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influence the size of the electrostatic precipitator.
Aluminum, silicon, and iron
is also applied to mineral matter that may have been transported into future coal deposits (i.e., this mineral
matter was not a part of the plant substance that contributed to the coal precursor nor
was it introduced during the coalification process) by water or wind
syngenetic mineral matter
refers to that material which was deposited into the
peat bog by descending (or ascending) solutions in cracks or fissures or in the bedding
planes of the coal; such mineral matter may often be found as cleat fillings
epigenetic mineral matter
produces barriers to heat exchange in the affected
equipment, which can substantially reduce its efficiency and require costly repairs.
s (slagging or fouling)
most common minerals in coal
illite clay, pyrite, quartz, and calcite
often constitute as much as 25% of the coal mineral matter.
Sulfide minerals
may occur
in concentrations as high as 20% w/w of the total mineral matter
quartz
particular element that occurs in concentrations of less than
0.1%; <1000 ppm) in the earth’s crust are classified as t
trace elements
chalcophile elements (i.e., those elements which commonly form sulfides; such as c
cobalt,
Co; nickel, Ni; lead, Pb; and antimony, Sb)
lithophile elements
silicon, Si; titanium, Ti;
aluminum, Al; and potassium, K)
Kaolinite minerals
Kaolinite
Dickite
Nacrite
Halloysite
semctite minerals
Bentonite
Glauconite
Montmorillonite
Nontronite
Pyrophyllite
Saponite
Sauconite
Talc
Vermiculite
Illite
Muscovite
illite minerals
what are the members of pyrite?
Cattierite CoS2
Laurite RuS2
Marcasite FeS2
Pyrite FeS2
Vaesite NiS2
Villamaninite (Cu⋅Ni⋅Co⋅Fe)S2
low fusion temperature
Coal that is relatively rich in iron-bearing minerals (such as pyrite or siderite)
high fusion temperature
aluminum-bearing minerals (such
as kaolinite or illite)
The iron-bearing minerals in
ash, such as
wustite (FeO), almandite (3FeO⋅Al2O3⋅3SiO2), and fayalite (Fe2SiO4,
also called iron chrysolite
The clay minerals in coal contain water that is bound within the mineral lattice
– kaolinite contains 13% w/w bound water, illite contains 4.5% w/w bound
water, and montmorillonite contains 5% w/w bound water
elements in concentrations greater than 0.5% in the whole coal and
these normally include aluminum, calcium, iron, and silicon;
major elements,
hose in the range of concentration of about 0.02 to in the whole coal and
these usually include potassium, magnesium, sodium, and titanium, and sometimes
phosphorus, barium, strontium, boron, and others, depending on the geologic area
minor elements
all other inorganic elements usually detected in coal
at less than 0.02% (200 ppm) down to parts per billion and below
trace elements
an assay of the moisture, ash, volatile matter,
and fixed carbon determined by series of prescribed or standard test
methods developed as a simple means of determining the
distribution of products obtained when the coal sample is heated under specified
conditions.
proximate analysis of coal
is actually a misnomer insofar as the
majority of the volatile matter is the volatile product of the thermal decomposition
of coal through the application of high temperatures.
volatile matter content
consists of groundwater and
other extraneous moisture and can be evaporated
adventitious moisture,
occurs
within the pore systems of the coal and is analyzed quantitatively
inherent moisture
The mirror is used when an
externai source of monochromatic light, such as a
sodium vapor lamp
strong pleiochroism of a mineral
herapathite
the angle of incidence needed to produce the 90 degrees angle between the reflected and refracted rays is called
brewsters angle
used to adjust the intenstiy of the illumination
rheostat control
Because the light reaching the sample from the fixed condensor is only moderately converging, the illumination provided mineral is viewed perpendicular to the path of light,
orthoscopic illumination.
onsists of strongly converging light
viewed simultaneously from different angles in a cone of light using the maximum aperture
conoscopic illumination,
distance between the end of the lens
and the top of the sample
free working
distance (FWD)
size of the cone of light that the lens can accept
angular aperture (AA)
thickness of cover slip theat provides the greatest oprical efficiency
0.17 mm
distance between the lower and upper
limits of reasonably sharp focus
depth of
field.
indicates that the lens is constructed of strain-free lens
elements and is intended for use with polarized light
P
also known as one wavelength or first order
gypsum plate
quarter wavelength plate 147nm
mica plate
provided on the knobs to allow
the slide to be moved in uniform
increments and the size of the
increments can be selected by
using different knobs.
Detentes
strongly absorbs light
that vibrates parallel to its cleavage.
biotite
glass in water
1.33
carbon tetrachloride
1.52
hig relief
0.12
low relief
0.04
intermediate
0.04-0.12
involves
examining the “shadows” cast by the grains when
part of the light coming up through the microscope is
blocked
Oblique Illumination Method
the grains are dark on
the side facing the darkened part of the field of view
index of the grains is lower than the índex of the
oil
e grains are light on the side facing the darkened part of the field, t
e index of the grains is
higher than the index of the oil.
cleavages commonly found in the isometric crystal system include
cubic {001} (three at right angles), octahedral { 111}
(four cleavages that outline an octahedron), and
dodecahedral {110} (six cleavages that outline a
dodecahedron)
CV direction
that the light is traveling
propagation direction
represents the side-to-side oscillation of the electric
vector of the plane polarized light.
vibration direction
numerical value depends on the path followed by the light through the mineral
Birefringence
numerical values of birefringence
are for light whose wavelength is 589 nm
retardation is 2500 nm,
a creamy white
Retardation for all wavelengths is 500 nm. Only a portion of the
red and violet ends of the spectrum are transmitted, and
500 nm light is completely blocked. The color is perceived
first-order red.
maximum birefringence of 0.009.
Quartz
low birefringence such as
plagioclase, K-feldspar, gypsum,
The angle between the length or
cleavage of a mineral and the mineral’s vibration
directions is a diagnostic property called
extinction angle
extinction in a grain follows an irregular or wavy
pattern it is called
undulatory extinction.
The
mica plate produces
147 nm of retardation,
light propagating at righ tangles to the optic axis
maximum birefringence
Useful for determining
privileged vibration
directions of any light
ray from path and
optic axes
Vibration directions
bisect angle of planes
as shown
biot-fresnel
Useful for determining
privileged vibration
directions of any light
ray from path and
optic axes
Vibration directions
bisect angle of planes
as shown The value is plotted on the left side of the diagram. NA is the
numerical aperture of the objective lens, 2D is the
distance between the melatopes, and 2R is the diameter of the field of view
Tobi’s Method
Mallard’s method for determining 2V uses an acute
bisectrix figure. It depends on the observation that
the melatopes must be further apart for larger values
of 2V (and 2E). If 2V is small, the melatopes are
dose together, and if 2 V is larger, the mela topes are
further apart.
Mallard’s Method
n updated version of the
Michel-Lévy method and is used when 2 V is large
and the melatopes are outside of the field of view. It
involves measuring the angle of stage rotation
needed to cause the cross-shaped isogyre in the
acute bisectrix figure to split apart and leave the field
of view. It also may be used with modera te accuracy
for obtuse bisectrix figures and is the basis for distinguishing between obtuse and acute bisectrix figures when 2V is large.
Kamb’s Method
method is used with optic axis
interference figures and depends on the observation
that curvature of the isogyre in a 45º position is a function of 2 V (Figure 7. 32) ~ If 2 V is 90º, the isogyre
forms a straight line in a 45º position. For smaller
values of 2V, the isogyres are progressively more
curved. If 2V is less than about 30º, both melatopes
are usually in the field of view. For 2V of less than
5º, the distance between the mela topes is very small
and the two isogyres look almost like the uniaxial
cross except for the small gap right in the middle.
Wright Method
unusual form of dispersion called that is found in brookite
crossed axial
plane dispersion
produced when
the obtuse bisectrix is parallel to the b axis.
Horizontal or parallel dispersion
acute bisectrix is parallel to the b axis
Crossed bisectrix dispersion
what is the mineral alteration of cordierite
pinite
mineral alteration of olivine
iddingsite
what is xenotime
igneous rock
found in meteorites, has a composition dose to the
ideal FeS and is hexagonal.
Troilite
H = 3t-4!; G = 4.6;
pyrrhotite
opaque amorphous titanium
oxide
Leucoxene
metamorphosed bauxite deposits
emery
e members of the spinel group
spinel,
magnetite, and chromite series
inverse spinel
structure with ali of the larger divalent cations (A2+)
in octahedral sites and half of the trivalent cations
(B3+) in octahedral sites and half in tetrahedral
sites.
magnetite
Spinel Series
Spinel MgA120 4
Hercynite FeAl20 4
Gahnite ZnA120 4
Galaxite MnA12 0 4
Magnetite Series
Magnetite FeFe2Ü4
Magnesioferrite MgFe20 4
Ulvõspinel FeFeTi04
Franklinite ZnFe2 0 4
Jacobsite MnFe20 4
Trevo ri te NiFe2 0 4
Chromite Series
chromite~ FeCr20 4
Magnesiochromite MgCr20 4
green to blue-green spinel
Pleonaste:
olive brown to brown soinel
Picotite:
Spihel: colorless, green, blue, red
Hercynite: dark green
Gahnite: blue-green, yellow, brown
Galaxite: red-brown, black
Fibrous
brucite is called
hemalite
found in
marble, resulting from the alteration of periclase.
Brucite
found as a gangue
mineral in hydrothermal sulfide deposits
magnesite
complete solid solution series with magnesite (MgC03) and rhodochrosite (MnC03)
siderite hardness 4 - 4 in a half
H = ~; G = 3.96 (pure)
altered to goethite or
less commonly to hematite or magnetite
y found in fractures and amygdules in basalt, diabase, and andesite.
sideite
a dolomite group mineral intermediat~ between
rhodochrosite and calcite.
Ca. Kutnohorite
Does n”ot readily react in cold dilute HCI, but reacts
with effervescence when powdered or if the acid is
hot.
Rhodochrosite
float in diodomethane
aragonite
dehydrate to
a crumbly mass of tinalcotine on exposure to air
borax
Minerais found in evaporite deposits
kernite-monoclinic
ulexite-triclinic
trona-monoclinic
nahcolite-monoclinic
thenardite-orthorhombic
glauberite-monoclinic
carnalite-orthorhombic
ployhalite-triclinic
kieserite-monoclinc
tinalconite-trigonal
soda niter-trigonal
Carbonate-bearing apatite is
called carbonate-apatite, or r OH-rich varieties and
dahllite
F-rich varieties
francolite
term given to
fine-grained cryptocrystalline material that contains
a substantial amount of apatite.
Collophane
fine-grained reddishor yellowish-brown material that consists of goethite, clay, chlorite, quartz, tale, a
lddingsite
essentially isotropic material
that is usually orangish or greenish. lt also is a mixture and appears to be composed of limonite and
chlorite or serpentine with other low birefringence
silicates.
Chlorophaeite
Magnesium-rich olivine often alters to serpentine,
which may either be
chrysotile or antigorite
sarne structure
as the other garnets except that a Si4+ has been
replaced by 4H+ with the hydrogens bonded to each
of the four oxygens surrounding the vacant tetrahedral site
Hydrogrossular
which ali of the silicon has been replaced by hydrogen, has been
synthesized.
Hibschite
Most andalusite is relatively pure Al2Si05 ,
although a significant amount of Mn3+ and Fe3+
may substitute for the octahedral aluminum, and
extensive solid solution to
kanonaite
used for andalusite containing substantial amounts of both Fe3+
and Mn3+.
viridine
y occurs as
slender prismatic crystals or as fine fibrous crystals
called
forms radiating,
swirled, or matied aggregates.
Fibrolite
restricted
to very high temperature porcellainite homfels in
· the contact zone adjacent to mafic intrusions or in
pelitic inclusions (buchites) in those rocks.
Mullite
common mineral in
medium- and high-grade mica schist, gneiss, hornfels, and related rocks
: Sillimanite
FOR CHLORITOID Mg2 + and Mn2 + may replace up to about 68 percent and 50 percent of the Fe2+ respectively,
although most is relatively iron rich. The manganese-rich variety is called
ottrelite
green biotite
stilpnomelane
biaxial positive and is usually pleochroic in shades of red
and yellow. F
Piemontite
found in granitic pegmatites, aplites, quartz veins, and in quartz- and
feldspar-bearing rocks that have been hydrothermally altered. It also may be found in medium- and
high-grade gneiss, quartzite, granitic gneiss, and
pelitic schist associated with other aluminous minerais such as kyanite, sillimanite, cordierite, and andalusite.
Dumortierite
melilite The common alteration is to a brown
fibrous material called
cebollite
variety that
has up to 2 percent of the octahedral sites occupied
by Mn 3 + and is analogous to piemontite in the
monoclinic series of the epidote group.
tHulite
zoisite variety that
has up to 2 percent of the octahedral sites occupied
by Mn 3 + and is analogous to piemontite in the
monoclinic series of the epidote group.
saussurite
Samples
containing significant amounts of AI and Fe3+ are
called
f assaite,
Ti bearing samples are called
titanaugite.
n, there appears to be complete solid solution between hedenbergite-rich
compositions and
johannsenite
hornblende here includes members of the following
series:
Magnesio-hornblende-ferro-hornblende
Ca2(Mg,Fe2+)4Al(ShA1022)(0H)z
Tschermakite-ferro-tschermakite
Caz(Mg,Fe2+hFe3+ 2Si6Alz022(0H)z
Edenite-ferro-edenite
NaCa2(Mg,Fe2+)sSi7Al022(0H)z
Pargasite-ferro-pargasite
NaCa2(Mg,Fe2+)4AlSi6Al20 22(0H)z
Hastingsite-magnesio-hastingsite
NaCa2(Mg,Fe2+)4Fe3+Si6A}z022(0H)z
[Na(Na,Ca)(Mg,Fe2+ ,Fe3+ Al)5Si7Al0zz(OH)z] is a
sodic-calcic amphibole with similar color and
pleochroism that is found in relatively mafic alkalic
intrusives associated with acmite, aegirine-augite,
riebeckite, or arfvedsonite.
Katophorite
converted to fine-grained, light-colored
amphibole)
uralitized
[(Mn,Fe)Si03]
is a closely related mineral with higher birefringence
and smaller 2V. Bustamite is optically negative with
2 Vx less than 60
Pyroxmangite
complex day mineral constructed of amphibolelike
double chains of tetrahedra aligned parallel to the e
axis. typically
fibrous, rather than scaly like the other day minerais, and may form flexible matted sheets that are
sometimes called mountain leather. It is monodinic
with; B = 96º, or orthorhombic, and the indicatrix is
oriented so that Z = e; thus, fibers are length slow mistaken for serpentine.
Palygorskite
similar mineral constructed of
tripie chains’ of tetrahedra.
Sepiolite
monodinic ( L
B = 90º) and have optical properties that fali in the
range no. = 1.48-1.61, n13 = 1.49-1.63, ny =
1.50–1.64; ô= 0.01-0.04; 2Vx =
Montmorillonite
formed in veins and cavities in altered
or weathered carbonate rocks and mafic igneous
rocks. They may also be found in deposits from
saline lakes
Palygorskite
found as a vesicle
filling in basalts and related volcanic rocks
Celadonite
tetrahedral sheets are continuous, but
periodically there is a reversai in the direction that
the apical oxygens face and the side on which the
octahedral sheet is mated. more or less micaceous
and may form foliated or scaly masses.
antigorite
the pattern of tetrahedra in the T sheet is distorted
to allow a match to be achieved with the O sheet
very fine-grained and may form an
irregular net-like pattern with uneven or undulatory
extinction.
lizardite
[Fe3Si20 5(0H)4] is a related
mineral with a somewhat more complex structure,
which occurs in weakly metamorphosed iron formations
Greenalite
[Fe3Si40 10(0H)z] is a
related mineral with a somewhat more complex
structure found in metamorphic iron formations.
Minnesotaite
a name given to varieties with significant Mg and
Fe2+. ln most cases, some of the OH is replaced by
F, or, to a lesser extent, Cl.
Phengite
a name given to
very fine, ragged grains and aggregates of white
mica-usually muscovite or phengite-produced by
the alteration of feldspars or other minerais.
sericite
e contains
up to 10 or 15 percent AI3+ which is balanced by replacing additional Si4+ by Al3+ in the tetrahedral sites
or by replacing (OH,F)- with 0 2 -. Fe3+ also isCQmmon and is usually balanced by replacing (OH,F)-
with 0 2 -. S
Siderophyllite
The primary compositional
variation in biotite is in the occupancy of the octa-
.hedral sites, and most biotite falls between
phlogopite* [K2Mg3AISi30 10(0H,Fh] and annite
oxygén in the hydroxyl ·sites are called
oxybiotite.
variety found in
metamorphosed iron formations th~t has substantial
Fe3+ in tetrahedral sites.
Ferriannite
[K(Fe2
+ 1_0 .5Li1-i.sAl)(Si3-3.sA11-o.s)
0 10(0H,F)z] is a closely related mineral that is colorless to light brown in thin section and resembles
phlogopite but is found in Li-bearing pegmatites
which almost never contain phlogopite
Zinnwaldite
used for certain varieties of trioctahedral brittle micas but the distinction between
clintonite and xanthophyllite is poorly defined. The
term clintonite is preferred for ali species.
xanthophyllite
used for the Mg end of this series chlorite
clinochlore
Fe end
chamosite
applied to á large group of minerais whose· structure
consists of alternating T-0-T layers equivalent to
tale layers [Mg3Si4 0 10(0Hh] and octahedral interlayers equivalent to brucite sheets [Mg3 (0H)6].
chlorite
chlorite
clinochlore, pennine, prochlorite, and
chamosite. Others include sheridanite, ripidolite,
brunsvigite, diabantite, thuringite, corundophilite,
daphnite, diabantite, strigovite, klementite, delessite,
pseudothuringite, aphrosiderite, bavalite, and helminthe.
an alteration
product after plagioclase, or occasionally amphiboles and pyroxenes, may contain prehnite as well.as
albite and an epidote group mineral.
Sausserite
fine vermicular intergrowth of quartz and plagioclase usually found at contacts b~tween K-feldspar and plagioclase is called
myrmekite
intergrowths of quartz and feldspar in interstices in
volcanic and intrusive rocks is called
granophyre.
fibrous variety of cristobalite
lussatite
yellowish brown, brown, or greenish material produced by hydrating basaltic glass.
palagonite
light-colored equivalent produc~d by
hydrating rhyolitic glass.
perlite
barium feldspar
celsian
Piutonic rocks typically contain low
piagioclase and/or K-feidspar, whiie vokanic rocks
usually contain high piagioclase and/or alkaii-feldspar. HypabyssaI intrusives
e feidspars with
iI~termediate degrees of order.
intergrowths are found for bulk compositions between about An2 and An16,
and usually consist of alternating lamellae of An0
and An25 compositions.
Peristerite
found in the bulk composition range of about An47
to An58 , and apparently consists of lamellae of
- An45 and - An60
B0ggild intergrowths
occur
for bulk compositions of about An67 to An9ci, and
apparently consist of lamellae of - An67 and - An95 .
Huttenlocher intergrowths
term given to sodic
plagioclase with exsolution blebs or lamellae of Kfeldspar.
antiperthite
albite contains alternating twin
lamellae somewhat like the pattern of squares on a
chessboard, except the units tend to be elongate and
lath shaped rather than square. It is interpreted to
be produced by replacing K-feldspar or more calcic
plagioclase with albite.
“Chessboard”
Exsolution blebs ·and lamellae of albite in microcline or orthoclase.
Perthite:
Exsolution blebs or lamellae of K~feldspar
in sodic plagioclase.
Antiperthite
Submicroscopic exsolution lamellae of
one alkali feldspar in another
Cryptoperthite
rims of sodic plag around a phenoccryst of k felds
rapakivi
rims of k felds on crystals of plagioclase
antirapakivi
intergrowth of qtz and feldspar that occurs in interstices between grains in shallow intrusive rocks usually of granitic compostion the qtz forms small vermicular grains or blbs may from a cuniform pattern
granophyre`
Intergrowth of quartz in Kfeldspar crystals. The quartz forms stnall, more or less
angular (i.e., cuniform) grains that are usually optically continuous over the entire K-feldspar crystal.
Common in pegmatites and granitic rocks.
Graphic and Micrographic
intergrowth of plag and qtz often found at k felds plag contacts
myrmekite
Sol-occupies half
of the anion sites, with the remainder vacant, and
more Ca may be present than in sodalite.
nosean
differs from nosean in that it contains substantial Ca,
which is balanced by filling more of the anion sites
with Sol-
hauyne
variety of sodalite containing significant amounts of s2 - substituting for
o-,
hackmanite
considered a variety of
haüyne containing substantial amounts of. c1- and
s2 - instead of sol-
lazurite
marialite
dipyre
mizzonite\
meionite
0.20
20-50
50-80
80-100
partially
dehydrated variety that éontains 3!H20, rather than
4H20. Dehydration may occur on exposure to air.
Leonhardite
fine-grained greenish or yellowish aggregate of chlorite, muscovite, and other silicates.
pinite
most of the crystals are anhedral
allotriomorphic
crystals are subhedral
hypidiomorphic
euhedral
pandiomorphic
curved partially concentric cracks due to shrinkage of the cooling glass
perlitic structure
refers to a amass of sanidine laths in subparallel alignments like a school of minnows
trachytic structure
phenocrysts are gathered in clusters
glomeroporphyritic
describes a situation where there is a continuous range in grain size of one or more mineral species from that of phenocrysts to groundmass size, and in which crystals of progressively smaller sizes are increasingly numerous.
seriate texture
submarine volcanism produced lavas mafic ang sodarich basaltic types in wc lava exhibits the appearance of a pile of small ellipsoidal or pillow masses
spilite
constructed by fissure eruptions
DECCAN plateau of western india
11k ft above sea level base 30 mi in dimater
mount etna of sicily
vent in colorado
cripple creek
other term of subhedral granular
granitoid
surrounded by a belt marked by intricate swriling of foliation planes structureless core of many plutonic bodies
colville granodiorite batholith of washington state
due to shrinkage during freezing of the magma granites sparsely scattered angular cavities
miarolitic
hazy ill defined dark streaks in grnitic rocks result from incomplete mixing of assimilated fragemtns of foreign origin some may result of segregation and late movement of the magma
schlieren
relic inclusions in a crystalline rock
skialith metamorphic
occur as ball like segregations consisting of concentric shells of different mineral compostion and texture
orbicles
examples of parallel dike systems
teanaway dike swarm of central washington
argyll mull inverness of west scotland
examples of radial dike swarms found in
cheviot hills scotland the crazy mountains montana and spanish peak colorado
thick sheet showing gravity stratification
wichita mountains igneous complex
curved lenticular masses injected along and concordant with arches and troughs of folded strata
phacoliths (lens rocks)
saddle shaped laccoliths
consequence of folding
lopolith
duluth lopolith in minnesota
sudbury intrusion in ontario
bushveld complex south africa
al2o3>na2o+k2o+cao muscovite biotite corundum topaz tourmaline or fe-mn garnet highly siliceous plutonic rocks
peraluminian rocks
na2o+k2o<al2o3<na2o+k2o+cao hornblende epidote or melilite formed at low temp in the presence of water
metaluminian rocks
epheline syenite pegmatites amphibole
barkevikite
based on known principles of miernal crytsallization in magmas
norm
actual mineral composition of a rock expressed in weight or in volume percentage
mode
relating to a fine-grained igneous rock usually formed at a moderate distance below the surface.
hypbassal
holocrystalline
paneuhedral
fAVORED BY higher pressure or lower temperature
microcline orthoclase perthite muscovite and cancrinite or pairs such as nepheline-orthiclase and augite-hypersthene
less than 30% mafics
leucocratic
30-60% mafics
mesocratic
60-90%
melanocratic
more than 90%
hypermelanic rocks
index less than 10
holofelsic
10-40
felsic
40-70
mafelsic
higher than 70
mafic
what type of essential mineral is found in trachyte
sanidine
feldspar are alkalic quartz is 10%
plutonic
quartz is less than 10%
syenite rather granite
rare volatile elements
lepidolite spodumene tourmaline amblygonite beryl topaz
sugary saccharoidal equigranular fine to medium grained contain mafic minerals
aplitic texture
glassy rhyloites with a pithclike rather than glassy luster
pitchstones
devritified glass with concentric or perlitic cracks and pearl luster
perlite
ranular composed of feldspars but without feldspathoids rock is intermediated or mafic
syenite diorite gabbro or anorthosite
presence of these minerals indicates andesite since these are assoc with sodic plag
hornblende biotite
rocks that compose the high Sierra Nevada of California
granodiorite
alkalic felds and plag occur in equal amounts also called qtz monzonite
adamellite
graphic granites and granophyres are charac texture is
cuneiform intergrowth of quartz and alkalic feldspar microcline perthite, microcline, or orthocalse
in granites, phenocrysts if alkalic felds are encased by mantles of sodic plagiolcase result from simultaneous crystallization of alkalic feldspar and sodic plag influence of volatiles
rapakivi texture
volatile action
pneumatolysis
these minerals are most common in highly siliceous granites altered by volatile action an in aplites and pegmatites
muscovite and lithian micas
anorthoclase is present in sodic amphiboles such as
hastingsite riebevkite arfvedsonite
contains abundant mircoperthite and sodic orthoclase
conway granite of new hamshire
granites contain biotite accom by hornblende or augite
metaluminian granites
granites contain micas
peraluminian granites
minerals are ortho and clinopyroxenes and small amount 0olivine silicic end member of charnockite series
subaluminian
charac nby amphibole pyroxene rich in soda and iron much anorthoclase and sodic plag
peralkalic granites
wichita mountains and quincy granite are examples
coarse aegirite-riebeckite granite of the atlantic island rockall known as
rockallite
well known riebeckite microgranite represents the fine grained type texture resembles rhyolites
paisanite
later formation larger crystals embedded on grains of feldspars and qtz
formed at the expense of feldspar
tourmaline
sunburst of tourmaline
aggregate made up of tourmaline and quartz
schorl rock
process of alteration due to the action of volatiles occur near the margins of granite plutons and they form bands or vein like bodies
greisening
KLiFeAlO₁₀(OH, F)₂, potassium lithium iron aluminium silicate hydroxide fluoride is a silicate mineral in the mica group
zinnwaldite
largest plutonic body in the world
coast range batholith of british columbia
convert carbonates to silicates
diopside wollastonite grossulariote
granite with few or no mafic minerlas
alaskite
intrusive igneous rock found in few places in the world. It is unique in having low silica, feldspathoid minerals, and large blocky crystals of black augite.
Shonkinite
dislodgment of comparatively small pieces of the roof rock either singly or in one or more showers called
piecemeal stoping
differs from piecemeal stoping only in the size of the blocks
cauldron subsidence
may produce either a ring dike or a stock depending upon the amount of sinking of the central block and upon the depth of erosion
underground cauldron subsidence
forceful injection of magmas
hans cloos
other term for metasomatic replacement a group of processes whereby solid rocks are changed into rocks of granitic composition and texture w/o passing through a magmatic stage
granitization
convert pure quartz to granite
potash, laumina, soda, lesser amounts of lime iron and magnesia
convert slate into grantie
remove alumina magnesia iron and water and add silica potash and soda
amphibolite
hornblende-feldspar meta rock
inyo batholith of california nevada mesozoic age roof of facies of a major batholith developed in place by recrystallization and replacement of both sed and igneous rocks
pellisier granite facies
vague remnant of country rock in granite, obscured by the process of granitization.
skialiths
metasomatic replacement that may take place during a period of deformationd is calle?
syntectonic granitization also called synorogenic or synkinematic granitization
replacement that occurs w/o any cintemporaneous deformation
static granitization
taken as extending from the surface to a depth of 4 mi. epth commonly of 4 mi with occasional extnsion to 6 mi seems a reasonable estimate for the base of the and the tmep is 250
epizone
temp of mesozone
250-350 top og 500 base 600-700 apil na guro nis katazone
late cretaceous southern california batholith plutons of tertiary age
epizone
late jurassic and early cretaceous
mesozone
earlier members of the largest batholiths
katazone
phenocrysts of plagiolcase are in excess of quartz are in excess of quartz the rock is
dacite
phenocrysts are of quartz and orthoclase the rocks is refers to the frequent occurrence of flow banded or floe structure of these rocks
rhyolite
