Rocks ( the fifth classification based on inferred origin and sixth orig texture could not be recognized)

A

Dunham Classification System

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47
Q

Mudsupported Carbonate with <10% Grains

A

Mudstones

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48
Q

Mudsupported Carbonate with >10% Grains

A

Wackestones

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49
Q

Grain Supported which contained Mud Matrix (Closed System)

A

Packstones

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50
Q

Grain Supported which do not have Mud Matrix but rather have interstitial diagenetic cements

A

Grainstones

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51
Q

In Situ Carbonate Accumulation such as Reefs and Stromatolites which were ORGANICALLY Bound at the time of Accumulation

A

Boundstones

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52
Q

Subdivision of Boundstone produced by organisms that BUILD RIGID ORGANIC STRUCTURES or FRAMEWORK such as REEFs by SECRETION

A

Framestone (Reefs)

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53
Q

Boundstone produced by organism that build ORGANIC STRUCTURES such as STROMATOLITES and REEFS by BINDING and/or ENCRUSTING pre existing Carbonate Material

A

Bindstones (Stromatolites)

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54
Q

Boundstone Produced by Organism that TRAP ORGANIC CARBONATE SEDIMENT by acting as BAFFLES which hinder its movement across bed

A

Bafflestone (Bioherms)

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55
Q

Carbonate Gravel-bearing rocks with a CLAST SUPPORTED FRAMEWORK

A

Rudstone

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56
Q

Carbonate Gravel bearing rocks with a Matrix Supported Framework

A

Floatstone

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57
Q

Carbonate rocks consist of COARSELY CRYSTALLINE CaCO3 PRECIPITATED DIRECTLY FROM SOLN

A

Crystalline Carbonate

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58
Q

Rocks in Dunham which is cosidered to be excellent reservoir rock

A

Grainstones and Rudstones

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59
Q

Rocks in Dunham which is considered to be excellent trap

A

Mudstones, wacksestones, floatstones

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60
Q

Four major Grain or Allochem types according to Folks classification

A

1) Intraclasts (Limeclasts)
2) Oolite
3) Skeletal Fragments
4) Peloids (Pellets)

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61
Q

Short for microcrytsalline calcite and used to name a carbonate mud

A

Micrite

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62
Q

In folk’s classification intergranular cement which are precipitated in pore spaces between allochems during diagenesis

A

Sparry Cement or Spar

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63
Q

Folk’s Classifications depend mainly on

A

1) Percentage of Allcohems
2) Ratio of Spar and Micrite

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64
Q

Generally Micritic Carbonate rocks are deposited in

A

Periodically Calm Environments

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65
Q

Generally Sparry Carbonate rocks are deposited in

A

Agitated Environments

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66
Q

25% of Intraclasts w/ diagenetic cement

A

Intrasparite

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67
Q

25% of Intraclasts w/ Mud Matrix

A

Intramicrite

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68
Q

25% Ooids <25% Intraclasts w/ Diagenetic Cement

A

Oosparite

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69
Q

25% Ooids <25% Intraclasts w/ Mud Matrix

A

Oomicrite

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70
Q

Fossil dominated grains w/ Diagenetic Cements

A

BioSparite

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71
Q

Fossil dominated grains w/ Mud Matrix

A

BioMicrite

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72
Q

Pellet Dominate grains w/ Diagenetic Cement

A

PelSparite

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73
Q

Pellet Dominated grains w/ mud matrix

A

PelMicrite

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74
Q

Rocks composed primarily of Carbonate Mud

A

Micrite

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75
Q

Micrite that contain small spar-filled voids

A

DisMicrite

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76
Q

In Situ Carbonate Accumulations

A

Biolithite (Boundstone)

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77
Q

Three Major Textural Groups of Folks

A

1) Micrites = >2/3 Mud Matrix
2) Sparites = >2/3 Diagenetic cement
3) Poorly Washed Sparites = 1/3 spar and 1/3 micrite

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78
Q

Division of Micrites based on % Allochems

A

1) Micrite <1% Allochems
2) Allcohemical Micrite 1-10%
3) Sparse Allochemical Micrite (Wackestone)10-50%
4) Packed Allochemical Micrite (Packestone)
>50%

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79
Q

Divisions of Sparites based on sorting and roundess

A

1) Unsorted Sparite
2) Sorted Sparite
3) Rounded Sparite

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80
Q

Supratidal

A

above High Tide line

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81
Q

Intertidal (Foreshore)

A

High Tide Line - Low Tide Line (mixed high and low energy environments)

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82
Q

Subtidal Shoal (Shoreface)

A

Constantly disturbed by waves and currents

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83
Q

Subtidal (Offshore Transition)

A

periodically disturbed by storm waves

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84
Q

Subtidal (Offshore)

A

Calm

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85
Q

Barrier Reef

A

wave resistant organic accumulation that rise above the surrouding seafloow;
BANKS and MOUNDS are organic accumulations without reef properties

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86
Q

Lagoons

A

Calm, shallow water areas on landward side of rimmed platform reefs and sand shoals

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87
Q

Deep Pelagic

A

Deposits settle from suspension in offshore

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88
Q

Deep Mass Flow

A

Deposits for submarine rockfall, slides, debrie flow and turbidity currents

89
Q

An ideal model of carbonate depositonal environment with a gentle slope towards the deep sea over distances of 10-1000km and typically develops on margins of shallow subtropical seas (important na subtropical to allow carbonate accumulation)

A

Carbonate Ramps

90
Q

Develop near shelf or platform margins where nutrient rich water upwell from depth cause carbonate buildups which creates reefs, sand shoals and lagoons landward and steeply dipping forereef deposits seaward

A

Rimmed Platforms

91
Q

Carbonate depositional environments develop during marine transgressions when ocean flood large portions of the craton to form shallow seas and where carbonate show patchwork depositional pattern Wrapping up in upwarped areas and encircling susiding basins (Bull’s eye pattern

A

Epeiric Sea platform

92
Q

Develop on volcanic seamounts or platforms separated from land by a considerable distance and in which carbonate build up develops on platform margins and encloses a lagoon between them. Reefs are on the winward side of the platforms and shoals are on the leeward side of the lagoon

A

Isolated carbonate platforn

93
Q

Occur in deepwater settings below the wave base and above the CCD and are characterized by pelagic sediment deposition

A

Submerged Carbonate platform

94
Q

Local accumulations of carbonate sediment that possess significant relief above the surrounding sea floor

A

Carbonate Buildups

95
Q

Carbonate in situ builds up by organic activities

A

Bioherm or biostrome

96
Q

Bioherm which secrete skeletal materials

A

Framestone

97
Q

Bioherm which encrust or bind together

A

Bindstone

98
Q

Bioherm which traps grains or muds

A

Bafflestones

99
Q

Biostromes in which organisms have built relatively rigid, wave resistant structures over substantial periods of time

A

Reefs

100
Q

Reefs that develop adjacent to and fringe shorelines

A

Fringing Reef

101
Q

Reef that are separated from the shoreline by a lagoon

A

Barrier Reef

102
Q

Roughly Circular reefs that encloses a lagoon without major land masses

A

Atoll

103
Q

Small isolated high relief reefs

A

Pinnacle Reefs

104
Q

Small isoated low relief reefs

A

Patch Reefs

105
Q

Formerly active reefs drowned during subsidence or sea level rise

A

Submerged Reef

106
Q

opposite of Greenhouse

A

Icehouse lowered CO2

107
Q

The proportion of energy reflected back from the surface

A

Albedo

108
Q

controls of Carbonate Diagenetic Reactions

A

Pore Fluid Geochemistry
1) Alkalinity-Acidity
2) Temperature
3) Total Dissolved Solids
4) Dissolved Mg/Ca Ratios
5) Dissolved Sulfate Ions

109
Q

How can sea water be more acididc

A

Dissolved CO2

110
Q

Three Carbonate diagenetic environment with their associated pore fluid

A

1) Sea Floor - Marine Connate Waters
2) Below Land Surface - Meteoric Waters
3) Zone of Mixing - Meteoric and denser marine waters

111
Q

Non-saturated meteoric zone above the water table

A

Vadose Zone

112
Q

Saturated meteoric zone below the water table

A

Phreatic Zone

113
Q

Important source of mud generated during EODIAGENESIS by blue green endolithic microbes that inhabit carbonate sediments (ooids, skeltal particles)

A

Microbial Micritization

114
Q

porosity and permeability change during compaction

A

Decreases

115
Q

Selective dissolution at the portions of grains under maximum stress especially at grain contact

A

Pressolution

116
Q

A texture produced by extensive pressoluton which causes interpenetration of carbonate grains

A

Fitted Fabric

117
Q

Process which leaves insoluble residue of non carbonate minerals

A

Dissolution

118
Q

Insoluble residue seams that cross cut partially dissolved grains and commonly have a toothed pattern

A

Stylolites

119
Q

Thicker seams of insoluble residue that ofte anastamose to produce braided pattern

A

Dissolution seams

120
Q

Between Meteoric and Marine water which is more acidic?

A

Meteoric Water (Lower Mg/Ca ratio)

121
Q

What type of Carbonate minerals is more susceptible to dissolution by meteoric water during diagenesis?

A

Aragonite and High Mg Calcite

122
Q

Dissolution of which produces

A

Moldic Porosity

123
Q

A mineral cement mainly composed of Aragonite and High Mg calcite

A

Marine Cements

124
Q

Cement or coatings of constant thickness and characteristics of ocean floor sedimens

A

Isopachous Rim Cement

125
Q

A mineral cement exclusively composed of low Mg Calcite

A

Meteoric Cement

126
Q

A meteoric cement which involves nucleation on host grains of multple crystals that grow outward into pore spaces to produce a fringing crystals w/ straight boundaries whose size increases away from the host grains

A

Drusy calcite cement

127
Q

involves precipitation of low mg calcite that nucleates in optical continuity with a low mg calcite cement and are common on single cystal echinoderm crystal

A

Syntaxial Calcite cements

128
Q

cement which consists of a single crystal large enough to incorporate multiple grains during its growth

A

Poikiloptic Cement

129
Q

Cements in Phreatic Zones

A

Drusy Calcite (Fringing outwards)
Syntaxial Calcite (Optical Coninuity)
Poikiloptic Calcie (Massive large crystal)

130
Q

Cements which develop on grain bottoms which hang downward from the grain

A

Pendant Cement

131
Q

Cements form between grains that may resemble an hour glass

A

Meniscus Cement

132
Q

Coments in Vadose Zone (Unsaturated Zone)

A

Pendant Cement (Hanging downward grain bottom)
Meniscus Cement (In between adjacent grains like an hour glass)

133
Q

Process in carbonate rocks in which new crystals form without significant change in composition

A

Neomorphism

134
Q

Neomorphic Sparry Caclite fromed from Micrite

A

Psuedospar

135
Q

Period of Sea level transgression chracterized by high Dolomitization

A

Ordovician to Devonian
Jurassic - Cretaceous

136
Q

Formational Conditions for Dolomite

A

High Mg/Ca
Reduced SO4

137
Q

Areas with favorable conditions for PRIMARY Dolomite formation

A

Subtropics where there is evaporation and subsequent precipation of Aragonite and Gypsum
In saline lakes contaminated by High MG Grounwater (Saline lakes have sulfate reducing bacteria)

138
Q

Mechanism of dolomite formation wherein dense brines percolate downwards through carbonate sequences

A

Reflux or Evaporative Drawdown

139
Q

A type of convective mechanism which suggest deep circulation of dolomitizing fluids

A

Kohout Convection

140
Q

This is the one responsible for keeping SO4 levels at reduced conditions which favor dolomitization at subsurface diagenetic environments

A

Bacterial reduction of sulfate

141
Q

sed rocks fromed by chemical PRECIPITATION from highly saline waters (brines) that have become oversaturated with respedt to one or more dissovled solids

A

Evaporites

142
Q

Evaporites are important _______________ in petroleum systems

A

Cap rocks or seal

143
Q

how much of the sed rock record is the evaporite?

A

1%

144
Q

latitudes which satisfies climactic conditions for evaporite formation

A

10-30 deg latitude from the equator (Subtropical)

145
Q

Areas in high latitude which favors evaporite formation

A

Rainshadow Deserts

146
Q

Marine Evaporite Sequence from Sea Water Evaporation

A

least soluble to most soluble pattern

147
Q

50% water evaporated

A

Calcite

148
Q

75% water evaporated

A

Gypsum

149
Q

90% water evaporated

A

Halite

150
Q

> 96% water evaporated

A

Potassium and Magnesium Minerals

151
Q

Warm Arid shallow marine lagoons with very low relief

A

Sabkhas

152
Q

Where are sabkhas situated?

A

Transition zones between Arid Marine and non-marine environments

153
Q

Best Known Sabkhas

A

Trucial Coast, Persian Gulf

154
Q

What usually form in the intertidal to supratidal zones?

A

Carbonates and Gypsum

155
Q

sequence of Formation from upper intertidal to supratidal at the top of the water table (Landward)

A

Bladed Gypsum
Roseiform Gypsum
Nodular Gypsum (Vadose Zone)
-dehydration due to increasng temp supratidal-
replacement anhydrite
chicken wire anhydrite

156
Q

a pattern which shows the sequential precipitation of evaporites which is the function of evaporation rates, such pattern reflects INCREASED SALINITY and DECREASED subaerial water coverage as evaporation and isolation proceeds

A

Bull’s eye pattern

157
Q

When are evaporites relatively rare

A

Precambrian

158
Q

Carnellite

A

K Mg Halide

159
Q

Kainite

A

K Mg Sulfate Halide

160
Q

Polyhalite

A

Ca, Mg, K halide

161
Q

Bischofite

A

Mg Halide - Scarce

162
Q

Sylvite

A

KCl

163
Q

Langbenite

A

K Mg sulfate - Scarce

164
Q

Keiserite

A

Mg sulfate hydrated

165
Q

Lakes situated in arid environments that have seasonal filling

A

Playa Lake

166
Q

Sabkhas: Marine = ____________: Lacustrine

A

Playa Lake

167
Q

Common pattern of lacustrine evaporite deposits

A

Bulls eye

168
Q

Mineral Indicators of Lacustrine Evaporite Deposits

A

Borax
Epsomite (Mg sulfate - hyrdated)
Gaylussite (Carbonate)
Glauberite
Natron
Trona (Carbonate)
Ulexite

169
Q

Differentiate qtz, chalcedony, opal and chert

A

1) qtz is crypto-macrocyrtalline mineral
2) Chalcedony is a cryptocrystalline radial-fibrous silica variety
3) Opal is amorphous
4) Chert is a rock composed of these minerals

170
Q

Ogranisms that secrete opaline silica

A

Diatoms
Radiolaria
Silica Flaggelates

171
Q

site of deposition of silica rich deposits

A

Below cCD

172
Q

During diagenesis opaline silica shells are converted to a partially crystalline form of silci

A

Opal-CT

173
Q

Chert that is part of layered sequence

A

Bedded Chert

174
Q

Chert interstratified with mudrocks

A

Ribbon Chert

175
Q

Cherts which occur as ellipsoidal to bulbous to irregular masses less than 1m in length that tend to be elongate, parallel to and concentration In certain strat

A

Nodular chert or secondary or replacement cherts

176
Q

siliceous deposits precipitated in hot springs

A

Siliceous sinters

177
Q

Minimum iron by weight of ironstones

A

15%

178
Q

Different types of Iron Rich Sed rocks

A

1) Precambrian Iron Formations
2) Phanerozoic Iron Stonees
3) Bog Iron, Fe-Mn Nodules, Pyrite-rich Shales

179
Q

Laminated to thinly bedded iron formations of Iron bearing minerals interlayered with chert and accounts for 60% of worlds iron ores

A

Banded Iron Formations

180
Q

iron rich Serpentine

A

Greenalite

181
Q

Iron rich Chlorite

A

Stilpnomelane and Chamosite

182
Q

Iron rich Talc

A

Minnesotaite

183
Q

Common age of BIFs?

A

Archean to Paleoproterozoic

184
Q

BIFs which dominate Archean Iron rich sed rocks and tend to be faily thin (<10-100m), elonagate lenses limited lateral extents associated with ultramafic to mafic volcanic rocks which have been formed in deep marine environments

A

Algoma-type

185
Q

Iron rich fine grained rocks in the Archean BIFs

A

Femicrites

186
Q

Type of BIFs which dominated the Proterozoic and tend to be mush larger than the archean ones

A

Superior-type

187
Q

Iron sequence with ooids, pisolithsm intraclasts and pellets

A

Granular Iron Formations

188
Q

What might be the source of Archean BIFs

A

1) Iron originated from Hydrothermal Vents
2) Silica is precipitated from Acidic waters that leached continental rocks
3) Chemical stratification leads to its layering

189
Q

What might be the source of superior type BIFs?

A

Cyanophytes - Microbial induced precipitation of iron
Non microbial precipitation of silica

190
Q

Phanerozoic Iron Rich sed rocks

A

Ironstones

191
Q

Predominant minerals in iron stone

A

Geothite and Hematite

192
Q

Two peaks of Ironstone formation which corresponds to maximum global warming and Marine Transgression

A

Jurassic-Cret
Ordovician-Devonian

193
Q

Iron formation which form where acidic groundwater delivers ferrous ions into swamps and lakes where it is oxidized and precipitated as surface crusts

A

Bog Iron Deposits

194
Q

Iron formation foe\rmed under oxidizing conditions on the sea floor where iron and manganese oxides precipitate along with other base metals

A

Polyminerallic Manganese Nodules

195
Q

What’s the source of iron-rich black shales?

A

Hydrothermal precipitated chimneys aroun black smokers

196
Q

Minerals which give black smokers back color

A

Pyrite and Chalcopyrite

197
Q

Amorphous apatite

A

Collophane

198
Q

apatite of bones and teeth

A

Hydroxy-Apatite

199
Q

Apatite cryptocrystallinite

A

Fluor-Apatite

200
Q

Rare phosphate rich rocks

A

Phosphorites (50% phosphate minerals and/or 20% phosphate by wt)

201
Q

Consists primarily of plant material (Wood, leaves, mosses, grasses and phytoplanktons) that have been buried, compacted and heated and biochemically altred during diaganeses

A

Coal

202
Q

Areas of Coal Fomation

A

1)Paralic Shoreline Environments
2) River Floodiplains
3) Shores of shallow lakes, cratonic or continental rift valley settings
4) Poor Drainage Areas

203
Q

Thick dense deposits of organic material that accumulate over long periods of time

A

Peat

204
Q

Progressive transformations during coal formations driven by increasing temp and a bit of pressure increase

A

Coalification

205
Q

Why are there no coals older than Devonian?

A

Because woody plants start to inhabit land only during Devonian

206
Q

Soil orders associated with Coal

A

Histo and Verti

207
Q

Coal ranks based on progressive changes in composition, texture and appearance

A

Lignite
Sub-bituminous
Bituminous
Anthracite

208
Q

Other trends that is a function of coalification

A

1) Increasing Carbon Content
2) Gradual Color Change from Brownish to Blakish
3) Decrease Moisture and volatile content
4) Increasing hardness and compactness
5) increasing reflectivity

209
Q

Reflective organic compounds that starts to form with sub-bituminous formation

A

Vitrinite

210
Q

Low rank of Coals or soft Coals

A

Lignite and Subbituminous

211
Q

Primary use of Soft Coals

A

fuels in electric powerplants

212
Q

What can be the detrimental effects of burning soft coals?

A

production of airborne pollutants since they have high volatile content

213
Q

Compact, hard, black and somewhat reflective

A

Bituminous

214
Q

High ranking bituminous Coal

A

Coking Coal

215
Q

Whats the use of high ranking bituminous coal

A

Steel making

216
Q

Cleaning burning coalwhich is only less than 1% of the coal worldwide

A

Anthracite

217
Q

Carbon content

A

50-70
70-80
80-90
>90

218
Q

Volatile content

A

45-55
40-50
25-40
5-15

GLE 2024 (Day 2) (41 decks)

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