15. IGNEOUS SEDIMENTARY METAMORPHIC
030201Molten materials
in deep crust and
upper mantle
Weathering and
erosion of rocks
exposed at surface
Rocks under high
Temperatures and
pressures in crust
Eng. El sayed Amer 15
18. 01
Igneous rock
01
02
Intrusive
(solidifies underground)
Extrusive
(volcanic eruption)
• Comprise 95% of the Earth's crust.
• Originated from the solidification of molten material from deep inside the Earth.
There are two types:
• Volcanic - glassy in texture due to fast cooling.
• Plutonic - slow-cooling, crystalline rocks.
Eng. El sayed Amer 18
21. Country
rock
Volcano
Lava flow Ash falls and pyroclasts
Volcanic neck with
radiating dikes
Stock
Sill
Sill
Sill
Dikes cut
across layers
of country
rock…
…but sills run
parallel to them.
Batholiths are the largest
forms of plutons, covering
at least 100 km2.
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24. Rocks formed by the transformation, in the solid state, of pre-existing
igneous or sedimentary rocks as a result of high temperature and
pressure
Examples are
• Marble - formed from limestone
• Hornfels - from shale or tuff
• Gneiss - similar to granite but formed by metamorphosis
Metamorphic rock2
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27. These are the most important for the oil industry as it contains most of the
source rocks and cap rocks and a majority of the reservoirs.
Sedimentary rocks come from the debris of older rocks and are split into
two categories
• Clastic and Non- Clastic.
• Clastic rocks - formed from the materials of older rocks by the actions of
erosion, transportation and deposition.
Non- Clastic rocks - from chemical or biological origin and then deposition.
Sedimentary rock3
Eng. El sayed Amer 27
28. Clastic
Rock type Particle diameter
• ConglomeratePebbles 2 - 64mm
• Sandstone Sand .06 - 2mm
• Siltstone Silt .004 - .06mm or 4 to 65 microns
• Shale Clay < .004mm or 4 microns
Non- Clastics
Rock type Composition
• Limestone CaCO3
• Dolomite CaMg(CO3)2
• Salt NaCl
• Anhydrite CaSO4
• Gypsum CaSO4.2H2O
• Coal Carbon
Sedimentary rock3
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50. Petroleum System
A petroleum system includes all those geological
elements & processes that are essential for an oil
deposit to exist in nature.
These basic elements are:
1. Petroleum Source rocks
2. Migration Paths
3. Reservoir rocks
4. Seals
5. Traps
And the geological processes
that created each of them
Generation
Migration
Accumulation
Preservation
Source Rock
Migration Route
Reservoir Rock
Seal Rock
Trap
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52. 01
GENERATION
GENERATION:
• The process by which solid organic matter present in the source
rocks is transformed into liquid or gaseous hydrocarbons
• Oil window : 60-120 degree Celsius
• Gas window: 120 – 180 degree Celsius
• Burial Depth: 2.5 – 3km depending on the geothermal gradient
and kerogen type
53. 02
MIGRATION
• The process of petroleum migration is
divided into 3 parts
1. Primary migration: Movement of
hydrocarbons from source rock into the
reservoir rock (expulsion)
2. Secondary migration: Subsequent
movement of hydrocarbons within the
reservoir rock whereby the oil and gas
has left the source rock and entered the
reservoir rock
3. Tertiary migration: Occurs when the
seal above the reservoir breaches;
resulting in a probable petroleum seep
to the surface
57. • To have a complete petroleum system, we need rocks that
will form:
Source
Rocks
Reservoir
Rocks
Cap
Rocks
From which oil and gas will
be generated; essentially
rich with kerogen
Impermeable rocks that
will keep oil and gas within
the reservoir
Porous and permeable
rocks in which oil and gas
will accumulate over time
59. Source
Rock
Rich in organic matter
From which oil and gas will be generated;
essentially rich with kerogen
Porous Permeable oldest Deeper
59
60.
61. Reservoir
Rock
which oil and gas will accumulate
over time
Oil and gas are trapped in the pore spaces of rock
Porosity is an indication of how much empty
space there is in rock
Porous Permeable
61
62. The Reservoir
• A reservoir is a porous rock which contains fluids
• The reservoir has porosity and permeability
Cap rock
Reservoir
Source
Migrating hydrocarbons
Oil
Water
Gas
63. Reservoir Rocks
Almost all reservoir rocks are sedimentary.
Sedimentary rocks include:
Sandstone
Conglomerate
Limestone
Dolomite
Sand
Loose, uncompact (unconsolidated).
Conglomerate
A cemented Clastic rock containing rounded rock fragments of gravel,
pebble size.
Limestone
Formed chiefly by accumulation of shells and coral
Consists mainly of calcium carbonate
65. 2017 Presentation Template
www.website.com
Porosity The percent volume of pore space
a fluid’s ability to flow through
a porous media
Porosity varies relative to grain shape and arrangement.
Normally porosity varies between 10% and 30%.
Porosity is the ratio of the void space in a rock to the bulk
volume or size of the rock.
66. Effect of Formation Water
Formation water wetting
the sand grains
Pore
Space
Sand Grain
Quartz
Limestone
Chert
Feldspar
Quartz
Quartz
Quartz
Clay
Clay
69. Permeability
Permeability is the ability of a rock to transmit a fluid.
It is measured in millidarcies (md).
Permeability is a function of area, length, pressure,
viscosity, and flow rate of the fluid.
Formations cannot be produced if permeability is less
than 50 md.
70. Trap
Oil will be trapped
The location of a subsurface obstacle to the migration
of petroleum towards the surface of the earth.
70
72. Traps
Structural Traps
Result from rock layer deformation.
Stratigraphi
Result when a reservoir bed is sealed by other beds
Result when porosity or permeability change within a
reservoir bed.
Structural
Stratigraphic
Lens
Unconformity
Pinch out
Porosity Trap
Anticline
Syncline
Fold
Fault
Salt Dome
73. Structural
• Structural traps form because of deformations in the rock such as a
fault or anticline
• Fault trap• Anticline
74. • are formed when other beds seal the reservoir bed or permeability
changes within the reservoir bed
• Fault trap• Anticline
Stratigraphic