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Sedimentation & Stratigraphy
g p y
( G 202 )
Course Coordinators:
Dr. Ahmed Sadek
Dr. Ahmed El-Sabbagh
Geology department, Faculty of Science, Alexandria Univ.
Part I
( Sedimentation )
Introduction to
Sediments & Sedimentary Rocks
Dr Ahmed Sadek
Dr.
Course objectives
This course aims at:
• Providing
g an introduction to the basics of sedimentation
processes and sedimentary deposits.
• Generate in students an appreciation of the importance of the
sediments and sedimentary rocks.
• Assessing the textural and mineralogical properties of sediment
and sedimentary
y rocks.
• giving a survey of the description and classification of sediment
and sedimentary Rocks.
• Providing a brief review of the full range of sedimentary
environments.
Course Contents
Part I: Sedimentation
1. Introduction (definition of sediments and sedimentary
rocks
k and
d th
their
i iimportance)
t
)
2 Nature,
2.
Nature sources and formation of sediments &
sedimentary rocks, sedimentary rock cycle
3. Texture of sedimentary rocks (mechanical analysis grain fabric, roundness, sphericity and surface textures
of grains, porosity & permeability) and its importance
4. Chemical and mineralogical composition and its
significance
5. Simple genetic classification of sedimentary rocks
Schedule of Course Assessments
Methods of Assessment
Weighting of
Assessments
Time
Semester Work
Mid-Term writing exam
Final practical exam
Final-Term
Final
Term writing exam
Oral Exam
5%
10 %
15 %
60 %
10 %
Weeks 4 & 11
Week 8
Week 16
Week 17
Week 17
Total
100 %
List of References
- Blatt, H. Middleton, G.V. and Murray, R.C. (1980), Origin of sedimentary Rocks, 634 p.,
Prentice-Hall, New Jersey.
- Tucker, M.E. (1982), sedimentary Petrology An Introduction, 251 p., Blackwell
S i ifi Publications
Scientific
P bli i
- Levis, D.W. and Mc Conchie, D. (1994), Practical Sedimentology. Chapman & Hall,
N.Y.
- Sam
S B
Boggs (2006)
(2006): Principles
P i i l off Sedimentology
S di
t l
andd Stratigraphy,
St ti
h 4th Ed.
Ed Prentice
P ti Hall,
H ll
662 pp.
Introduction to
S di
Sediments
t & Sedimentary
S di
t
Rocks
R k
WHAT ?
Definition of sediments &
sedimentary rocks
WHY ? Importance of sediments and
sedimentary rocks
HOW ? Sedimentary rocks are formed?
WHAT ? Textures and Mineralogy of
sediments
di
& sedimentary
di
rocks
k
HOW ? Sedimentary rocks are classified?
Introduction & Definitions
What is Sedimentology ?
• It is the branch of the geological science
which deals with the study of:
m
,
1. sediments,
2. sedimentary deposits
3 sedimentation processes,
3.
processes and
4. sedimentary rocks.
Stratified
Sedimentary
rocks
Sediment
What are sediments?
Sediments are:
• loose, unconsolidated particles
• formed at or near the earth's surface under low T & P,
• formed in response to processes of chemical and
physical weathering, erosion, transportation and
deposition.
What are sediments?
Sediments may be:
• A fragment of rock, mineral or shell (clastic sediments)
Rock fragments
Quartz grains
Shell fragments
• Crystals which chemical
precipitated directly from water
(chemical sediments)
crystals
• Shells and skeleton of marine
organisms
g
((biochemical sediments))
Shells
 The clasts sediments include:
• Terrigenous clastic sediments: The solid grains derived from
weathering of previous rocks (sedimentary, igneous,
metamorphic) and transported, redistributed and deposited
by surface processes to form clastic sedimentary rocks
Rock fragments
Q
Quartz
t grains
i s
mud
d
• bioclastic sediments: those generated by the mechanical, chemical
and biological breakdown of skeletal parts.
Shells
Shell fragments
• volcaniclasts sediments: those generated by volcanic eruptions.
 Chemical and biochemical sediments:
Are derived from precipitation of authigenic minerals from
solutions by biological and inorganic chemical processes
to form rocks without the transportation
p
of the p
particles
and form chemical and biochemical sedimentary rocks.
Shells
Rock Salt
Flint
Growth in position by organic processes (e.g.,
carbonate reefs, coals)
reef
What is a sedimentary deposit?
•It is a body of solid materials (sediments)
accumulated at/or near surface of the earth
within a specific sedimentary environment.
Sand Dune deposits
p
Swamp deposits
Lake deposits
p
Beach deposits
What is Sedimentation?
Sedimentation is the process of sediment
accumulation
accu
u at o ((falling
a g do
down)) in tthe
e ea
earth
t su
surface
ace u
under
de
the influence of certain forces (e.g. gravity, winds,
streams currents,, glaciers,
g
, tubidityy currents,, ..)) and is
primarily applied to the settling of solid particles from a
fluid.
What are Sedimentary Rocks?
• Sedimentary rocks are secondary rocks (i.e. they are
formed from pre-existing rocks)
• They are formed via the deposition and lithification
(diagenesis) of loose sediments, which are the product
of
f chemical
h i l and
d physical
h i l weathering
th i of
f All rocks
k
(igneous, metamorphic and sedimentary).
• They form at or near the earth's
earth s surface at relatively
low temperatures and pressures primarily.
Stratified
Sedimentary
rocks
Sediment
Reefal limestone
Bedded
conglomerate
Beach rock
Limestone & Sandstone
Limestone & shale
Limestone
Abundance of Sedimentary Rocks
- Cover 75 % of the Earth's surface
- Make up about 5% of the total volume of the Earth'crust.
- Have an average thickness of about 1800 m on the continents
Marine Sediment
& Sedimentary Rocks
Continental Sediment
y Rocks
& Sedimentary
Why ?
Importance of sediments and sedimentary
y rocks:
Academic importance:
 deduce the environments and processes off
deposition, palaeogeography and palaeoclimatology
 understanding
d
di off the
h E
Earth's
h' geological
l i l hi
history.
 Stratigraphic correlation.
Economic importance:
• S
Source rock
k for
f petroleum
l
oilil and
d
gas.
• Reservoirs for the petroleum oil
oil,
gas, freshwater
• Cap
p rocks ((Seal)) for reservoirs
such as evaporites, mudrocks.
• Raw materials for the Mud Fluids
(
(e.g.
Bentonite
B t it (clay
( l minerals).
i
l )
•Source of ores of many metals such as: iron, manganese, lead
ores, and others.…
• Raw materials for the ceramic and Portland cement industries
industries.
• Some of them are used as fertilizers such as phosphates,
some nitrates.
• Some of them used as raw materials for building as sand and
gravel.
How a sedimentary rock is formed?
Sedimentary
y Cycle
y
• It is a part of the major rock cycle which shows the manner to form new rocks
(igneous, metamorphic and sedimentary rocks) from old ones through geologic time.
• Sedimentary cycle takes place at or near the surface of the earth under normal
conditions of temperature and pressures.
Sedimentary
Cycle
y
explains:
p
How a
Sedimentary
rock is formed?
Weathering - it is the decomposition and breakdown of rocks and
minerals at the earth's surface by mechanical and chemical processes.
Erosion - it is the removal and movement of weathered material from the
site of weathering by moving water, wind, glaciers, or gravity.
Transportation - The weathering products may still located in situ or
undergone variable long or short transportation. Transporting medium
are water (including river, streams, waves, ..), wind, glaciers and gravity.
Deposition – the accumulation of transported sediment in the basin of
deposition (ocean, lakes, lagoons, inland valleys) as layers of loose
sediment.
Lithification - it is the process of transforming a loose sediment into a hard
sedimentary rock.
- It involves different processes: cementation, compaction,
recrystallization,
t lli ti
Uplift - It the process of uplifting of the rocks by the effect of tectonic
movements.
movements
- It leads to the exposing of the rocks whose are subjected to the
effect of weathering processes again.
Origin
g of Sedimentary
y Rocks
Volcanic ejecta
Ground Water
Parent Rock
Decomposition & Leaching
Transportation
Sediments
Ocean Water
Diagenesis
Sedimentary Rocks
Atmosphere
h
Cosmic matter
1
2
3
4
Sedimentary Cycle
I. WEATHERING PROCESSES
Weathering is the breakdown and decomposition of rocks
and minerals (at or near the Earth's surface) by mechanical,
chemical and biological
g
processes into p
p
products that are
more in equilibrium with the conditions found in this
environment.
Weathering itself involves little or no movement or removal
of the decomposed rocks and minerals.
minerals They accumulate
where they form and overlie unweathered bedrock
A) Physical (Mechanical) Weathering
Rock disintegration
g
(p
(physical
y
breakdown))
It is the breakdown of rock materials into smaller and
smaller pieces with no change in their chemical and
mineralogical
g
composition. Processes of Mechanical
Weathering serve to increase surface area, which
enhances chemical weathering.
A) Physical (Mechanical) Weathering
Exfoliation and spheroidal weathering (“sheeting”)
-Process in which Slab-like
layers/sheets of rock are split from
the main rock mass due to reduction
in pressure as a result of removal/
erosion of overlying rocks
-Exfoliation is largely restricted to
granitic
i i rocks.
k
“exfoliation domes”
P
Pressure
release
l
ffracturing
t i
- As uplifting proceeds, the overlying
rocks gradually erode, and thus the
pressure on the underlying rocks
decreases This unloading of
decreases.
pressure causes the rocks to expand
and fracture
A) Physical (Mechanical) Weathering
Expansion/contraction
pa s o /co t act o of
o rock
oc
Alternate thermal heating/cooling as a
result of daily and seasonally changes in
temperatures for long time can cause
fracturing and exfoliation of the rocks. The
surface of the rock expands more than its
i t i
interior.
Abrasion & Collision
Abrasion is the mechanical grinding of rock surfaces by friction and impact of
rock fragments which are carried by moving current and glaciers. Also the
collision between different particles with each other cause their abrasion and
wearing.
A) Physical (Mechanical) Weathering
 Frost wedging
g g
-Repeated cycles of freezing & thawing in Mountainous regions can
break rock into smaller fragments
- It develops
d
l
llarge accumulations
l ti
off lloose angular
l sediments
di
t
beneath cliffs (talus slopes)
Talus Slope
S lt cracking
Salt
ki
• It is formed when salt water penetrates into cracks and evaporates.
This leads to growing of salt crystals in the cracks which causing
expansion of these cracks and pushes the rock apart.
• It is common in desert environment.
B) Chemical Weathering
Rock decomposition
p
((Chemical alteration))
• It is the decomposition of rocks by chemical agents
that can alter and change both their chemical and
mineralogical composition.
• New minerals may be formed
formed.
• Most important agents in chemical weathering: Water,
Carbon dioxide and Oxygen
Factors Controlling Rates of weathering
1. Bedrock characteristics
a Rock Composition:
a.
the rate of weathering of rocks is
related to relative stability of their
mineral composition to chemical
weathering.
Ex. Limestones (calcite) & Sandstones
(quartz).
The more susceptible parts of the rock will weather faster than the
more resistant portions of the rock.
rock This will result in differential
weathering.
b. Particle size
Smaller the particle size the greater the surface
area and
dh
hence th
the more rapid
id the
th weathering.
th i
c. Structure:
Bedding planes, joints, and fractures, all provide
pathways for the entry of water. A rock with these
features will weather more rapidly than a massive
and structureless rock
rock.
2. Topography e.g., gentle or steep slope
On gentle slopes water may stay in contact with
rock for longer periods of time, and thus result in higher weathering rates.
3 Climate: (Temperature
3.
(Temperature, moisture)
Processes of weathering are more rapid in humid and hot climate than
cold or very dry one.
E lilimestones iin a d
Ex.
dry d
desert climate
li
are very resistant
i
to weathering,
h i
b
but
limestones in tropical climate weather very rapidly.
4 Amount of vegetation and organic materials
4.
The more organic mass is in the zone of weathering the more
intensively the chemical decomposition of rocks takes place.
Major Factors Controlling Rates of weathering
B) Chemical Weathering
M i processes off chemical
Main
h
i l weathering:
th i
1. Dissolution
Dissolving of minerals by a liquid agent (i.e. water)
example:
-Halite dissolution NaCl = Na+ + Cl-CaSO4. 2H2O (gypsum) = SO42- + 2H2O
2. Hydration
Hydration involves attachment of H2O or OH- ion to a mineral, resulting
in formation of a new mineral.
CaSO4 (anhydrite) + 2H2O
Fe2O3 (hematite) + H2O
CaSO4. 2H2O (gypsum)
2FeOOH (geothite)
Dehydration involves removal of H2O or OH- ion from a mineral.
B) Chemical Weathering
3. Hydrolysis
3
d l i (water)
(
)
• Hydrolysis represents a substitution of H+ or OH- of water for an ion in
the mineral.
• It is especially effective in the weathering of common silicate minerals.
2KAlSi
S 3O8 + 2H+ + H2O → Al2S
Si2O5(O
O5(OH))4 + 2K+ +4H4S
SiO
O4
(K-Feldspar)
kaolinite (clay mineral)
Kaolinite
B) Chemical Weathering
4 Carbonation (Carbon dioxide
4.
dio ide Hydrolysis,
H drol sis type
t pe of dissolution)
dissol tion)
It is a dissolution due to the reaction of the minerals with carbonate and
bicarbonate ions formed as a result of dissolving of carbon dioxide in water:
CO2 + H2O ↔
H2CO3
H+ +
( b i acid)
(carbonic
id)
Example: Calcite dissolution
CaCO3 + CO2 + H2O
HCO3(bi b
(bicarbonate)
t )
Ca2+ + 2 HCO3- (bicarbonate)
B) Chemical Weathering
5 Oxidation
5.
•
•
•
It is the reaction that occurs between compound and oxygen.
It may react with minerals to change the oxidation state of an ion, which
causes the
th structure
t t
tto b
be lless rigid
i id and
d iincreasingly
i l unstable.
t bl
This is more common in Fe & Mn bearing minerals.
Examples:
E
l
1. Rusting: Iron combines with oxygen (dissolved in water)
to form iron oxide
-4Fe° + 3O2 = 2Fe 2O3 (hematite)
2. Oxidation of organic
g
matter: CH2O + O2 → CO2 + H2O
6. Reduction
It is simply the reverse of oxidation, and is thus caused by the
addition of one or more electrons producing a more stable
p
((reaction with organic
g
carbon.
compound
Fe2O3 . H2O (limonite) + C → FeCO3 (siderite)
C) Biological Weathering
Weathering of rock from activities of:




organisms
plants roots
p
burrowing animals
humans
Products of Weathering
1. Solid particles





Formed from mechanical weathering of parent rocks
differ in grain size (gravel, sand, silt, clay).
Accumulations of these products called clastic or detrital sediments.
Th include
They
i l d quartz
t and
d feldspar
f ld
and
d allll ttypes off rock
k ffragments.
t
They form clastic rocks such as sandstones, conglomerates, mudrocks
or form soils.
Gravel
Conglomerate
Sand
Sandstone
Mud
Shale
Products of Weathering
2. Soluble materials
2 , Na+, CO 22
2
2 Ions or molecules such as (Ca
(C 2+
3 , SO4 ,..)) dissolved in water.
 They removed through chemical weathering
 They produce some chemical and biochemical rocks such as:
evaporites, chert, limestones.
Ca+2
Na+
Mg+2
Fossiliferous L.S.
CO3-22
Coral L.S.
Flint
Rock Salt
Products of Weathering
3. Secondary
y minerals
 Neoformed minerals, which are formed after chemical
weathering and alteration of some minerals.
E chemical
Ex.,
h i l weathering
th i off ffeldspars
ld
produces
d
clay
l
minerals,
aluminum hydroxides, ferric oxides.
2KAlSi3O8 + 2H+ + H2O → Al2Si2O5(OH)4 + 2K+ +4H4SiO4
(K-Feldspar)
(kaolinite)
 Oxidation of Iron to hematite, limonite,..
4Fe° (Iron) + 3O2 = 2Fe 2O3 (hematite)
Products of Weathering
4. Soil
 loose, uneroded sediment material
(residual materials).
 It is a product of mechanical and
chemical weathering of rock plus
addition of organic material
material.
Soil Profile
O Horizon – decayed and loose organics (topsoil)
A Horizon - inorganic
g
mineral p
particles mixed with
some organics
B Horizon – clays with little organics
C Horizon – transition between bedrock and soil
 The most common residual deposits are
- Bauxite (aluminium ore)
ore),
- Laterite (iron-rich soil).
-Calcrete, Ferricrete
Decomposition of Main Minerals in Igneous Rocks
Original Minerals
Weathering
Process
New Mineral
Material
Washed Away
In Solution
Fe, Mg minerals: H2CO3 alteration,
olivine,
oxidation
pyroxene
pyroxene,
amphibole
Clay
minerals,
Fe oxides
Fe-oxides
Mg, Ca, Si
Feldspars
H2CO3 alteration
Clay
Minerals
K Na,
K,
Na Ca
Quartz
Little change
change,
some dissolution
none
Si
Calcite
Dissolves easily
none
Ca
Weathering
of Granite
Quartz
Clay Minerals
+
Mg, Ca, Si
Clay Minerals
+
K, Na, Ca
II. Erosion and Transportation
* Erosion is the removal of weathered material from the site of
weathering.
* Transportation is the movement of weathered material from
the site of weathering to the site of deposition
deposition.
• The weathering products may still located in situ and not
transported or undergone variable long or short transportation.
• Mostly,
Mostly no chemical changes take place for the sediments
during transportation processes but many physical changes may
occur as in rounding of particles, sorting of sediments and
particle
ti l sizes.
i
The major natural agents of erosion and transportation are
gravity, wind, running water, glaciers, waves, and rain.
Wind
Gravityy
Rockslide
Glacial
Rock fall from a
steep slope or cliff
cliff.
River
Beach
Transport Mechanisms:
Suspended
p
Load: Fine-grained
g
sediment ((clay
y and silt))
transported in suspension due to turbulence
Bed (or traction) Load: Coarse-grained
Coarse grained sediment (sand and
gravel) transported on the bottom of the stream
bed by rolling and sliding
Saltation: Sediment (typically sand) transported by
intermittent jumps
Solution: as dissolved particles (soluble ions and molecules
i water)..
t )
in
Factors Affecting Transportation of Sediments:
1. Agent of transportation:
- Glaciers transports all sizes together and deposit angular and
poorly sorted sediment.
- Wind transports clay
clay-sand
sand size sediments and deposits rounded
and well sorted sediments.
2. The average velocity (speed) of the flow.
As the velocity of the flow increases, the size of the particles
carried in the flow also increases
increases.
3. Distance of transportation
Long transportation of sediments by water and air causes:
 more abrasion of the grains (more
rounded).
 wellll sorting
i (coarse
(
particles
i l are
transported for short distance and
deposited near the source, but the
fine particles are transported for long
distance and deposited far from the
source).
III. Deposition
Deposition is the accumulation and settling of sediment in the
basin of deposition (ocean, lakes, lagoons, inland valleys) as
layers
y
of loose sediment. This p
process is called a
sedimentation
Depositional
D
iti
l environment
i
t
- A geographic setting where sediment is accumulating
(deposited).
(deposited)
- Each setting is characterized by a particular combination of
geologic processes
- The geologic setting may change with time (e.g. marine to
continental)
- By studying present day environments, geologist can more
easilyy interpret
eas
te p et the
t e rock
oc record
eco d a
along
o g tthe
e geo
geologic
og c ttime.
e
How can determine the type of Depositional Environment?
It can be
b determined
d t
i db
by llooking
ki att
– Texture (grain size, shape and composition, etc..)
– sedimentary structures
– fossils content,
– bed shape and vertical sequences within the
sedimentary layers
• Sedimentary
Facies
It is a body of sedimentary rock accumulated and modified in a
particular environment.
Each facies is characterized by features (sediment composition
(
(lithology),
) grain size, texture, sedimentary structures, ffossil content
and colour) that distinguish it from other facies
How can Depositional environment affect the rock Facies?
physical attributes such as:
• Water type and depth
• degree of agitation
• affect and control the living
organisms or type of the
sediment.
Chemical factors such as
• Eh and pH of water
• salinity
• affect organisms and
control mineral
precipitation.
• Shape and location of
basin of deposition
• Plate tectonic
• topography
• affect the
composition fossil
composition,
contents, and
textures
Depositional Settings
Continents: Desert, glacial, fluvial (rivers), lake, swamp, cave
Mixed (Transition zone): Lagoon, river delta, beach, tidal flat
Marine : Reefs, continental shelf, continental slope, deep water
Delta
Desert
Beach
Ocean
Swamp
Lakes
Continental Sedimentary Environments
1. Glacial ‐‐ deposits may have wide range of grain sizes (poorly sorted). made of glacial till.
(poorly sorted). made of glacial till.
2. Fluvial 2
Fluvial ‐‐ migration of ripples/dunes on riverbed produces X
migration of ripples/dunes on riverbed produces X‐
stratification in deposits (mud and sand).
3. Lacustrine ‐‐ deposition of mud, thin layers on lakebed; in arid regions forms evaporites
4. Aeolian ‐‐ large wind‐blown sand dunes produces thick cross‐stratification in deposits
5. Streams: deposit clastic sediments in streambeds, in
floodplain, and on deltas.
Marine (Nearshore) & Transtional Environments
1 D lt
1. Deltas ‐‐
where rivers meet the sea ‐‐
h
i
t th
clastic
l ti sediments are di
t
deposited 2 Beaches deposits of sand (siliciclastic
2. Beaches ‐‐
deposits of sand (siliciclastic &carbonate) at the &carbonate) at the
coast 3 Shelf ‐‐ may be sand and mud or carbonate sediments 3. Shelf may be sand and mud or carbonate sediments
4. Reefs ‐‐ build‐up of limestone from coral skeletons Marine (Offshore) Sedimentary Environments (Deep Sea)
1 Shelf ‐‐ carbonates 1. Shelf ‐‐
carbonates
2. Slope and rise ‐‐ mixed carbonates/clastics
3 Deep marine ‐‐ finely layered mud
3. Deep marine ‐‐
finely layered mud
IV. Lithification
Turning sediment into rock
Diagenesis = chemical, physical, and
biological changes that take place to
sediment
di
t after
ft it is
i deposited.
d
it d It includes
i l d
low temperature near-surface processes to
higher temperature subsurface processes
(<300C and 1-2 kb)
Lithification is a diagenetic process that refers collectively to all the
processes that
h convert loose
l
sediment
di
to hard
h d sedimentary
di
rocks.
k
loose sediment
hard sedimentary
rock
IV. Lithification
Turning sediment into rock
Main Lithification Processes:
1. Compaction
for sediments with clastic texture
2. Cementation
3. Recrystallization
for chemical crystalline sediment
•
Burial
Lithification requires
increased pressures
and temperatures
p
(with depth)
1. Compaction
• It is a physical process of lithification by which buried sediment is
reduced in volume by pressure from the weight of overlying sediments.
•With compaction:
p
- the air and water between the grains are
expulsed
- the pore space is reduced
-the loose sediment is converted into more
cohesive rock.
•Compaction affects all sediments, but
changes are most pronounced in finegrained
i d clastic
l ti sediments,
di
t such
h as clays
l
and silts.
•Burial of a clay may result in
a 40% reduction in volume
Burial
2. Cementation
• Cementation is the most important
p
p
process for turning
g sediments to rock.
• It is the process by which sediment grains are bound together by minerals
chemically precipitated from water circulating through sediment.
• These cementing materials are precipitated in the pore spaces and cement
the grains together.
• Coarse-grained sediments, such as gravels and sands, are more likely to be
cemented than fine
fine-grained
grained sediments
sediments.
• The most cementing materials are: Silica, Calcium carbonate, Iron oxides.
3. Crystallization & Recrystallization
The process of formation of the chemical rocks with interlocked crystalline
texture is called crystallization process.
Recrystallization
y
is a p
process in which the texture
within the less stable minerals reorganizes and
develop into new, more stable and more interlocked
crystals with more size in solid state by the effect of
heat and pressure with depth and the movement of
fluids within pore spaces .
Examples:
• Amorphous silica to coarse crystalline quartz
• fine lime mud into coarse sparry
p y calcite
• recrystallization of aragonite (unstable form of CaCO3) to calcite (more
stable form of CaCO3).
Aragonite
Calcite
V. Uplift
It the process of uplifting of the rocks by the effect of
tectonic movements. It leads to the exposing of the rocks
t the
to
th effect
ff t off weathering
th i processes again.
i
Simple Model for the Evolution of Sedimentary
Rocks
1 Weathering
1.
2. Erosion
3 Transport
3.
4. Deposition
5. Compaction / Cementation
6. Uplift
Source area (any preexisting rock)


Ch mi l weathering
Chemical
th in
Weathering products
 Clay minerals
 Ions and
d
compound in solution
Transportation
 Precipitation from solution
 Used by organisms

Physical weathering
Weathering products
 Gravel, sand, silt and clayclaysized particles

Transportation

Deposition (non(non-detrital
sediments)

Deposition (detrital sediments)

Lithification

Lithification
Chemical & Biochemical
sedimentary rocks
(e.g. limestone)


Detrital sedimentary rocks
(e.g. sandstone)