METAMORPHIC PETROLOGY (ZONE, FACIES, SERIES)

Question 1

Temperature of metamorphism

Answer 1

150-600

Question 2

Subdvisions of Metamorphism temperature

Answer 2

L: 150-400
M:400-600
H:>600

Question 3

Subdivisions of Metamorphic Pressyre

Answer 3

L: 0-2 Kbar = 0-6 km
M: 2-6 Kbar = 6-20 km
H: >6kbar = >20km

Question 4

3.3 Kbar is equivelent to what depth?

Answer 4

approx. 10km

Question 5

Max depth of metamorphism

Answer 5

40-50 Km

Question 6

Minerals that form within a more limited temperature and/or pressure range which effectively indicate the temp/pressure conditions of metamorphism occuring in such environment

Answer 6

Index Minerals

Question 7

Index minerals of Barrow and Tilley

Answer 7

Chlorite
Biotite
Almandine
Staurolite
Kyanite
Sillimanite

Question 8

Lines drawn on geologic maps that mark the FIRST APPREANCE of a particular index mineral

Answer 8

Isograds

Question 9

Regions bounded by two isograds of an index mineral

Answer 9

Metamorphic Zone

Question 10

This is the six metamorphic zones based on the six index mineral isograds which is a key to interpret progressive metamorphism in an evolving orgenic belt

Answer 10

Barrovian Zones

Question 11

Who first characterized Metamorphic zones

Answer 11

George Barrow and
C.E Tilley
Harker
Scotland

Question 12

Biotite forms from what minerals

Answer 12

Chlo
Musc
Qtz
Ruti
Magn

Question 13

In Almandine Zone, garnet usually occurs as?

Answer 13

Porphyroblasts

Question 14

Minerals which transform to almandine

Answer 14

Chlo and Magnetite

Question 15

Lower Temp minerals in Barrovian Zones

Answer 15

Chlorite, Biotite, Almandine

Question 16

High Temp minerals in Barrovian Zones

Answer 16

Staurolite, Kyanite, Sillimanite

Question 17

Kfelds form from the breadkdown of what mienral?

Answer 17

Muscovite

Question 18

Stauroilite forms from what minerals?

Answer 18

Almandine, Chlorite and Muscovite

Question 19

staurolite exists only in?

Answer 19

Staurolite Zone

Question 20

High Pressure aluminosilicate?

Answer 20

Kyanite (Al2SiO5 or Al AlO SiO4)

Question 21

Low Pressure aluminosilicate

Answer 21

Andalusite

Question 22

dehydration of these minerals form Kyanite

Answer 22

Staurolite and Pyrophyllite

Question 23

Marks the highest temperature zone defined by Barrow and Tilley

Answer 23

Sillimanite Zone

Question 24

High Temp Alumino silicate?

Answer 24

Sillimanite

Question 25

Sillimanite can form from dehydration of this mineral in the presence of Quartz

Answer 25

Muscovite

Question 26

Barrovian Zones are based on the observation of what kind of met rocs

Answer 26

Pelitic

Question 27

Whats the limitations of Barrovian Zones

Answer 27

Cannot be used in non-peilitic not compatible for subduction settings non compatible for contact Met Envi

Question 28

Distinctive mineral Assemblages in met rocks that form in response to a particular range of temperature and/or pressure conditions and does not imply genetic origin but assemblages closely constrains the temp and/or pressure condtitions

Answer 28

Metamorphic Facies

Question 29

Who first describe metamorphic facies?

Answer 29

Pentii Eskola, Finland

Question 30

Give the Metamorphic Facies in Increasing TandP

Answer 30

Alb-Epi Horn Hbl Horn Pyx Horn Sanidinite Horn Zeol Prehnite-Pumpelly Greensch Ampihbo Granu Blue Sch Eclogite

Question 31

The Hornfels facies are subdivided into how many subfacies?

Answer 31

four Albite-Epid Hbl, Pyx, sanidinite

Question 32

Type of met that produces hornfels

Answer 32

Heat induced in areas with igneous intrusions Contact Met or Hydrothermal Met

Question 33

Environment where hornfels usually form

Answer 33

Ocean Spreading Centers which represent hydrothermal met

Question 34

What defines a particular hornfels facies?

Answer 34

Non-foliated Texture and Index Mineral Assemblage

Question 35

In Hornblende Facies, at 450deg cel. Dolomite is replaced by this mineral

Answer 35

Diopside

Question 36

Hornfels facies record what

Answer 36

Temp driven minreal changes driven by igneous intrusions into country rock or hydrothermal metamorphism related to shallow magmatc activity

Question 37

at which depth does Contact Metmorphism predominates

Answer 37

upper 10 km

Question 38

In what TandP range does Zeolite and Prehnite-Pumpellyite form

Answer 38

Low to Mod Tand P

Question 39

What type of Metamorphism is responsible to zeolite and prehnite-pumpellyite

Answer 39

Burial Met in Sed Basins as well as at Hydro Met at Ocean Ridges, Hotspots and Volcanic Arcs

Question 40

Low temp low press met series

Answer 40

Zeolite Facies

Question 41

Hydrous Na and Ca Al tectosilicates forme by diagenetic and low temp metamorphic rections

Answer 41

Zeolites

Question 42

Possible origins of Zeolite Facies Minerals

Answer 42

1)Hydro. Alt of Volcanic Protolith 2) Devitrification of Basalat Glass and Tuff 3) Reaction of Pelite and Graywacked with Saline Water

Question 43

Where do Zeolite minerals usually occur or mode of occurrence

Answer 43

Isolated Vesicles and Veins Disseminated within met rocls

Question 44

series of alteration of Zeolite minerals in increasing T and P

Answer 44

Stilbite - Heulandite - Laumontite - Wairakite

Question 45

at what temp do zeolite minerals alter to prehnite pump

Answer 45

250deg cel 3-5km

Question 46

High temp alteration of Prehnite-Pumpellyite results in the neocrystallization of these minerals which also marks the boundary towards Albite-Epidote Hornfels Series and greenschist facies

Answer 46

Actinolite and Epidote

Question 47

High T and High P met facies are produced by

Answer 47

Dynamothermal under non-uniform stres

Question 48

Environment of formation of HiT-P met facies

Answer 48

Convergent plate

Question 49

Barrovian Zones that corresponds to Greenschist Facies with Pelitic Protolith

Answer 49

Chlotie Zone - Lower Gschist Facies Biotite Zone - Upper facies L.Almandine Zone - Uppermost

Question 50

What marks the transition from Greenschist to Amphibolite facies

Answer 50

Inc: Hbl-Gnt-Antrhopyllite Dec: Acti-Chlo-Biotite-Talc

Question 51

In what facies do staurolite appear in Pelitic rocs

Answer 51

Amphibolite

Question 52

Hypersthene Bearing Granitic Gneiss

Answer 52

Charnockite

Question 53

What separates Granulite I to granulite II

Answer 53

Presence of Hornblende and Biotite

Question 54

Pyroxenes which only appears in Granulite Facies

Answer 54

Hypersthene and Diopside

Question 55

Unusually high pressure/temperature rations reflecting existense of unsually low geothermal gradients

Answer 55

Blueschist Facies

Question 56

Line of equal temperature

Answer 56

Isotherm

Question 57

at which temp and pressurre does the Blueschist-greenschist transition facies occue

Answer 57

T: 350-450 P: 8Kbar

Question 58

Minerals occur in Eclogite Facies at pressure >25 Kbar >80Km and Temp >600 deg cel

Answer 58

Ultra High Pressure Mineral

Question 59

A high pressure polymorph of Silica

Answer 59

Coesite

Question 60

High pressure polymorph of Carbon

Answer 60

Diamond

Question 61

High Presure Garnet

Answer 61

Majorite

Question 62

Crater at which coesite was first discovered

Answer 62

Meteor (Barringer)Crater

Question 63

A sequence of facies that occurs across met terrane due to difference in PT conditions it provide key information concerning P-T-t conditions as well as Tectonic settings in which metamorphism occured

Answer 63

Metamorphic Facies Series

Question 64

Three Major Group of Facies Series

Answer 64

Group

Question 65

What kinds of rocks may be produced by low presure contact metamorphism

Answer 65

Hornfelsic and granoblastic

Question 66

First Geologists who first mapped isograd zones in Scottish Highlands

Answer 66

George Barrow