1. Geology
Geology = Earth Science
What is the meaning of geology ?
Geology is the study of Earth, includes, Chemical and Physical
Properties, Earth Creation, Inner and Outer Processes Affected it,
Since Its Creation To Present Day.
Geological Branches
A-Basic geology:1- Crystallography .
B-Connected Branches:1- Geochemistry.
C- Applied Geology:1-Economic Geology.
2- Mineralogy.
2- Geophysics.
2-Engineering Geology.
3- Petrology .
3-Geomorpholpgy.
3-Petroleum Geology.
4- Paleontology .
4-Structural Geology.
4-Hydrogeology.
5- Stratigraphy .
5-Photogeology.
5-Mining geology.
6- Dynamic geology .
6-Oceanography.
6-Agricultural geology.
7- Historical geology .
7- Field geology. 22
7-Miltary geology.
8-Glacial geology.
9-Volcanology.
10-Cosmic geology.
11-Geodesy.
The relationship between geology and other sciences
1-Physics ----------- Geophysics ---------- 1-Gravity Method.
2-Magnetic Method.
3-Seismology.
4-Electrical Method.
2-Biology --------------- Paleontology ------Remaining of Animals and Botanical.
3- Chemistry ----------- Geochemistry.
4-Engineering ---------- Engineering geology.
2
History of Geology
1-Humorous 600 B C :-He put an idea about the shape of Earth and he descript the earth as a disc surround by water.
2-Aresto 384-322 B C :-He is provided that the Earth is a ball by scientific method . by observation he is noticed that, the matter
collection is to the same center .
3-Herodotus 424-484 B C:-The first scientist who noticed the remaining of Botany and Animals on the mountains of earth crust ,
which is prove that the present mountains were oceans surfaces in the deep past..
4-Khalelo 1546-1642 C :- He is Provided the motion of earth around its axis is from west to east .
5-William Smith 1769-1839 C :-He is the first scientist whose established stratigraphy and correlation by its contents of fossils and
he was drawing a geological map for e England in 1845 .
History of geology- Arab scientists
1-Ibin Siena died 1049 :-The first one who is established the geology and studied also the minerals .
2-Al Bairony died 1271 :-He is described an expensive crystals minerals in scientific methods .
3-Alrazi died 1369 :-He is divided the minerals into six groups in his book (secrets of the secrets) .
Other scientist such as Jahith Takishkhandy Sarkhasy et .
3
The site of Earth within Galaxy (Milky Way)
D = Day
Y = Year
4
4
Hypothesis of Earth Creation and Global System
1-Buffoon Ht 1707-1788 (France) :-The first scientist, which is put an idea for the source of earth in his book, (The Natural History).
The idea is the present global system results from very hard attack between the sun and one of big solar mass, then many big
masses are separated and swimming in Space to different distances around the sun controlled by Sun gravity.
2-Kants Ht 1755 (German) :-This hypothesis proposed that the whole solar system was consist of very much of small solid parts swimming in the
global system in high speed. This parts were collected together by gravity with high heating due to attachment between it, which result very
hot gases (NEBULA) rotated around together in great speed. This conditions gives a hot gas rings and by the, out of center force forming ou
Sun system.
3-Nebular or Lab Lass Ht 1796 France:-The solar system in the beginning ( NEBULA) was occupied about four sizes of the solar
system. With time, there are heating loss ,contraction which results rotation with high speed around (NEBULA) axis .at same
time the out of center force makes a cycle with irregular out line which results a big masses named the solar system. later
the contraction of masses with continuous cooling and rotation makeup the solar system.
4-Other hypothesis:-
a-Planetesimal hypothesis (Chamberlin- and Moulton American- Geologist 1905).
b-Gaseous Tidal Ht (Jemis and Jeffery 1929).
New theories in origin of solar system
1-The Nuclear Explosions Theory 1931:-This Theory suggests that, a part of Global Space is composed of Dense Gases (Protogalaxy). With time
these gases collects together to form ( Nuclear Cells). So at same time Great explosions is happened for global bodies which is separated i
faraway from its original space to form (Global Galaxy). After that the Gases are began cooling with space reduction and rotation, then
finally a new birth for solar Galaxy in space, before about 10-13 Billion years ,while Gases condensation is create about 250 million years
ago.
2-Great Gas Cloud Theory 1942 -1948:-In the beginning the Sun and Stars were as Global cloud consist of Gases and dust. it is condensed by
stars light pressure, dust and gases gravity forces. This conditions lead to create rotation state to form (Primary Nuclei), The remanen
clouds stays in the center forming the Sun. Later this theory considered the Electromagnetic force is played as important agent in globa
system.
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5
Earth Creation
Since 6 Billions years , the Earth was separated from Sun. So by rotation , continuous cooling ,the mass of gas
became Ball-shape covered by solid crust called (Earth crust ), while the inner of Earth still in Fusion state.
There are four stages at Earth Creation:1-Anhydric Period:-In this period the elements consists Earth differentiated into three zones ( Gases and liquids Earth crust, Mantle
and Core) depend on gravity, rotate around Earth,( mass of gases and liquids are the outer shall) as :a-Gases and Liquids zone.
b-Silicate-Sulfides zone--------Outer part (Earth crust).
c-Iron- Nickel zone-------------Inner part (Mantle and core).
-The cooling time of Earth crust is take about 900-1000 million years.
. 2-Oceanic Period( water Basins):-This period of Rains fall is due to the critical Temperature of water, which is form water
Vapor, then Rainfall within about 300- 400 million years.
3-Contraction Period:- A big water Basins such as oceans seas are the result of continuous cooling for earth crust, association
with mountains building within about 1000 -1700 million years.
4-Continintal Drift period:- There are many evidence says that, the Dry parts of earth (Crust) was connect in the ancient time.
Then by Earth Dynamic (Hypogene Processes) the crust moves along the fusion zone of Earth (upper
part of mantle-Asthenosphere) which is result sedimentary basins due to the big Oceanic sediment.
Conclusions:a-The Earth crust and air cover were buildup at first stage.
b-The water cover was buildup at second stage.
c-The ancients evidence of life is before 2500 million years.
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Nature of Earth
A-Dimensions of Earth :1-The polar Radius =6357 kilometre .
2-Equator Radius =6378 kilometre .
3-Polar Circumference = 6357 km x 2 x 22 ÷ 7 = 40 009 kilometre .
4-Equator Circumference = 6378 km x 2 x 22 ÷ 7 = 40 077 kilometre .
5-Area of earth surface = 510 000 000 square kilometre.
7-Dry area of earth surface = 29,22% = 149 000 000 square kilometre.
8-Water area of earth surface = 70.78% = 361 000 000 square kilometre.
9-highest point of dry area at earth surface = 8848 metre (Everest mountains crest).
10-Avverage of earth surface = 840 metre.
11-deeper point of ocean = 11033 metre (Mariana trench).
12-Average of ocean deep = 3808 metre.
Polar Dimension
Equator
7
7
C
R
O
S
S
S
E
C
T
I
O
sial
5 - 60 km Crust
5 - 60 km
sail
Crust
0C
Sima
Sima
870 C
Upper Mantle
Conrad Discontinuity
Conrad Discontinuity
Peridotite Rocks
Moho Discontinuity
Moho Discontinuity
Peridotite Rocks
Mantle
35 - 2900 km
Mantle
Lower Mantle
Pallasite
Rocks
(peridotite=Fe
) ()
Gutenberg Discontinuity
2 200 C
Gutenberg Discontinuity
2900 km
Upper Core
Upper Core
Fe = 90%
Ni = 10%
N
I
N
E
A
R
T
H
2900 - 6370 km
Core
Earth Crust Density= 2.85 gm/cm3
Lowe Core
Core
Iron+Ni
Lower
Core
Mantle Density = 4.53 gm/cm3
Core Density= 10.7gm /cm3
6370 km
6 000 C
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Earth Covers
1-Atmosphere cover.
3-Biosphere cover.
2-Hydrosphere cover.
4-Lithosphere cover.
1-Atmosphere cover :-It is Air cover, surrounding Earth. Its thickness about 316 km . atmosphere is consist of many Gases like :a- N2
about
78%
b- O2
about
21%
c- Ar
about
0.93
d- CO2 about
0.03%
e- H2
about
0.011
99.124%
About 35 PPM are inactive Gasses such as Neon, Helium and Ozone are present in Atmosphere .
1-Atmosphere Cover:-Atmosphere cover is divided into:A-Troposphere layer :1- Elevation of Troposphere layer is about 8 - 18 km .
2- Temperature is decreasing about 6 ْC every 1 km
rising
3-This layer is consist of homogenous gases, water
vapour, CO2 and dust.
B-stratosphere layer :1- The second layer with elevation about 50- 80 km .
2- The lower part of this Layer is (50 km) named
Ozone layer .
3- Stratosphere temperature is increase to 35 ْC with
no storm.
4- Stratospheric Pressure is 0.5 mm mercury (1/1520) of
Normal Pressure.
C-Ionosphere Layer:1- The elevation is about 80 – 316 km
2- the Ionization is due to the affects of the Cosmic and Ultra violent
Rays, so it is good Conductor for Electricity.
3- Many of (Meteors and Meteorites)are Burn with Traffic in this Layer.
4- This Layer is Good medium to cross Radio and Wireless Waves.
D-Exosphere layer :The highest layer in the Atmosphere ,so it is extend as far as entrance of outer
space .
Meteor:It is Solid, Small masses swimming in the space, but when it
falls on the Earth it called (Meteorites).
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2- Hydrosphere Cover:Hydrosphere is consist of Oceans, Seas, Lakes, Rivers and Ground Water.
The Water of Oceans, Seas Contains (Constant Weight) 35 gram per letter of different Salts, commonly of Sodium
Chloride type (NaCl).
Rivers Water:-contains generally less than 1 gram per letter Salts commonly of calcium bicarbonate and calcium
carbonate Water type.
Ground water:-quality of ground water depends on the ground water source, host Rocks and the migration of the ground
water. Ground water contains a wide variety of salts. Ground water may be Fresh water ( less than 1 gram per letter)
or Saline water (More than 10 gram per letter).
3-Biosphere Cover:Biosphere:-It is not true Cover. It is consist of Animals and Botany Creatures which deals with Hydrosphere, Atmosphere
and the upper part of Lithosphere cover. Biosphere plays important rule in the difference changes on Earth Crust.
4- Lithosphere Cover:The thickness of Lithosphere (Earth Crust) is from 5 km in the Oceans to 60 km in the Mountain regions.
The Wells drilling operations in the Earth Crust still about 10 km depth.
Earth Crust consist of Sedimentary, Igneous and metamorphic Rocks, covered by Soil in many regions of Earth.
The Soil is a Result of Disintegrate ,Erode of all kinds of Rocks with different thickness depend upon many factors.
The Rocky layers of Earth Crust are found below Soil and it is divided into tow Layers depend on Minerals consist it:-
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Earth Crust – sial and Sima Layer
Sial Layer:-It is the upper part of Earth crust .Its thickness between 2-15 km, Density about 2.8gm /cm3 .
Sail is consist of light colours Granitic Rocks ( Aluminium Silicate).
Sial Layer is thick at Land while it is thin or absent at Oceans.
Sima Layer:-It is the lower part of Earth Crust. Its thickness about 20-25 km, Density about 3.4gm /cm3 . Sima consist of Magnesium
Silicate. The upper part of this layer is Crystalline but the lower part is uncrystalline (classy texture).
Conrad Discontinuity:- Interference zone which is separated between Sial and Sima.
Sea Level
Conrad Discontinuity
Sial Layer
Sima Layer
Moho discontinuity
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11
Earth Bottom
The Seismology:-The Seismology is good method to know the consists of Earth Bottom.
Moho (Yugoslavian Scientist) is the first one who notice Difference in Earth Layers by using the Primary and Secondary Waves.
The Waves behaviour are changed at depth about 35km, this means changes in properties of rocks Called Moho Discontinuity.
Moho Discontinuity:-it is an imaginary limited zone separated between earth crust and mantle at depth between 35-50 km
(depends on its position in different Continents).
Earth Mantle
The information about the mantle is get by geophysical methods, since the increasing of seismologic waves speed is leading to collection of
Ferric-magnesium which is mean dark colour rocks. Mantle thickness is about 2650 km.
Scientists are identified two Layers:Upper Layer (Peridotite):-The Density is about 3.4 gm/cm3 consist of Basic or Ultra basic Igneous Rocks with more Dark Colure.
Lower Layer (Pallasite):-It is consist of basic Minerals and Ferric Metals.
Earth Core (Centro Sphere)
The Thickness of Core is about 3600 km. The Core consist of Ferric about 90%, Nickel about 10%.
Scientists collects information about the core of Earth by indirect methods by way of seismological waves and Meteor, meteorites analysis which
are fall on Land from time to time.
The analysis of Meteor and Meteorites shows Ferric, Nickel and some Chromium and Cobalt Metals
Some Specialists divided Core of earth into:1- Outer Core (fusion).
2- Inner Core (Solid).
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Earth Crust Consists
Average of Elements consists
Earth Crust as Weight% are:-
O=46.60
Si=27.7
The Oxygen percentage about 50% .It is not free, but chemically Combined with Another Elements
to form element oxides. Since Si is at second order, the expectation SiO2 is the most existence
,Then AlO, FeO CaO and so on. Usually more of Metallic oxide is combined with silicon oxide to
form Silicate Materials like Potassium, Aluminium, Silicate(KAl2SiO8) and Magnesium,
Silicate(MgSiO3).These minerals are Naturally Crystalline with out human made and named
(Minerals). The Minerals are find in Nature as free or Minerals consist rocks. Minerals are creating
from Atoms in Geometric Arrangement which is differentiate every one of Minerals.
A=l8.10
Fe=5.00
Ca=3.60
Na=2.80
Uncrystalline or Glassy Materials without geometric arrangement are not minerals.
K=2.60
Usually minerals are combined together forming Rocks.
Mg=2.10
Some minerals are Native like Gold, Diamond, Silver, Sulphur, Cupper, Graphite and Platinum.
Others=1.5
100%
Conclusion:- The earth crust is consist of:1- Crystals.
2- Minerals.
3- Rocks.
1- Crystal:- Crystal is Sold body, homogenous in chemical compound, particular by Crystalline Planes.
The Minerals are creation Naturally in Earth Crust by way of (crystallization).
Amorphous:- it is no crystalline minerals, unstable chemical compound , unstable crystalline building, without chemical Formula.
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13
Outer Properties Of Crystals
The properties of Crystal are depend on:1-Crystal Faces:-The Crystals have regular outer planes named (Crystal Faces) A .
2- Crystal Angles:- a-The angle between two neighbor faces is named (Edge Angle) B .
b-The angle between three neighbor faces is named (Solid Angle) C .
c-The angle between two faces is (Interfacial Angle), It can measured by two perpendicular columns on
neighbor and 0pp0site faces C .
3-Crystal Form:- It means groups of Crystals are similar in shape, Area and its Crystal situation. The Crystal can be form of one
shape of faces named (Simple Form) or many shapes named (Compound Form).
A - Faces
C
A
B
Closed Crystal
Face
B - Edges Angle
C - Solid Angle
Interfacial Angle
Faces and angle of crystals
Open Crystal
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4-Crystal Symmetry:- It means many of Faces, Edges and Angles are arranged around An Axis.
The Axis must be pass by Center of Crystal. This arrangements is called Crystal Symmetry. The Core
of Symmetry is Repetition of this Faces, Edges and Angles many times according to constant Low.
1-Plane Of Symmetry
Elements Of Symmetry
3-Center Of Symmetry
4-Inversion Axis Of Symmetry
2-Axis Of Symmetry
1-Plane Of Symmetry:- Plane is divided the Crystal into equals half, each of half is mirror picture for other. This plane Is called
Plane of Symmetry.
A
A-2
C
A
A-4
C
A-3
A-1
B
B
B
C B
A-7
A
A-5
A
C
A-6
Planes of symmetry in Sodium chloride Crystal (NaCl)
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15
2-AxisOf Symmetry
Axis:- It is an imaginary line pass by crystal center, that is means, If the crystal is rotated around this line (360 degree), face, edge and any line
will repeated twice or more.
2-fold axis (Diad)
3-fold axis (Triad)
4-fold axis (Tetrad)
6-fold axis (Hexad)
3-Center Of Symmetry
It is an imaginary, Central point into Crystal. The distance between faces , edges, and angles in certain side is equal to the other in opposite side.
4-Inversion Axis Of symmetry
This element collects between rotation symmetry and Inversion through the center of crystal . If the crystal has double inversion at rotation axis, i
needs crystal rotation for(180ْ )firstly, then inversion every face, edge, or surface in crystal through symmetry center until the crystal takes it
situation in vacancy. This Axis is called (Two-fold inversion) or(2). So for (3) , (4) and (6).
Extraction
Elements of symmetry are:-
1- Plane of symmetry.
2- Axis of symmetry.
3- Center of symmetry.
4- Inversion axis of symmetry.
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Crystallographic Axes
Crystallographic Axes are imaginary, three lines into Crystal, intersects at Crystal Center in point named (Axial Cross).
c+
1,2,3-Axial Angles
a1
2
1= α Angle
2=β Angle
3 =γ Angle
ba+
Axial Cross
b+
3
c-
Crystal Systems:- The Crystals are divided into two classes:A- Depend on the Axis lengths of Crystal and the Axial Angles between (α, β, γ ).
B- Depend on the grad of Symmetry elements in the Crystal.
On the basis of (A and B) above, the Crystal systems divided into (seven-7) systems:-
1- Cubic System.
2-Tetragonal System.
3-Hexagonal System.
4-Trigonal System.
5-Orthorhombic System.
6-Monoclinic System.
7-Triclinic system.
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17
1-Cubic System
A-Crystallographic axis 1-Three-Equals axis and Perpendicular on each others
B-Elements of Symmetry
1-Axis of Symmetry=13(3Tetrad-4 Triad-6 Diad)
2-Planes of Symmetry=9
3-Center of Symmetry=availab
3 Tetrad
4 Triad
c
Construction unit
12-Face
Sodalite Crystal
Mineral Crystals are:1-Diamond-C
2-Halite- NaCl
3-Galena- PbS
4-Fluorite-CaF2
5-Garnet (Mg,Fe,Ca)3Si3O12(OH)
6-Sodalite-Na8(Al6Si6O24)Cl2
a= b =c
b
a-b-c
Crystallographic Axis
a
6 Diad
2-Tetragonal System
A-Crystallographic Axis:-Three axis (two are equals, perpendicular on each other, while the third is longer or shorter and perpendicular on the
two equals Axis.
B-Elements Symmetry:- 1-Axis of Symmetry= 5 Axis(1-Tetrad,4-Diad). 2-Planes of Symmetry= 5
3-Center of Symmetry=available.
cْ
A= b ≠ c
90ْ
a
90ْ
Construction Unit
b
o
c
Zircon Crystal
Mineral Crystals are:- 1-Zircon-ZrSiO4
2-Rutile-Tio2
3-Cassiterite- SnO4
Crystallographic Axis
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3-Hexagonal System
A-Crystallographic Axis:-Four Axis (Three are equal, The Angle between each two equal Axis is 120ْ . Fourth axis is Longer or
Shorter and perpendicular the plane of three equal Axis.
B-Elements of Symmetry:1-Axis of Symmetry= 7Axis(1-Hexad, 6-Diad).
2-Plane of Symmetry= 7
3-Center of Symmetry= available
bَ
Mineral Crystals are:1-Quartz- SiO2
2-Apatite-Ca5(PO4)3 (OH,F,Cl)
3-Nepheline-(Na3(Na,k)(Al4Si4)O16
4-Beryl
a
a
a=a=a≠b
b
a
4-Trigonal System
The Trigonal system is like Hexagonal
System except:a-Three equal axis and fourth axis is longer
or shorter.
a-One Axis of Symmetry ( 1- Triad ).
b-Non existence any horizontal planes
of Symmetry.
َ
7-Axis
Construction unit
4 axis
Mineral Crystals are:1-Calcite- CaCO3 2-Corundum-Al2O3
3-Hematite-Fe2O3 4- Dolomite- (CaMg)CO3
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5- Orthorhombic System
A-Crystallographic Axis:-
B-Elements of Symmetry:-
1- Three unequal Axis.
1- Axis of Symmetry = 3 (Diad).
2- The Axis are perpendicular
each other.
2- Planes of Symmetry = 3
3- Center of Symmetry=available.
Mineral Crystals are:1-Topaz-Al2(SiO4)(OH,F)2
4-Andalusite-Al2SiO5
3-Sulfur – S
6-Barite-BaSO4
2-Anhydrite-CaSO4
5-Olivine- (FeMg)SiO4
a≠b≠c
c
a
b
Crystallographic Axis
Construction Unit
Sulfur Crystal
S
Anhydrite Crystal
Caso4
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20
6-Monoclinic System
A-Crystallographic Axis:1-Three unequal axis. 2-Two axis intersects (a and c) at oblique or inclined angle ( β ).
3- Third axis (b) is perpendicular plane of (a and c axes).
C
a
A≠b≠c
B-Elements of Symmetry:
1-Axis of symmetry = 1 ( Diad
conformable with (b) Axis
2-Plane of symmetry = 1
pass by (a and c) Axis.
3-Center of symmetry =available
β
β
b
Crystallographic Axis
Mineral Crystals are:1-Orthoclase-KAlSi3O8
2-Gypsum-CaSO4 2H2O
3-Mica-(K,Al,Fe,Mg)Si4O10OH
4-Talc-Al4(Si8O20)(OH)4
5-Hornblende- (Ca,Mg,Fe,Al)
(OH)2 (Si,Al)4O11
90 َ
Construction Unit
Orthoclase Crystal
7-Triclinic System
c
A-Crystallographic Axis
Oblique
Angle
A ≠ b≠ c
b
a
B- Element of Symmetry:-
1-Three unequal axis.
1-Axis of symmetry =absent
2-Unperpendicular axis.
2-Plane of symmetry =absent
3-Center of symmetry = available
Minerals Crystals are:1-Albite - NaAlSi3O8
6-Anorthite-CaAl2Si2O8
Plagioclase:-(2-Oligoclase) (3-Andesene)
(4-Labrodorite) (5-Bitonite)
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The Minerals
Minerals:-It is natural substance, solid, homogenous with systematic atomic building with particular chemical compound.
Minerals creation:-There are different sources and manner of minerals creation.
The minerals study is important to understand minerals accumulation, economic metals and ores deposits.
Minerals creation is divided into three sources:-
1- minerals creation of magma:1- Magma:-It is Fusion Rocks, Viscose, Dense, High Temperature for degree It is allow to Movement of Elements consist it.
Magma is available sub earth crust. But when Magma is moving up at Earth Surface through cracks, Fishers or
Volcanic activities, its fusion of Rocky is called - Lava
Most Minerals consist Earth crust are result of Magma or Lava Hardening.
The eight(8) Elements ( O, Si, Al, Fe, Mg, Ca, Na, k ) are compose about 99% of Magma. While Volatiles Materials
(Wat Vap, CO2, Cl, F, S etc) are compose 1% .
1-Magma Hardening is start with:- A- Silicates Minerals.
B- Oxides Minerals.
C-Sulfides Minerals.
A- Silicate Minerals:- 1- Plagioclase (Na, Ca)AlS3iO8
2-Olivine (Fe, Mg)SiO4
3- Pyroxene (Ca, Al, Fe, Mg)Si2O6
4-Amphibole(Ca ,Al, Fe, Mg)Si8O22
5-Mica K,Al,Fe,Mg)(Si4O10)(OH)
6-Orthoclase KAlSi3O8
7-Quartz SiO2
B- Oxide Minerals:-
1-Magnetite
Fe3O4
C- Sulfide Minerals:-
1-Galena PbS
2-Chromite FeCr2O4
2-Pyrite FeS2
3-Hematite Fe2O3
4-Quartz SiO2
3-Chalcppyrite CuFeS2
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22
2-Minerals creation of solutions:- Solutions divided into:-
A-Surface solutions.
B-Underground Solutions.
A- Surface Solution:-Oceans, Seas, (Saline Water) Lakes, and Rivers.
1- Evaporation of Solutions (High T) = Crystalline Minerals. (Depend on Solubility Product of Ions which is consist Minerals).
2- Exchange Reaction Between Solutions:- Sometimes Two solutions to be opposite , So reaction
together, resulting specialist Minerals:CaSO4+BaCO3
CaCO3(Calcite) + BaSO4 (Barite)
Crystalline Minerals
(Evaporative Salts)
3-Creatures Affected On Solutions:-Some Animals and Plants in Seas Extracts certain dissolved
Ions to Build their Skeleton, Bone, Shell :a-Coral-Extracts CaCO3-Building Oyster, Sponges, Shells.
b- Foraminifera - Extracts Si –Shell Building.
c- Bacteria – Absorbed Fe and S oxides.
All these Creations after Dead may be consist a create quantities of detriatal sediments in Sea Floor.
Solubility Product
CaCO3
MgCO3
K2CO3
Na2CO3
CaSO4
MgSO4
k2SO4
Na2SO4
CaCl2
B-Under ground Solutions
MgCl2
The underground Solutions divided into:KCl
1-Hydrothermal Solutions:- This Solutions are remaining of Magma Crystallization, very hot, high pressure and saturated with dissolved
NaCl
Oxides, Sulfides, Carbonate and so on. It is moving up faraway from its source through deep zones of Earth crust. During that It loss the
temperature and pressure gradually resulting hydrothermal Deposits which are divided into three type depend on Temperature and Pressure.
a-Hypothermal Deposits:- 500 - 300 C High pressure(deep zone) example
-Wolframite (Fe,Mn)WO4
-Molybdenite MoS2
-Cassiterite SnO2
b-Mesothermal Deposits :- 300 – 200 C Medium Pressure (Medium zone) example
-Calcite CaCO3 -Barite BaSO4
-Galena PbS -Sphalerite ZnS
C-Epithermal Deposits:- 50 – 0 C Low Pressure (shallow zone) example
-Quartz SiO2 -Calcite CaCO3 -Stibnite SbS2 -Opal Sio2 -Cinnabar HgS
Flourite CaF2
Marcasite fes2
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2-Evaporation of Assistant Dissolved Gas
Underground Solutions contains dissolved CO2 Gas as a result of Rainfall.
This is result H2CO3 (weak Carbonic Acid), Which is dissolved Limestone and to form Calcium Bicarbonate Ca (HCO3)2.The later is
Chemically unstable. So It is escape CO2 Gas and come back to Calcium Carbonate.
CaCO3+H2O+CO2
Ca(HCO3)2
Ca(HCO3)2 (Deposited Calcium Bicarbonate)
CO2+H2O+CaCO3 (Deposited Calcite)
(1)
(2)
This phenomena is clear in Rainy, Cavities and Limestone Regions, Since Limestone is Deposit in Conical Shape as above
Equation, Named:- Stalactite and Stalagmite.
Mountain
Travertine
CaCO3
Hot Spring
Water Table
Stalactite
Stalagmite
Cave
Aquifer
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Hot Body
3-Minerals Creation of Gases
After Minerals Crystallization of Magma and Minerals Deposition of Hydrothermal Solutions, The remaining Solution ( 1% 0f Magma)
becomes enrichment with Volatiles and Gases ( Water Vapor, Cl, CO2, F, S, B ) The later try to escape from Magma under suitable conditions
like Pressure decreasing through Joints, Faults and rock pores. The Volatiles and Gases may be Reacted together or with surrounding different
Rocks to form a new Minerals
NEW MINERALS:Volatile Compound) SnF2 + 2H2O
(Cassiterite) SnO2 + 4HF
Some times, Limestone affected by Hydrofluoric Acid (HF)
4HF + 2CaCO3
(Fluorite)2CaF2 + 2H2O + 2CO2
Another Minerals:- Tourmaline (Sl,B,Al,Fe,Mg,Na,O) Solution Rich Boron
Topaz Al2(SiO4)C(F, OH)2
Solution Rich Floured
When the Gases are near Earth Surface, they are try to escape through Volcanic Activities to form Sulfur S, Halite NaCl etc
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25
Minerals Creation Of Gas
A-Volatiles
Cassiterite (SnO2)
B-Another Minerals
Tourmaline – Topaz
C-Through Volcanic
S - NaCl
Minerals Creation Of Solutions
A-Surface Solutions (Oceans, Seas, Lakes):1-Crystalline Minerals (Evaporation)
Calcite(CaCO3)
Gypsum(CaSO4)2H2O
2-Exchage Reaction (Special Minerals)
Barite(BaSO4)
Minerals Creation Of Magma
A-Magma Hardening:1-Sillicate Minerals
Plagioclase(Na-Ca)AlSi3O8
Olivine(Fe- Mg)SiO4
Quartz(SiO2 – Mica
2-Oxide Minerals
3-Creature Affected
1-Coral (Extract – CaCO3)
2-Foraminefra (Extract – Si)
3-Bacteria (Absorbed –Fe – S)
B-Underground Solution:1-Hydrothermal Solutions
a-Hypothermal Solutions (Walframi Fe,Mn)WO4 Cassiterite (SnO4)
Magnetite(Fe3O4)
Chromite(FeCr2)O4
3-Sulfide Minerals
Galena (PbS) – Pyrite(FeS2)
B.-Lava Hardening.
Obsidian (Complex Rocks)
b-Mesothermal Solutions
Galena- PbS – Sphalarite – ZnS
c-Epithermal Solutions
Quartz- SiO2 – Cinnabar- FeS2
2-Evaporation Of Assistant Dissolved Gas
Stalactite – Stalagmite CaCO3
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26
A-Physical Properties of Minerals
It Means the Natural Properties of Minerals which is divided into:1-0ptical Properties:- Include Properties depend on Light such as Color, Play of Colors, Luminescence, Streak, Transparency, Luster, Tarnish.
2-Cohesive Properties:- Depend on Cohesion and Strength of Minerals such as Hardness, Cleavage, Parting and Fracture.
3-Electrical and Magnetic Properties:- Like Pyroelectricity, Piezoelectricity, Paramagnetic, Diamagnetic.
4-Specefic Gravity.
5-Thermal Properties:- Like Fusion Degree.
6-Sense properties:- Depend on Senses like Taste, Perfume and Contact.
1- Optical Properties
A-Color:- It is the first physical properties which is noticed in the Field, so it can be divided into.
1-Constant Colors:- Gold and Sulfur (Metallic yellow),
Malachite (Green) Cinnabar (Red).
2-Variable Colors:- Pure Quartz (Transparent), Impure Quartz (Rose, Smoky).
B-Play of Colors:- Some Minerals have different Colors through rotated it, because of light scattering, So Diamond is Good example. Another
Mineral show Silky Waves with rotation like Satin spar (one type of Gypsum).
C-Luminescence:- Some Minerals gives Light Radiation when it subject to Heat, X rays, Ultraviolent Rays, Fraction and Electrical Energy. The
light Radiation Color is different of the Mineral Color. When Radiation disappears with affected stopping the phenomena is
called (Fluorescence) Which is derive from Fluorite Minerals (CaF2). If Radiation Color stays during affected stopping,
Phenomena is called (Phosphorescence).
D-Streak:- It is Mineral Powder resulting from fraction on Streak Plane. Many Minerals have Streak Color different of Original Color, Such as
Pyrite(FeS2) is Yellow, while its Streak is Black. Chromite Mineral is Black Color, While the Streak is Brown color.
E-Transparency:- It is depend on mineral ability to pass light such as:-. 1-Galena, Gold, Pyrite are Opaque Minerals.
2-Pure Quartz, calcite, Gypsum layers are Semi Transparence. 3-Pure Muscovite is Transparence.
F-Luster:-This optical property depends on amount and kind of reflected light on Minerals. 1-Metalic luster--Gold , Silver , Galena , Pyrite.
2-Nonmetalic Luster:- 1-Glassy Luster – Likes normal Glass. 2-Adamantine – likes Diamond luster.
3-Pearly Luster, like Pearl luster – Talc and Mica minerals. 4-Silky Luster, One of Gypsum Kinds. 5-Earthy Luster, Likes Clay minerals Kaolin.
G-Tarnish:-Some minerals have different COLORS on mineral surface, as a result of outer layer analysis such as, Cupper, Bornite minerals.
Notice:- In tarnish case the original color is found only at new broken of mineral surface
.
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2-Cohesive
The Cohesive Properties are Depend On Cohesion and Mineral Elasticity, Which is result of Ionic arrangement Strength. It is divided into:A -Hardness:- It is a degree of Mineral Resistance for Scratch, Scrape, fragment and Corrosion.
Mohُs Scale of Hardness
1-Talc
Al4(Si8O20)(OH)4
2-Gypsum
CaSO4 2(H2O)
3-Calcite
CaCO3
4-Flourite
5-Apatite
6-Orthoclase
7-Quartz
8-Topaz
9-Corundum
10-Diamond
CaF2
Ca5(Po3)4(OH,F,Cl)
KAlSi3O8
SiO2
Al2(SiO4)C(F,OH)2
Al2O3
C
Human skin
Finger nail
Kitchen knife
Window Glass
Steel File
(Yakut in Arabic)
B-Cleavage:-Many Minerals are easy cleave in systematic directions named (cleavage Planes) the Later is always parallel to
Mineral Crystal face at weak point.
C-Parting:-Likes Cleavage but it is in depend on Mineral Crystal Face or Weak point, So it is a result of outer Natural factors after Minerals
Consisting like Pressure and Tension.
D-Fracture:- It is a Mineral Surface Shape which is result of mineral broken at non cleavage Plane. So there are many types of Fracture
Planes like Conchoidal, Flat,Unflat, Toothed, Earthy.
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3-Electrical and Magnetic Properties
A- Electrical properties:-1- Some minerals are good electric conductor like Graphite (C), some of oxides minerals (Hematite - Fe2O3) and
Sulfide Minerals (Galena – PbS).
2-Most Minerals are bad or Non Electric Conductor.
3-Some Minerals becomes charged with Electricity in case of Heating. This phenomena called (Pyroelectricity). Tourmaline Mineral is good
example which is use in temperature Measurement result from Bombs Explosion.
4-Quartz Mineral is charged with Electricity under direct Pressure (Piezoelectricity). It is useful phenomena for Industry of Radio and
wireless Instruments.
B-Magnetic Properties
Some Minerals have ability to pull a magnet while another's are Repulsive a Magnet.
A- Paramagnetic Minerals:- It is the Minerals which are Pull or Attractive Magnet like Magnetite (Fe3O4) – Hematite (Fe2O3)
B-Diamagnetic Minerals:- It is the Minerals which are Repulsive a Magnet like Quartz (SiO2) – Calcite(CaCO3) – Zircon(ZrSiO4) .
These Properties are used in Geophysical Explorations for some Metallic Ore Deposits like Fe, Ni Ores.
4-Specific Gravity:Mineral Weight in Air
Specific Gravity =
X Solution Density
Mineral Weight in Air – Mineral Weight in Solution
Specific Gravity is constant for the minerals at constant temperature and chemical condition .
.
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29
5- Thermal Properties:- Fusion is The Important Property to identified Minerals Which have different Fusion Temperature as:(Stepenite - 525C)
(Halite – 800C)
(Silver – 960C)
(Gold – 1062C)
(Quartz – 1650 1700C)
(Platinum – 1755C).
Some Minerals change directly to Gas with out pass in Fusion state like Arsenic
6-Sense Properties:- This Property is depend on Many Senses like Feel or Tough, Taste and Perfume as:1-Talc Mineral
Al4(Si8O20)(OH)4
2-Halite Mineral
3-Pyrite Mineral
NaCl
FeS2
Fatty or Soapy Tough.
Salty Taste.
With Heating – Sulfur perfume.
B-Chemical properties of Minerals
The Minerals are Consist of (Major Elements – High Percentage) and (Trace Elements – Very Low Percentage). The Detection of Minerals
Composition are by Methods of:A-Qualitative Method:- It is Quick method to detects major elements by Flame Color which is reflect Element Type.
B- Quantitative Method:-It Means Detection the Percentage of Elements which are Consist Minerals by many Physical and Chemical
methods:-
1-Chemical Methods:a-Volumetric Method.
b-Gravimetric Method.
2-Phsical Methods:a-Spectrographic Method.
b-X – Ray Fluorescence.
c-Electron Microprobe.
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30
B-Chemical properties of Minerals
The Minerals are Consist of (Major Elements – High Percentage) and (Trace Elements – Very Low Percentage). The Detection of Minerals
Composition are by Methods of:A-Qualitative Method:- It is Quick method to detects major elements by Flame Color which is reflect Element Type.
B- Quantitative Method:-It Means detection the percentage of elements which are consist minerals by many physical and chemical methods:1-Chemical Methods:- a
-Volumetric Method. b-Gravimetric Method.
2-Phsical Methods:- a-Spectrographic Method. b-X – Ray Fluorescence.
c-Electron Microprobe.
Crystal Chemistry of Minerals
It is depend on relationship between chemical composition and atomic building for mineral. The crystal chemistry science is divided into:1-Co – Ordination Number.
2-Chemical Bonds.
3-Polymorphism.
4-Isomorphism.
5-Pseudomorphism.
The First and Second Properties (1 – 2) are study at Inorganic Physical Chemistry while others ( 3 – 4 - 5 ) are Explain now:3-Polymorphism:- It Means More of one Crystal Shape are Crystallized from Same Substance, such as Diamond and Graphite are
Consist of Carbone ( C ) but Diamond is Crystallized in Cubic System, While Graphite is Crystallized in Hexagonal System, So there are
difference in all Physical Properties like Colors , Hardness and Specific Gravity. Calcite and Aragonite are Consist of CaCO3 (Calcite (Trigonal)
(Aragonite – Orthorhombic). Quartz and Tredemite are consist of SiO2 (Quartz – Trigonal), (Tredemite – Orthorhombic).
Note:-Two Minerals are Similar named Dimorphism, Three Are Trimorphism etc.
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31
4-Isomorphism:-It means two minerals are different in chemical composition and similar in crystal shape. It is series of minerals which is create
through replacement between two atoms almost are equals radius like sodium (Na) and calcium (Ca) to consist a Plagioclase Series. It
Crystallized in Triclinic system.
Plagioclase Series
Albite %
Anorthite %
1-Albite
2-Oligoclase
3-Andesine
4-Labrodorite
5-Betonite
6-Anorthite
100 - 90
90 – 70
70 – 50
50 – 30
30 – 10
10 - 0
0 -10
10 – 30
30 – 50
50 -70
70 – 90
90 - 100
NaAlSi3O8
CaAl2SI2O8
Plagioclase Series is different in chemical composition, So it has graduation of physical properties at two end sides.
5-Pseudomorphism:- It means mineral has constant atomic building and chemical composition while its outer shape like another mineral
such as Pyrite(FeS2) may be change to the Gothite Mineral(FeO2) but the later is still has the same outer shape of Pyrite.
Classification of Minerals:-There are many kinds of Classification:A-Economic Classification :- It depend on Economic Value of Mineral like Diamond, Gold, Platinum and Silver, Cupper and Lead, Zinc.
B-Crystal Chemistry:-like Chemical Bonds, Co-Ordination Number and Isomorphism.
C-Similar Basic Ions:-Depend on Basic Ions Consist Minerals such as:1-Minerals Group contains Iron (Fe):- (Hematite-Fe2O3) (Magnetite Fe3O4)
(Pyrite-FeS2)
(Limonite-FeO(OH)nH2O.
2-Minerals Group contains Cupper (Cu):- (Chalcopyrite-CuFeS2) (Borenite- Cu5FeS4) (Anargite-Cu3AsS4) (Chalcosite Cu2S).
3-Minerals Group contain Lead (Pb):- (Galena-PbS)
4- The best Classification for Minerals is depend on (Kind of Acidic Ions) of J.D.Dana an American Scientist, So Minerals are Classify
into Oxides, Sulphates, carbonates, Phosphates etc.
Note:-More than 2000 Minerals are Known yet.
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32
J.D.Dana Classification of Minerals
1-Native Elements (Minerals) Group:b-Semi Metallic Minerals:- Bismuth Bi
a-Metallic Minerals:- Gold Au
Arsenic As
2-Sulfide Minerals Group:- Galena PbS Pyrite FeS2
Mobidnite MoS2 .
Platinum Pt
c-Nonmetallic Minerals:- Diamond C
Chalcopyrite CuFeS Sphalerite ZnS
3-Oxides and Hydroxides Minerals Group:- a-Oxides (Anhydrous):- Corundum Al2O3
b-Oxides (Hydrous):- Limonite FeO.OH.nH2O
Opal SiO2.nH2O .
b-Hydroxides:4- Halides Minerals Group:- Halite NaCl
Cupper Cu Silver Ag.
Fluorite CaF2
Graphite C
Marcasite FeS2
Hematite Fe2O3
Gibbsite Al(OH)2
Sulfur S .
Arsenopyrite FeAsS
MagnetiteFe3O4
Brosite Mg(OH)2 .
Atacamite Cu2(OH)8.
5-Carbonate Minerals Group:- Calcite CaCO3 Dolomite CaMg(CO3) Aragonite CaCO3 Magnesite MgCO3 Weatherite BaCO3
6-Sulphate Minerals Group:- a- Anhydrous:- Anhydrite CaSO4
Barite BaSO4
Selestite SrSO4 .
b-Hydrous:- Gypsum CaSO42H2O Malanterite FeSO47H2O .
7-Phosphate Minerals Group:- Apatite Ca5(F,Cl,OH)(PO4)3 .
Monosite
(Ce,La,Th)PO4
Vanadenite Pb5Cl(AsVO4)3 .
8-Silicat Minerals Group:- It is the Biggest Group (consists about 90% of Earth Crust).
Olivine (Fe,Mg) SiO2
Hemomorphite Zn4(Si2O7)(OH)2.H2O
Wilstonite CaSiO3
Beryl Be3AlSi6O18
Tromolite Ca2Mg3Si8O22(OH)2
Muscovite KAl2(AlSi2O10)(OH)2 Clay Minerals (about – 120 Minerals)
Quartz SiO2 Orthoclase KAlSi3O8
Plagioclase (Na,Ca)Al2Si3O8
Anstatite Mg2Si2O6
Talc (Si4O10)(OH)2
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33
ROCKS
Rocks:- It is a Solid substance Consist of one Mineral or Mixture of Minerals.
Earth crust is Consist of:- 1-Igneous Rocks. 2-Sedimentary Rocks.
3-Metamorphic Rocks.
Rocks Cycle
Magma
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34
1-Igneous Rocks
It is create by Rocky Melting Harding with high temperature. (It named Primary Rocks because of all the Rocks are derive from it).
-Magma:- When Harding is below earth surface.
B-Chemical and Mineral Composition of Igneous Rocks
Oxides
Percentage%
1-Sio2
40-75
2-Al2O3
10-20
3-FeO
1-10
4-Fe2O3
1-10
5-MgO
1-10
6-CaO
1-10
7-K2O
1-6
8-Na2O
1-6
-Lava:- When Harding is over earth surface.
A-Properties of Igneous Rocks:-
1-In general it is crystalline rocks.
2-It is not contain Fossils.
3-No indication of strata shape.
4
2
3
1
16
CaO
Oxides
1- The right part of a side figure( 1 )is show
Rocks Rich in Si,Al,Na,K which means
Rocks contains (Orthoclase KAlSi3O8),
(Plagioclase rich in sodium NaAlSi3O8) with
little of Ca Plagioclase named (Acidic Rocks)
which are light color and low density.
The excess of SiO2 is forming Quartz
(with very little of ferromagnesium minerals).
2-The Rocks at Wright figure( 2 ) are rich In
Ca,Mg, and Fe but they are poor in K,Na and
relatively in Si, So this means rocks contains
(Plagioclase rich in calcium CaAl2Si2O8),
(ferro magnesium minerals, olivine (Fe, Mg)2SiO4
, Pyroxene group like
Augite(Ca(Mg,Fe,Al)AlSi2O6) No Quartz. This
rocks named (Basic Rocks)
which are blackish color and high density.
3- zone between 1and 2 are (Inter mediate Rocks)
which are represent mixed of 1 and 2 Rocks.
4-Ultrabasic Rocks.
12
8
4
50
55
60
SiO2
65
70
C-Melt Crystallization:-There are relationship between SiO2% and other oxides:Increasing of Na2O and K2O
increasing SiO2
Decreasing of CaO, MgO and FeO
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35
Effect of physical factors on Magma Crystallization
The Scientist N.L Bowen was explained The Crystallization of Minerals from Magma according to a certain sequence as:-
M
a
g
m
a
Olivine (Fw,Mg)Sio2
Pyroxene (Augite) (Ca(Mg,Fe,Al)AlSi2O6)
Hornblende (Ca,Mg,Fe,Al)(OH)2 ((Si,Al)4 O11)
Biotite (Mg,Fe)(OH)2(AlSi3O10
Plagioclase Rich in Na
First Crystalline Minerals
Temperature Decreasing
Plagioclase Rich in Ca
Orthoclase (KAlSi3O8)
Muscovite K2Al4(Si6Al2O2)(OH,F)4
Quartz SiO2
Olivine in non continue series is unstable, that when the condition of olivine is change like temperature decreasing, pyroxene is start
crystalline as a result of reaction between olivine and magma and Hornblende to biotite.
Anorthite in continue series is start to change by replacement of Na in place of Ca (with replacement of Si in place of Al ) to form
Plagioclase rich in Na instead of Plagioclase rich in Ca which results two kinds of rocks from (parent Magma) by way of
(Differentiation):A-acidic Rocks.
B- Basic Rocks.
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36
D-Classification of Igneous Rocks
Ultra basic
Rocks
Basic Rocks
Blackish Color-Light Density
Basalt
Gabbro
Intermediate Rocks
Andesite
Diorite
Acidic Rocks
Light Color-Low Density
Dacite
Granodiorite
Obsidian
Glassy Texture
Rhyolite
Fine Grains
Texture
Granite
Coarse Grains
Texture
100%
Orthoclase
(KAlSi3O8)
PlagIoclase
(Na,Ca)AlSi3O8)
Quartz
(SiO2)
50%
Olivine
Pyroxene
Ferromagnesium Minerals
Amphibole
Porphyritic texture:-Coarse and fine crystals in the same rocks.
Pumice:-Classy texture with fine spaces as a result of gas escape.
Biotite
Mica
0%
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Igneous Rocks Existence in Earth Crust
1-Plutonic Rocks:-It is Exist in Deep regions of Earth Crust, So it is reflect slow cooling and stable Pressure, Which is result big, equal and good
arrangement crystals (Coarse Grains Texture), Such as Granite, Diorite and Gabbro. This Rocks are Present in Earth
Crust as very large Masses called (Batholith). These Masses consist Parts of Rocky and Alep Mountains for Hundreds kilometers Long, Tens
kilometers Width and Unknown Depth.
2-Hypabyssal Rocks:- It is Exist in intermediate Deep Regions of Earth Crust, As a result of Magma Intrusive through Earth Layers. The Texture
of these Rocks is Fine to Moderate like Rhyolite, Dacite, Andesite and Basalt. Hypabyssal Rocks are present in Dikes shape (Mass of
Igneous Rocks are result of Magma up lifting through, vertical or oblique Fissures and Cracks).
Thickness of Dikes are many centimeters' to Tens meters . Or as Sill Shape (Parallel to Layers). So it is Exist as a Small
Dome named (Lacolith) with Diameter about Many Meters to Many kilometers, While Reverse Dome is Named (Lapolith) and Arciform
Saddle Shape Named (Phocolith).
3-Volcanic Rocks:- Igneous Rocks are Hardening on Earth Surface, As a result to flow of Lava through Volcanic Activity or through Cracks and
Joints. The Texture of Volcanic Rocks are Glassy or Microscopic Crystals because of Sudden Cooling of Magna.
Note:-a-Rocks contains Fine and Coarse Grains are Named Porphyritic Texture.
b-Pumice is Volcanic Rock with Fine Spaces as a result of Gas Escape.
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38
Shapes of Igneous Masses
Volcano
Sill
Phacolith
Dike
Lacolith
Lapolith
B a t h o l i t h
39 39
2-Sedimentary Rocks
Sedimentary Rocks:-It is Covers about 3 / 4 of Earth Crust. The last quarter is cover by igneous and metamorphic rocks. It is represented by:1- Sedimentary Rocks are represent by stratification (Many Layers) , Which reflect color, Thickness and minerals for each layer.
2-It is contain fossils (remaining of creatures).
3-Some Times it is Compose of particular Minerals like Halite (NaCl), Coal (C), Phosphates(PO4) and Petroleum.
A- Sedimentary Processes:- Four Processes are lead to creation of Sedimentary Rocks:1-Weathering. 2-Transportation. 3-Deposition. 4-Diagenesis.
1- Weathering:-
a- Wind.
b- Water (Fresh, Saline).
C-Glacial.
d-Creatures.
2- Transportation:-The products of Weathering are Transport far away to Deposition Regions. The Transportation take place by:a-River Water.
b- Wind.
c-Glacial.
The Transportation is stay continuous with stability of Transportation condition such as wind and river velocity.
3-Deposition:-The Transportated Materials are Deposit by either:a- Mechanical Deposition:- It is a result of changing for some mechanical agents like decrease of wind, current velocity, which result Clastics
or Mechanical Deposits such as gravel, sand silt and clay.
b-Chemical Deposition:- Some of transported materials are deposit in liquid or colloidal state by many chemical methods. So the Deposition
may be result of reaction between different transported solutions such as:1- Transported Solutions.
2-Transported Solutions with Gas.
3-Gas Escape of Solutions.
Na2CO3 + CaCl2
2Fe+2 + 1 /2O2 + 2H2O
Ca(HCO3)2
CaCO3 + 2NaCl
Fe2O3 + 4H+
CaCO3 + H2O + CO2
All these Deposits are called Chemical Deposits or Non Clastics Deposits. Like limestone, dolomite, gypsum and halite.
c-Organic Deposition:- Some creatures are build their bodies of dissolved or colloidal which presents in water, So after death , These
creatures are buried as Organic Deposits such as:1-Calcite (Oysters and corals are build their bodies of CaCO3). (Organic Calcite Rock). 2-Chert (Quartz is fine crystals).
3-Coal ( Remaining of vegetable with heat and pressure). 4-Iron and Sulfur (Bacteria is play as assistant agent in deposition of some ores).
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40
4-Diagenesis:-It
is all processes whichdeposits
affects inare
sediments
through
and afterof,
deposition
but before
hardening
under normal conditions,
2-Continental Deposits:-Continental
include all
the sediments
wind, rivers,
lakes and
glaciers:-41
Which
to change
in Texture
and Minerals
Consists
a- Wind Deposits:-1Sandleads
Dunes:It is a result
of weakness
in wind
power.as:-
2- cohesive
Talus Deposits:is accumulation
fragments
at calcite
edges of
highland
and mountains. sand stone.
a- Cementation:- By
materialsIt like
sand grains:-of rock
sand
(SiO2) +
(Caco
3 ) or FeO
Pressure
b- River Deposits:-1- Riverbed deposits:- Gravel, sand and clay as a result of reducing
at river velocity.
b-Compaction:- Here sediments are subject to Pressure like:Clay Sediments
Shale Stone
2- Flood Plains Deposits:- Like flood plain of Djilas and Forat river and delta (Delta of neel river). They are consist of
c-Recrystallization:- Growth
fineand
grains
to coarse grains without changing in chemical components like:gravel,ofsand
Clay.
Growth
c- Lakes Deposits:-1-Fresh Lime
lakes Sediments
deposits:- Like river de41posits.
coarse limestone
2- Saline Lakes Deposits:- As a result of evaporation of lake
water , different salts of chemical deposits are forming.
Replacement
d-Replacement:- It means replacement of Ion instead of other like:- Mg
CaCO3
(Ca,Mg)CO3 Dolostone.
d-Glaciers deposit:- Different large and small materials (Loading Deposits) are present in frozen river (Glaciers) with very slow motion.
e-Dissolving:- Rainfall (H2O) + CO2
H2CO3
H2CO3 + CaCO3
Ca(HCO3)2
When glaciers are dissolving, suddenly loading deposits are forming.
B-location of Deposition:-Deposition is either on continent, named Continental Deposits or in the marines, named Marine Deposits.
1- Marine Deposits: Most of marine sediments are carry by rivers (millions tens of sediments yearly) The size of these sediments are between
Boulders deposits (64 – 256 mm) to Silt deposits(1 / 16 – 1 / 256mm). The factor control deposition processes is (Sorting Power) which is
present in migration water. The Sorting Power plays important role in the sediment distribution so that the big sediments are first deposit,
Then the smallest and smallest.
Marine sediments divided into two kinds depend on site of these sediments:a- Littoral (Tidal zone):- This zone is controlled by action of sea waves and tide. The sediments is:- boulders, pebbles and coarse sand.
b- Neritic (Shallow-water zone) :- This zone is to extend off shore about 200 M depth. The sediments is:- Small gravel, sands and silt.
2-Continental Deposits:-Continental deposits are include all the sediments of, wind, rivers, lakes and glaciers:a- Wind Deposits:-1- Sand Dunes:- It is a result of weakness in wind power.
2- Talus Deposits:- It is accumulation of rock fragments at edges of highland and mountains.
b- River Deposits:-1- Riverbed deposits:- Gravel, sand and clay as a result of reducing at river velocity.
2- Flood Plains Deposits:- Like flood plain of Djilas and Forat river and delta (Delta of neel river). They are consist of
gravel, sand and Clay.
c- Lakes Deposits:-1-Fresh lakes deposits:- Like river deposits.
2- Saline Lakes Deposits:- As a result of evaporation of lake water , different salts of chemical deposits are forming.
d-Glaciers deposit:- Different large and small materials (Loading Deposits) are present in frozen river (Glaciers) with very slow motion.
41
When glaciers are dissolving, suddenly loading deposits are forming.
41
C-Texture of Sedimentary Rocks
Sediments and sedimentary rocks are consist of units named fragment grains or crystals. The description of these units called Texture.
Description is include:-1-Surface Feature of Grains:- Some grains are Shining and smooth, but another appears Score and pits.
2-Shape Of Grains:- It is Depend on roundness and sphericity. Some grains are angular, While anthers are
Clastics (Mechanical) Of
Sedimentary Rocks
1-Boulders > 256mm
2-Gravels
256 – 2mm
3-Sand
2 – 1 /16mm
4-Silt
1 /16 – 1 /
256
5-Clay
< 256mm
without angle, So between these two kinds all the grains are present.
For the Sphericity the Grains may be as Cylindrical Sphericity, Tablet Sphericity and Razor Shape.
3- Grains Size:- Many Scales are Known such as:-1- The sediment is called Sorted when all grains are equal.
2-The sediment is called Badly Sorted when grains are between large and small.
D-Primary Structure Of Sedimentary Rocks
The primary structure of sedimentary rocks are forming through Sedimentation Processes, As a result of natural conditions which are
control rocks forming. There is difference between primary structures and secondary structures, That the later are formed by different forces after
the deposition of sedimentary rocks like folds, joints and faults.
There are many kinds of primary structures such as:1-Stratification:-Sedimentary rocks consist of sequence layers, So every layer has :a- Thickness:- (Many centimeter is named Lamina – Many or hundreds meter is named Layer). Layer thickness is depend on volume,
nature of sediments and sedimentation environment. Some times sedimentary body is deposited as lens, tongue.
b- Bedding Planes:- (Two parallel planes are on and under the layer).
2-False or Cross Bedding:- One layer is consist of Many Lamina with different dip, As a result of changing in the strength of Current , Wind
direction, which is reflect the original environment at sedimentation time.
3-Ripple Marks:- It is clear at recent sediments of beach , as a result of wave Current and sand flats of desert.
4-Mud Cracks:-Mud is loss water by sun heat, Which is lead to shrink, and to crack of mud in hexagonal sides shapes. Sometimes cracks are fill
with sand or limestone deposit, So the later may be work cementing material. This criteria is useful to know ancient
42 42
environment.
E-Classification Of Sedimentary Rocks
Chemical And Organic Sedimentary Rocks
Chemical
Kinds Of
Sedimentary
Rocks
Texture
Chemical
Composition
Mechanical Or Clastic Sedimentary Rocks
Grains Size
Sediments
Rock Name
Rock Name
> 256 mm
Boulders
Conglomerate
Breccia
Clastic or
Non Clastic
CaCO3
(Ca,Mg)CO3
Limestone
Dolostone
2 – 256mm
Gravels
Conglomerate
Breccia
Non Clastic
CaSO4 2H2O
NaCl
Gypsum
Halite
2 – 1 /16 mm
Sand
Sandstone
CaCO3
SiO2 fine
Grains
Remaining of
Vegetable
Organic Lst
Chert
Coal
Organic or
Biological
1 /16 – 1 /256
< 1 /256mm
Silt
(50%Sand+50%Clay)
Clay
Siltstone
Clay stone
Coal Forming Stages :Plants Remaining in Swamps for a long Time
Bury
Anthracite
Beat
Heat and Pressure
Lignite
Bituminous
More Heat and Pressure For a Longer Time
Heat and Pressure for a Long Time
43
43
Metamorphic Rocks
Metamorphism:-
It is chemical, physical and mineralogical changes which is occur on original rocks. Igneous, Sedimentary and even metamorphic rocks).
When these rocks are subjected to heating or pressure or both., The metamorphic rocks becomes stable under new conditions. All the
metamorphism processes are happened in solid state with assistant of hydrothermal solutions which are present in Rock pores.
Classification of Metamorphic Rocks
Non Foliated Rocks
Original Rock
Foliated Metamorphic Rocks
Slate
Phyllite
Plutonic Igneous Rocks
Volcanic Igneous Rocks
Sedimentary Rocks
Marl
(Clay + 20 – 50% CaCO3)
Arkose
(Quartz+Minerals)
Graywacke (Qz+Minerals)
Orthoquartzite (Quartz only)
Limestone (CaCO3 + Min Oxide)
Coal (Bituminous)
*
*
Schist
Gneiss
*
*
*
*
*
*
*
*
*
Granular
Metamorphic Rocks
Quartzite
Marble
Graphic
Schist
(Anthracite)
Increasing at Temperature and Pressure
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Dynamic Geology
Geological observations shows very slow changes in the earth by comparative with human life, But we can notice this changes in different
geological methods. The energy is responsible for all changes in earth. there are two source for energy:-
A- Solar Energy (Outer Source):- It is the major source of energy on earth surface, Which is affected on atmosphere, hydrosphere and biosphere covers. The solar energy on
oceans, seas and lakes leads to water evaporation, Then rains, Ice fall, flowage to the rivers, Then the sediment will be transported and deposited. The rivers and wind ar
transport weathered rocks to the sedimentary basins and seas as transported sediments. Also solar energy is the reason of bioactivity through plant cover, sea creatures.
B-Earth Bottom (Inner Source):- Some scientists believes that, the source of heat which is drive convection current in mantle and core is both original heat from the planet
formation and heat from the decay of radioactive isotopes. The position of these hot sources forms a hot zones
leading to rise and down convection current, So the result is horizontal movements in the rock cover (Lithosphere), Which consist of many Plates float on the lower mantl
(Asthenosphere). When two plates are moving toward each other it named (Convergent Plate Boundary) ,and two plates are moving a part, (Divergent Plate Boundary) and
when two plates move horizontally parallel each other it named (Transform Plates Boundary).
The Energy is play continues changing in Earth Crust through two kinds of processes:1-Epigene Processes.
2-Hypogene Processes.
1-Epigene Processes (External Processes):It is a reaction result of all processes between atmosphere, hydrosphere and biosphere with earth crust. These processes leads to formation
of earth shape by different topographic (relief) phenomenon by:A-Weathering. B-Erosion. C-Transportation. D-Deposition.
A- Weathering:- It is all the processes leads to disintegrate rocks into small parts.
1- Mechanical Weathering:-It means Disintegrate of rocks with out changing in mineralogical composition.
a- Change in Temperature:- Daily or seasonally change in temperature leads to expansion and shrinking (Contraction) of rocks, Which is
leads to Rocks Exfoliation.
b-Unloading:- It means removing of layers weight from one layer, which is result sheeting of layers with some cracks, then easy to
disintegrate.
c-Bioactivity:- Roots of Plant between the rock cracks is lead to disintegrate of rocks.
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2-Chemical Weathering:-It is true reaction between hydrosphere and atmosphere with lithosphere by assistance of mechanical weathering (heat
secretion of creatures). The chemical weathering means analysis of rocks to another minerals may be different of original minerals as :
a-Oxidation:- Most minerals consist rocks are contain Iron like pyroxene, olivine, So oxidation of these minerals leads to Iron oxide on thei
surface (Red or Black color). This phenomenon is clear at desert region and called (Desert Varnish) like:
FeS2 + 2O2
S + FeSO4
(Ferris Sulfate is well Dissolved in water.
b-Carbonation:-It means reaction between CO2 (Atmosphere) with Rain Water to Consist H2CO3 as :CO2 + 2H2O
H2CO3 + H2O
Carbonic Acid reacts with Rocks contain Alkaline (Oxides of Sodium, Potassium and Calcium).
H2CO3 +CaCO3
Ca(HCO3) (Soluble in Water)
This reaction leads to disintegrate of Bicarbonate Rocks to form Caves with beautiful Formation of Stalactite and Stalagmite.
c- Hydration:-Union between Water and Some Minerals to form Hydrate Minerals.
KAlSi3O8 + 2H2O + CO2
Orthoclase
AlSi2O5 + 4SiO2 + KCO3
Kaolinite Sand
The Reaction result is show Resource of Kaolinite and Sand.
Another Reaction between Anhydrite and Water:CaSO4 + 2H2O
Anhydrite
CaSO4.2H2O
Gypsum
d-Dissolving and Organic Agents:- Some Minerals Dissolved in Surface or Ground Water, So water of Creature is increase Rocks
Humidity, Thus all these agents leads to Disintegrate of Rocks
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Weathering Products and Soil Formation
Mechanical and chemical weathering plays together to break and integrate all the rocks. The weathering products may be stay or
transported to other region as:1- Mechanical Weathering is Dominant at Polar and Desert Region.
2- At moderate regions, chemical weathering is dominant at summer while mechanical weathering is dominant at winter.
Example :- Granite is plutonic rock, It is Consist of ( Quartz + Orthoclase + Plagioclase + Little amount of Biotite and Muscovite + Trace
Chemical Weathering
amount of Zircon and Apatite).
a- Quartz, Biotite and Muscovite are Resistance Minerals.
b- Orthoclase is analysis by (Carbonation or Hydration) into
1- Colloidal Silicate + Potassium Salt
Dissolved in Water.
2- Remaining of Clay Minerals.
Chemical Weathering
c- Iron and Magnesium Minerals
1-Colloidal Silicate + Some of Iron and Magnesium
dissolved in Water.
2-Remaining of Clay Minerals.
Boulders and Soil are Weathering Products in very Large regions on Earth Surface.
B-Erosion:-It is mean rocks disintegrate (Weathering), transportation of weathering products and Deposition of these weathered materials.
Erosion is play either destructive or constructive agent……… How?
Agents of Erosion :- 1-Wind Action.
2-Surface Water Action
3-Seas Action..
4-Glacierse Action.
1-Wind Action : It is depend on wind velocity. when the velocity at high speed, It is carry maximum load of weathered materials to
different distance (Deflation) especially at dry Regions. here the wind action is Destructive, So by wind Abrasion.
a- Destructive Wind Action:-Differential erosion in the soft and hard of sequence layers are forming many geomorphologic
Phenomenon like:-
1- Mesa:-It is local platform surrounding by gentle slope figure1A . 2- Butte:- It is an isolated platform surrounding by step slope figure1B.
3- Mushroom:- It is an reverse half dome with neck figure I C .
4- Oasis:- It is a desert depression by wind action.
47
Figure 1 Some of Geomorphologic Phenomenon by Wind Action
C- Mushroom
B-Butte
A-Mesa
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48
B-Constructive wind action:Wind Action becomes constructive due to the losing of wind velocity. So the load of wind (different detrital Rocks)
descend on the land to form either:1-Unsteable Phenomenon like Ripple Mark Figure 2 A .
2-Steable Phenomenon like Sand Dunes and Loss Deposits Figure 2 B.
Figure 2 A
Wind direction at sand flats of desert
Ripple
M arks
Waves current direction at sea beach
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49
Faster Wind
Wind Direction
Slower Wind
10َ
30
َ
Sand Dune Forming
Figure 2 B
Sand Dunes Forming is a result of reducing at wind velocity. Sand dues are growth around small part (Gravel or Sand) called Nucleus.
Some times it moves to another place with wind direction by way of Sand Dunes Migration. Dunes highest is between (few – many Tens) feet.
Loess Deposits :It is very fine grains (Dust) of quartz, mica, calcite and feldspar with reddish yellow, suspended in air for a long
distance, Then it is descend on earth surface by gravity or rainfall. The typical formation is Loess Area in France.
There are many kinds of Sand Dunes Figure 3 :50
50
1- Barchan (Crescentic) Dunes
4-Star Dunes
Figure 3 Types of Sand Dunes
2—Transvers Dunes
3-Longitudinal Dunes
5-Seif Dunes
6-U-Shape Dunes
Iraqi Sand Dunes
West of Beji – Tikreet
East of Najaf
West of Samawa51
West of Nasiriyah 51
2-Surface Water Action
Surface Water action is include :-
a-Rains:- It is rains fall on earth surface in different quantities. It is depending on:1- How many meter, the land is above sea level?.
2- How much far away of sea?.
b- Torrent:- When the rains are fall on the high lands, torrent is shovel a lot of detriatal
materials to form deep waterway (Canyons) .
c-Water of Ice melt:- During spring season, The water of Ice melting is carry detriatal
materials similar to rain.
Is the Rains, Torrent and Water of Ice Melting are Destructive or Constructive?.
d-Rivers:- Rivers are transported the sediments by one of ways:1- Deposits in Form of Dissolved Materials:- like salts (CaHCO3, CaCO3, CaSO4, NaCl).
2- Light Weight Deposits in Form of Suspended Materials:- like clay minerals , Silt,
Very small Particles of Different Rocks.
3- Heavy Deposits in Form of Jump, Roll and Sliding Deposits:- like relatively large grains of different sources.
Rivers have three stages from it s originated (Recharge Area) to mouth at sea (Discharge Area) :1- Youth Stage.
2- Mature Stage.
3- Old Stage.
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Flood Plains
1-Youth Stage
Properties of Youth Stage:a- the cross section of River at
Youth Stage is V shape.
b- Ability to Grave its Riverbed.
c- Waterfalls are Present.
d- The Branches of River are Short
and Little.
e- It can not be Navigation of Ships
in this Stage.
f- It is Good for Electricity
Generation.
g- Dijla River is represent this stage
from (Armenia Highland) in
Turkey to Mosel City in North Iraq.
2-Mature Stage
Properties of Mature Stage :a- River is More Width and it had
Gentle Slope on both sides, So the
shape of Cross section is like half
Cycle.
b- The Branches is more than Youth
and Longer.
c- Velocity of Water is Moderate, So
it is suitable for Navigation.
d- Area between Mosel and
Baghdad is represent Mature Stage.
Stages Of River
3-Old Stage
Properties of Old Stage:a- River depth and Slope of both
Sides are Little.
b- Low Flow and much Deposits.
c- Flood plain is Present on both
sides of River. so the River was
loosed its Energy for Graving, Thus
the River is begin to Deposits to
form Flood Plain.
d- Meanders are Present in this
Stage.
e- Area between Baghdad and
Basra is represent this Stage.
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2-Hypogene Processes
(Interior Processes)
Hypogene processes means all internal processes which is lead to either a quick processes like earthquakes and volcanoes or slow processes
ike oroginic movement. plate tectonic theory explains this processes.
Plate Tectonic Theory
Plate Tectonic is the study of the origin and arrangements of the broad structural features of earths surface, including not only folds and faults,
but also mountains belt, continents and earthquakes belts.
The basic idea of Plate Tectonics is that, earth surface is divided into eight large Plates plus Few smaller Plates makeup the outer shell of
Earth (Lithosphere). Plates are move slowly With intense geologic activity occur at plate boundary where plate moves away from one another.
Volcano
Convection Currents
Mid- Oceanic Ridge
(Rift Valley at Ridge Crest)
Oceanic Trench
Outer Core
Asthenosphere
Inner Core
(Lower Mantle)
Figure 4 Convection Currents
Lithosphere
(Earth Crust + Upper Mantle)
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54
Scientists believes that the source of internal thermal Energy in Mantle and Core is either:A- Heat of Planets Formation.
B- Heat From the Decay of Radioactive Isotopes.
It is Forming very hot regions to Consist (Convection Current). Which is lead to horizontal Movement in Earth Crust (Figure 4 )
Floats on Asthenosphere (Lower Mantle).
Alfred Wegener A German Meteorologist At 1900 and Harry Hass An English Geologist At 1962 Suggests That:1- Our Continental can be collected together like Pieces of cutting Picture (Split begin about 130 million years ago).
2- Alfred Wegner noted that, south America, Africa, India Antarctica and Australia have almost identical the late Paleozoic rocks
and Fossils.
3- Wegner also reconstructed old climate zones by steadying Coral Reef (Warm Water) Cross Bedding( Desert Environment)
and Glacial Till (Cold Environment).
4- He found that, ancient Magnetism Poles were in different positions than the present Poles (Polar Wandering).
5-Harry Hass 1962 suggest that the Sea floor moves away from the Mid – Oceanic ridge as a result of Mantle Convection Currents.
6- He Suggests that, the Ridge Crest with Sea floor moving away from it on either side, ha been Called (Spreading Center).
7- The sliding of Sea floor beneath a Continent or Island Arc is named (Subduction).
8-The Sea floor moves at a rate of 1 – 24 centimeter per year.
Why Does the Sea Floor Move (Spreading)?
Sea floor spreading is a result of deep, hot of Mantle Convection Current, since a hot Rocks is rising (Low Density), and Cold Rocks
is descend (High density).
Hypogene Processes (Interior Processes) are Divided Into:A- Quick Processes:B- Slow Processes:-
1-Earthquake. 2- Volcanoes. 3- Geysers and Hot Springs.
1- Orogenic Movement.
2- Epeirogenic Processes.
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A-Quick processes
1- Earth Quakes:- It Is shaking of earth surface, as a result of sudden discharge of energy which is stored in Earths Rock.
strain
Fault Displacement
stress
A
B
Earthquake
C
Figure 4
Figure4 A- Is show rocks under the stress by tectonic forces in the earth.
B- Is show rocks have a bending or deformation shape (Strain).
C-Is show rocks are break with discharge of energy is released as Seismic Waves which causes the earthquake.
The break of earth Rocks is called Fault with move past one another along a fault. Usually, the energy stored in the rocks is more enough to
break the rocks suddenly and making earthquakes. The move of rock through a fault may be vertical or horizontal or both.
There are two idea for faulting:1-Classic (Old) idea:-It must be a very large stress acting to break rocks along a fault because the faults are very hard.
2-New idea:- Fault are weak, so little stress is enough to make rupture then earthquakes.
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Rocks behavior near earth surface is brittle, While at depth it subjected to more temperature
and pressure, which leads Rocks behave to be ductile rocks.
This means there are a limit of depth for faulting. Usually earthquakes are happened with faults displacement, But in some earthquakes are not with
urface faults displacement like earthquakes of eastern united states. Earthquakes also happened during volcanic activity.
Seismic Waves
Epicenter
Focus s
The source of seismic waves is Focus, While
the Epicenter is a point on earths surface vertically above
the Focus Figure 5.
There are two kinds of seismic waves:A- Body Waves:-It is seismic waves travels through
underground rocks in all ways, So it is divided
into two types:1- P-Waves (primary):-In this waves, Rocks are
shaking front and back parallel to direction of P
waves. The properties of this waves are:a-Travel near earths crust at velocity about
6 kilometers per second(figure-6- A).
b- P- Waves is faster than other waves.
c-It is first reaches the station of recording.
d-It can pass through solid, liquid and gas.
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2-S – Waves (Secondary):In this Waves, Rocks are shaking up-down through direction of waves.
The properties of S Waves (Figure 6 B) are :a-Velocity is about 3 kilometers per second (about half Velocity of P Waves).
b- S – Waves reaches station of recording after P- waves.
c- It can pass through solid only.
B-Surface Waves:Surface waves are more dangerous of P and S waves, because they toughs our life, building, railway, roads, power line, bridge. Generally
surface waves are slowest than P and S waves, So they can doing more damage by slow movement and (relatively) long time
Through surfaces of earth.
There are two kinds of surface waves:1-Love Waves:-The properties of love waves (Figure 7 A) are:a-Similar to S waves but no vertical replacement.
b-Direction of love waves are perpendicular to direction of love waves at two sides away.
c-Love waves cannot travel through liquids (like S waves).
d-It attack building, highways at their supports.
2- Rayleigh Waves:-The properties of rayleigh waves (Figure 7 B) are:a-The behavior of rayleigh waves are like ocean waves.
b-Rayleigh waves are causing movement in earth surface as cylindrical way in opposite
direction to waves way.
c-Rayleigh waves are break and destroy the building because they results earth surface
up – down movement for (relatively) long time.
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Waves Propagation
Particle Motion
A
A-Primary-W
Expand
Compress
(Figure-7-Surface Waves)
(Figure-6-Body Waves)
B-Secondary-W
Particle Motion
Rayleigh Waves Propagation
B
Waves Propagation
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A-Measuring of Earthquakes
Measuring earthquakes includes amount of size, depth and location of earthquake.
Seismometer is the instrument used fore measuring of an earthquakes exactly (figure 8 – 9). The principle of the seismometer is to make a mass
of heavy weight stable through the earth surface, moves as possible ,so the mass work like pointer (with pen) for determination
The amount of earth surface up-down motion. Always they put three seismometer in one container to detect the earth surface motion in X , Y
and Z directions.
Seismograph is a recorder instrument for earth surface vibration which is detected by seismometer.
Seismogram (Figure 10 )is the paper record of earth surface vibration and can be used to calculate the earthquakes strength. almost all the
countries have earthquake detection stations. after short time seismograph within stations starts to receive seismowaves , the P waves then S
waves, then the surface waves arrives to station of seismographs.
Finally the geologists calculated these seismowaves to get the site and magnitude of earthquakes.
B-Earthquakes Location
P and S are two body waves migrate through earth body in different velocity, So they divergent and the first P Waves reach Earth quake
station , Then S Waves after time interval. (here we can separated between the first time reach P Waves and S Waves). In Order to ge
Epicenter (surface point above Focus) Figure 10 and 11 , It must be find at least three seismogram record (Seismograph Stations). From time
interval (between two time travel curve), We can find the true distance on earth surface on special paper (seismogram paper), By drawing
three intersect cycles on a map, the point of an Intersection is Epicenter.
Also from analysis of seismogram, We can calculate the depth of earthquakes.
According to focus depth, earthquakes are divided into three groups:1-Shallow Focus
0 – 70
kilometer
85% of Earthquakes.
2-Medium Focus
70 – 350 kilometer
12% of Earthquakes.
3-Deep Focus
350 – 760 kilometer
3% of Earthquakes.
Why?
60 60
Constant, Pen Elevation
Moving Up
Normal
Figure 8 Seismograph – Vertical Movement
Moving Down
Hard Tower
Wire
Heavy Weight
Rotating Drum
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61
Figure 9 Seismograph Horizontal Movement
1-Distance between Epicenter and London :- 4 min x 60 x 6 km /sec =1440 km
2-Distance between Epicenter and Moscow :- 6 x 60 x 7 km /sec = 2520 km
Epicenter
3-Distance between Epicenter and Baghdad :- 11 x 60 x 6 km/sec = 3960 km
Moscow
London
London
Earthquake Time-Minute
25
Moscow
Baghdad
20
11 minute
interval
6 minute
interval
15
Surface
Waves
P
4 minute
interval
10
Baghdad
5
1000
2000
3000
Distance From Epicenter (Kilometers)
Figure 10 Seismogram
4000
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62
Figure 11 Location of
Earthquakes
2-Volcanoes
What is the Volcano?
When lava is being viscous and spread out of earth body as a flood, Lava is forming a hill or mountains named a Volcano Figure 12.
Table 1 is show characteristic of different type of Volcanoes.
Table 1 Types of Volcanoes
Type of Volcano
Form of Volcano
Size
1-Basalt Plateau
Flat to gentle Slope
2-Shield Volcano
3-Cinder Cone
4-Caldera
Type of Magma
Style of Activity
Examples
Large and thick
Basalt
Gentle eruption from long
fissure
Columbia River
plateau
Slope 2ْ – 6ْ
Up to 9000 m
high
Basalt
Gentle, some fire fountains
Hawaii
Moderate slope
100 - 400 m high
Basalt or Andesite
Ejections of pyroclastic
material
Paricutin Mexico
Cataclysmic explosion
leaving a circular
depression Called
Caldera
Less than 40 km
in diameter
Granite
Very Violent
Yellowstone, San
Juan Mountains
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63
Figure 12 Volcano Formation
Volcano
Volcano Mountain
Volcano Pipe
Volcano Hill (Extinct)
Lava Flow
Sill
Dike
Plutonic Body
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64
Why Rocks are being in melting state?
The upper mantle (depth 100 – 350 kilometer) is named Asthenosphere which is consist about 1 -2 % of mantle. asthenosphere is Molten layer.
Three factors controls the upper part of asthenosphere to form Magma.
1-Temperature increasing:- At natural low, Solid is being melt when it being hot . So increasing of temperature will be melt a hot rock. Volume
of melting magma will increase about 10% than original rock.
2-Pressure decreasing:-When minerals melts, atoms composed it becomes disordered and moves freely. The temperature in asthenosphere is
enough to melt rock, but the high pressure prevents the rock to expand , and cannot melt .When the pressure decreases, big quantity of
asthenosphere will melt.
3-Water steam under pressure:-Generally, wet rock melts at lower temperature than dry rock.
4-Minerals mixing ratio:-Experiments are explain that, melting temperature for quartz(SiO2 is about 1600C and orthoclase(KAlSi3O8) about
1300C. mixing 40% quartz and 60% orthoclase, The melting temperature is reduce to about 1000C.
When and how Magma is forming?
The composition of magma is control by geologic place. Basaltic Magma is associated with oceanic crust, While Granitic Magma is common
in continental crust.
Magma is forming in three Tectonic areas:1-Magma of spreading center:When lithospheric plates are separate at spreading zone, viscous, hot asthenosphere leaks up way to fill the gap result of convection currents
as at Figure 13.
As asthenosphere rises, pressure is releases to form melting Basaltic Magma , moreover the magma is of lower density than surrounding rock,
thus magma is up word to ocean surface as Lava flow. Ocean contains most Spreading center (Some spreading center. Like the African Rift
occur in Continents with Basaltic magma too), and they forms the Mid-Oceanic Ridge system.
The Magma created at the spreading center erupts from the ridge beneath the sea floor and solidifies to form new Oceanic Crust as Lava Flow
at a few places such as Islands, which is result of Ridge rises above Sea level, as Lava flow.
2-Magma of Mantle Plume:The Magma Plume is rise because it is hotter than the surrounding Mantle and less dense and more floating. Since the plume is rise, pressure
– release melting enough beneath the Lithosphere to form Magma , Which is rise up to earths surface Figure 14
The Magma Plume may be occur in Continent like the (Yellowstone hot spot at Yellow stone National park), that the hot spot is responsible
for the Volcanoes and hot springs. If the Mantle Plume rises bellow the Sea floor, Volcanoes Islands is build up like Hawaiian Island65
at
Pacific Ocean.
65
Spreading Center
Mid - Oceanic Ridge
Sea Level
Lithosphere
(Earth Crust + Upper Mantle)
Oceanic Crust
Magma
Convection Current
Rising Asthenosphere
Figure13– Magma of Spreading Center
3- Magma of Subduction Zone:- The subductinn plate of oceanic crust is saturated with water. Through the subduction, the water forming
stream into hot asthenosphere, As the subduction plate descends oceanic plate is slip asthenosphere rock down with it Figure 15. Rock from the
Deeper part in the Asthenosphere, then flow up word to replace the Sinking Rock, leaving zones of less Pressure at hot Rock rises.
Also Friction between Oceanic Crust and Continental crust is Generate heat in Subduction zone. Now water Vapor, less pressure and frictional
heating plays together to melt Asthenosphere Rock. Volcanoes and Plutonic Rocks are the Result of Subduction Zone The Pacific North west is
example of Volcano, So the Granitic Cliffs of Yosemite and Andes mountains are example of plutonic rocks
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Volcano
Extinct Volcanoes
Lithosphere
Oceanic Crust +Upper Mantle
Oceanic Crust
Magma Formation
(Partial Melting)
Rising Mantle Plume
Asthenosphere
Rising
Mantle
Plume
Figure 14 Magma of Mantle Plume
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3-Geysers and Hot Springs
Ground Water may heated by:A-Naturally earth Layers temperature is increase about 25-35 ْC per one kilometer depth in earth Crust, So if ground water is leakage down
about 4 kilometer, it will heated to 100 ْC. The hot water will rise up because of low density, While the cold water is moves down. This
type
of hot springs is rare.
B-At the regions of Volcanic activity, Magma is still near Earth Surface and it can heat Ground Water. Hot spring in This case is Familiar
(like hot springs and Geysers in Yellowstone National Park – United States) Figure 16 .
C- Some hot sprigs have disagreeable smell of H2S Gas dissolved in hot water, which results of reaction between hot water and sulfide
minerals (Exothermic Reaction) like (Galena – PbS Pyrite – FeS2 Sphalerite – ZnS And Chalcopyrite – CuFeS2).
Figure 16 Geyser Formation
Narrow Neck
Steam
Empty Chamber
Aquifer
Hot
Body
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