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Transcript of MG672 Oil and Gas Management 1
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MG672 Oil and GasManagement
Global oil & gas industry
Oil and Gas formation &reserves
Origin of Petroleum
Ancient, and Less Ancient, Times
Small amounts of petroleum have been used
throughout history.
The Egyptianscoated mummiesand sealedtheir mighty Pyramidswith pitch.
The Babylonians, Assyrians, and Persiansused it to pave their streetsand hold their
wallsand buildingstogether.
Origin of Petroleum
1000 A.D. Arab scientists discovered
distillation and were able to make kerosene.
This was lost after the 12 thcentury!
Rediscovered by a Canadiangeologist called
Abraham Gesner in 1852
Origin of Petroleum
3000 BC: Fertile Crescent & Baku Seeps
Oil seeps noted along banks of Euphrates
AzerbaijanPersias land of fire
Ancient Persians and Sumatransalsobelieved petroleum hadmedicinal value.
Boatsalong the Euphrates were constructedwith woven reeds and sealed with pitch.
Origin of Petroleum
The Chinese600 BC also came across it while
digging holes for brine (salt water) and used
the petroleum for heating.
They burned the gas to evaporate brine for
salt.
The Bible even claims thatNoahused it tomake his Ark seaworthy.
American Indiansused
petroleum for paint, fuel, andmedicine.
Desert nomadsused it to treatcamels for mange, and the HolyRoman Emperor, Charles V, usedpetroleum it to treat hisgout.
Origin of Petroleum
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1291 AD: Marco Polos Journey
Caspian oil produced for medicine, lamps
Brought back sample of oil from Sumatra
This seemed a popular idea, and up through the
19thCentury jars of petroleum were sold as
miracle tonicable to cure whatever ailed you.
People who drank this "snake oil" discovered
that petroleum doesn't taste very good!
Origin of Petroleum The Search for Oil
Yet despite its usefulness, for thousands ofyearspetroleum was very scarce.
People collected it when it bubbled to thesurface or seeped into wells.
For those digging wells to get drinking water
the petroleum was seen as a nuisance.
However, some thought the oil might have
large scale economic value.
George Bissell
George Bissell is often consideredthe father of the American oilindustry
Bissell had the innovative idea ofusing this oil to produce kerosene,then in high demand.
he and his partner, JonathanEveleth, formed the PennsylvaniaRock Oil Company for this
purpose.
After getting confirmation of the usefulness ofthe product from Yale chemist Benjamin SillimanJr., in 1854Bissell and a friend formed theunsuccessful Pennsylvania Rock Oil Company.
In 1858Bissell and a group of business menformed the Seneca Oil Company.
They hired an ex-railroad conductor namedEdwin Draketo drill for oil along a secluded
creek inTitusville Pennsylvania.
Colonel Drake
In 1856, after seeing pictures ofderrick drilling for salt, Bissell
conceived of the idea of drilling for oil,rather than mining it.
This was widely considered ludicrousat the time but on August 27, 1859,the company first succeeded in strikingoil, on a farm in Titusville,Pennsylvania.
Bissell invested heavily in thesurrounding region and ended upbecoming a wealthy business man.
The company's agent, Edwin Drake, issometimes credited with the"discovery" of oil.
Pennsylvania's "Black Gold"
Drake's well produced only thirty-five barrelsa day, however he could sell it for $20 abarrel.
News of the well quickly spread andbroughtdroves of fortune seekers.
Soon the hills were covered with prospectorstrying to decide where to dig their wells.Some used Y-shaped divining rodsto guidethem.
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Pennsylvania's "Black Gold"
To dig the wells six-inch wide cast iron pipeswere sunk down to the bedrock.
A screw like drillwas then used to scoop out dirtand rock from the middle.
Many discovered to their dismay that once theyhit oil they had no way to contain all of it.
Until caps were added to the wells vastquantities of oil flowed into the appropriatelynamedOil Creek.
The First Pipeline
Transporting the oil was also a problem.
In 1865 Samuel Van Syckel, an oil buyer,began construction on a two-inch widepipelinedesigned to span the distance to therailroad depot five miles away.
Theteamsters, who had previouslytransported the oil, didn't take to kindly toSyckel's plan, and they used pickaxes to breakapart the line.
Eventually Van Syckel brought in armedguards, finished the pipeline, and made aton-o-money.
By 1865wooden derricks extracted 3.5million barrels a yearout of the ground.
Such large scale production caused the price
of crude oil to plummet to ten cents a barrel.
How Much Oil?
Andrew Carnegiewas a large stockholder in
the Columbia Oil Company.
Carnegie believedthat the oil fields wouldquickly run drybecause of all the drilling.
He pe rsuaded Columbia Oil to dig a hugeholeto store100,000 barrels of oilso thatthey could make a killing when the country's
wells went dry.
Luckily there was more oil than theythought!
But don't fee l too sorry for Carnegie, hedidn't let the setback slow him down very
much, and went on to make his millions inthe steel industry.
http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=tM4auxwf0E9jJM&tbnid=U1BxxXxmWU4GvM:&ved=0CAUQjRw&url=http://rewild.info/anthropik/2007/05/the-alleghenys-black-gold/index.html&ei=gLttUrrxNfaj4APnn4CwDg&bvm=bv.55123115,d.dmg&psig=AFQjCNEzkR15cc1WmPgln9urqXDc9VNUew&ust=1383009522745809 -
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In contrast, "Colonel" Drakewas committed tothe oil business.
He scoured the country looking for customerswilling to buy his crude oil.
However, the bad smell, muddy black color, andhighly volatile component, called naphtha,caused few sales.
It became obvious that one would have to refinethe oil to find a market.
Early Refining
By 1860there were 15 refineriesin operation.
Known as "tea kettle" stills, they consisted of a
large iron drumand a long tubewhich acted as
a condenser.
Capacity of these stills ranged from 1 to 100
barrels a day.
A coal fireheated the drum, and three fractions
were obtained during the distil lation process.
The first component to boil off was the highly
volatile naphtha.
Next came the kerosene, or "lamp oil", andlastly came the heavy oils and tar which weresimply left in the bottom of the drum.
These early refineries produced about75%kerosene, which could be sold for high
profits.
Kerosene was so valuablebecause of a whale shortagethat had began in 1845dueto heavy hunting.
Sperm oilhad been the mainproduct of the whalingindustry and was used inlamps.
Candleswere made withanother whale product called"spermaceti".
This shortage of natural sources meant that
kerosene was in great demand.
Almost all the families across the countrystarted using kerosene to light their homes.
However, the naphtha and tar fractionswere
seen as valueless and weresimply dumpedinto Oil Creek.
Laterthese waste streams were converted
into valuable products.
In 1869 Robert Chesebrough discovered howto make petroleum jellyand called his newproduct Vaseline.
The heavy componentsbegan being used aslubricants, or as waxesincandlesandchewing gum.
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Tarwas used as a roofing material. But the morevolatile componentswere still without much
value. Limited success came in using gasolineas a local
anestheticand liquid petroleum gas(LPG) in acompression cycle to make ice.
The success in refined petroleum productsgreatly spread the technique.
By 1865there were 194 refineriesin operation.
John D. Rockefeller
In 1862John D. Rockefellerfinanced hisfirstrefineryas a side investment.
He soon discovered that he liked thepetrole um industry, and devoted himself to itfull time.
As a young bookkeeperRockefeller had cometo love the order of a well organized ledger.However, he was appalled by thedisorderand instabilityof the oil industry.
Anyone could drill a well, andoverproductionplagued the e arly industry.At times this overproduction meant that thecrude oilwas cheaper than water.Rockefeller saw early on, that refining andtransportation, as opposed to production,were the keys to taking control of theindustry.
And control the industry he did!
In 1870he establishedStandard Oil, whichthen controlled 10% of the refining capacity
in the country.
Transportationoften encompassed 20% ofthe total production cost and Rockefeller
made under-the-table dealswith railroadstogive him secret shipping rebates.
This cheap transportation allowed Standard
to undercut its competitorsand Rockefellerexpanded aggressively, buying outcompetitors left and right.
Soon Standard built a network of "iron
arteries" which delivered oil across the
Eastern U.S.
This pipeline systemrelieved Standard's
dependence upon the railroads and reduced itstransportation costs even more.
By 1880Standard controlled 90% of thecountry's refining capacity.
Because of its massive size, it brought securityand stabilityto the oil business, guaranteeingcontinuous profits.
With Standard Oil, John D. Rockefellerbecamethe richest person in the World
http://www.google.com.cy/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=bi7Cx1YF6XgSlM&tbnid=2KvvLEPao-DWvM:&ved=0CAUQjRw&url=http://thepublici.blogspot.com/2010/06/to-light-one-candle.html&ei=pEtOUp-zEcKNtQafkoHoAQ&bvm=bv.53537100,d.d2k&psig=AFQjCNGBa_TD1vhlvVRBD0oUpUfaXfX2AQ&ust=1380949082741887http://www.google.com.cy/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=bi7Cx1YF6XgSlM&tbnid=2KvvLEPao-DWvM:&ved=0CAUQjRw&url=http://thepublici.blogspot.com/2010/06/to-light-one-candle.html&ei=pEtOUp-zEcKNtQafkoHoAQ&bvm=bv.53537100,d.d2k&psig=AFQjCNGBa_TD1vhlvVRBD0oUpUfaXfX2AQ&ust=1380949082741887 -
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Origin of petroleum
The great compositional complexity of
petroleums (this term includes both oil and
gas) reflects the combined effects of allprocesses involved in the origin of petroleum
accumulations and their fate during long
periods of geological time.
Since relevant geological and geochemical
conditions under which these processes
proceed can vary from place to place, thecomposition of petroleums are subject to
great variations.
As a general rule, the origin of petroleum is
neve r in the reservoir accumulation from
which it is produced.
Instead, petroleums have e xperienced a long
series of processes prior to accumulation in
the reservoir.
Fig. 1. Main geological conditions and geochemical processes requiredfor the formation of petroleum accumulations in sedimentary basins:
1) petroleum generation in source rocks;2) primary migration of petroleum;3) secondary migration of petroleum;4) accumulation of petroleum in a reservoir trap;
5) se epage of petroleum at the Earths surface as a consequence of afractured cap rock.
Petroleum accumulation forms in sedimentary
basins and can be discovered by exploration, if
the following geological conditions are met:
Occurrence of source rocks which generatepetroleums under proper subsurface
temperature conditions.
Sediment compaction leading to expulsion of
petroleum from the source and into the
reservoir rocks (primary migration).
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Occurrence of reservoir rocks of sufficient
porosity and permeability allowing flow of
petroleum through the pore system(secondary migration).
Structural configurations of sedimentarystrata whereby the reservoir rocks form
traps, i.e. closed containers in the subsurface
for the accumulation of petroleum.
Traps are sealed above by impermeable
sediment layers (cap rocks) in order to keep
petroleum accumulations in place.
Correct timing with respect to the sequence bywhich the processes of petroleum generation
/migration and trap formation have occurredduring the history of a sedimentary basin.
Favourable conditions for the preservation ofpetroleum accumulation during extendedperiods of geologic time, i.e. absence ofdestructive, such as the fracturing of cap rocksleading to dissipation of petroleumaccumulations, or severe heating resulting in thecracking of oil into gas.
The question of the origin of petroleum hasbeen hotly debated for a long time.
A great many theories, hypotheses andspeculations have been proposed.
Decades ago, various ideas on a possibleinorganic origin of petroleum were broughtforward, e .g. that it results from the reactionof iron carbide with water deep in the Earthscrust.
The main evide nce supporting these theories
was the occasional occurrence of
hydrocarbon fluid inclusions and solidbitumens in igneous rocks as well as a few
cases of oil and gas fields hosted in fractured
basement rocks (e.g. granites, basalts, and
metamorphic rocks).
However, in most of these cases it could be
demonstrated that the petroleum materials wereultimately generated in sedimentary rocks and hadbeen transported, e.g. by convective flow ofmineralising aqueous fluids, into the granites, or thatthe y had migrated from sedimentary strata over longdistances to accumulate in fractured basement rocks.
These cases of petroleums occurring in basementrocks are extremely rare and not commerciallyimportant when compared to the vast majority ofhydrocarbon reserves in sedimentary basins (Selley,1998).
One of the main arguments concerns the
ubiquitous occurrence of biological markermolecules in petroleums, such as porphyrines,steranes and hopanes.
The highly specific carbon structures of thesemolecules could not be synthesized by inorganicreactions.
They are clearly and uniquely derived frommolecular structures synthesized by livingorganisms.
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Today, the evidence in favour of an organic origin ofpetroleum is overwhelming.
One of the main arguments concerns the ubiquitousoccurrence of biological marker molecules inpetroleums, such as porphyrines, steranes andhopanes.
The highly specific carbon structures of thesemolecules could not be synthesized by inorganicreactions.
They are clearly and uniquely derived from molecularstructures synthesized by living organisms.
Petroleum source rocks
Petroleum source beds are fine grained, clay-
rich siliclastic rocks (mudstones, shales) or
dark coloured carbonate rocks (limestones,marlstones), which have generated and
effectively expelled hydrocarbons.
A petrole um source is characterised by three
essential conditions:
1. it must have a sufficient content of finelydispersed organic matter of biological origin;this organic matter must be of a specificcomposition, i.e. hydrogen-rich;
2. the source rock must be buried at certaindepths and
3. subjected to proper subsurface temperatures inorder to initiate the process of petroleumgeneration by the thermal degradation of
kerogen.
Based on e mpirical evidence, minimumconcentration levels of 1.5% and 0.5% totalorganic carbon (TOC) in source rocks ofsiliclastic and carbonate lithologiesrespectively have been established (Hunt,1996).
The organic carbon concentration is anapproximate measure of the organic matter
content of a rock.
Organic matter is predominantly composed of organic
carbon, but also contains minor amounts of hetero-elements (N, S, and O).
This minimum concentration of organic carbon insource rocks is controlled by the relationship betweenthe quantity of petroleum generated and the internalstorage capacity of the rocks in terms of theirporosity.
If too l itt le organic matter is present, the smallquantities of petroleum generated will not exceed thestorage capacity of the rock, i.e. no petroleumexpulsion will take place.
Most source rocks which have effectively generated
and expelled commercial quantities of petroleumhave TOC concentrations in the order of 2-10%.
An example of a prolific source rock of siliclasticlithology is the Upper Jurassic Kimmeridge ClayFormation in the North Sea Basin which has generatedmost of the oil accumulated in many large fields inthat area.
It has TOC contents ranging mostly between 5 and12% (Bordenave et al., 1993).
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A good-quality petroleum source rock of carbonatelithology is exemplified by the Triassic-age MerideLimestone, which is the source of the oil present in
several fields in the Po valley area of northern Italy. Its TOC content varies mostly between 0.5 and 1.5%
(Leythaeuser et al., 1995).
The reason why petroleum source rocks of carbonatelithologies tend to have significantly lower TOCconcentrations has to do with the quality andcomposition of the organic matter present.
In carbonate source rocks, the organic matter tends tobe richer in hydrogen.
Most petroleum source rocks display dark
brown to black colours. This is due to the
presence of finely disseminated organicmatter as well as finely dispersed pyrite
crystals (FeS2).
2 cm section seen
under a microscope
Basic Depositional Scenarios
There are three basic depositional scenarios
which ensure favourable conditions for the
prese rvation of organic matter.
1. The stagnation model requires a silled basin,
i.e. a marine basin which has highly
restricted water c irculation with the open
ocean (Fig. 3 A).
The Stagnation Model
This is the case today, e.g. of the Black Sea which is upto 2 ,500 m deep but only has a narrow 25 m deep
connection to the Mediterranean Sea. Due to the high input of freshwater from rivers, surface
waters of the Black Sea have lower salinity levels.
Below the halocline lies a huge, stagnant
water mass which provides favourable
conditions for the preservation of deadbodies of algae that settle down from the
surface interval where there are light and
nutrients for their growth (bioproductivity).
Productivity Model
The second principal depositional system in
this context is the so-called productivity
model (Fig. 3 B).
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Wherever they encounter major topographicelevations they displace nutrient-rich bottom
water masses towards the surface of theocean.
In this way, a series of processes and effectsare initiated which are similar to those in theupwelling regime leading to theestablishment of an open-ocean oxygen-minimum zone.
Wherever this oxygen minimum zone
impinges on a continental shelf, organic
matter-rich sediments are deposited.
Such conditions can be observed in todays
oceans, e.g. along parts of the deep shelf
offshore India and Pakistan.
What has been described here in terms oftype of organic matter input for marinesediment systems applies in a similar way togreat lakes on the continents, e.g. the lakes inthe East African Rift Valley.
Biomass derived from freshwater algae andbacteria is deposited in dysaerobic oranaerobic bottom waters of deep lakes, the
water masses of which never get overturned.
All the depositional environments of marine andfreshwater systems can also receive an input oforganic matter derived from higher land plantstransported by rivers or glaciers, or wind-blown.
In contrast to algal or bacterial biomass which isrich in hydrogen, land plant-derived organicmatter tends, due to high contributions bycellulose and lignin-derived precursor materials,
to be rich in oxygen.
Kerogen
The solid organic matter in source rocks which
is insoluble in low-boiling organic solvents is
called kerogen.
Kerogen is partly formed by the accumulation
of resistant macromolecular substances of
biological origin such as cellular lipids, algae
cell walls, membranes, cuticles, spores and
pollen, etc.
Diagenesis
Other parts of kerogen are formed in sedimentsduring a process called diagenesis: The geochemical and mineralogical processes that
occur within the topmost interv al of a sedimentarycolumn.
Organic matter is synthesized by living organisms inthe form of biopolymers such as carbohydrates,proteins, lignin, etc.
Kerogen is, however, not a polymer in a strictchemical sense, rather a complex mixture ofhigh molecular weight substances.
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The main building blocks are polycondensed
aromatic ring-systems with attached aliphatic
side chains of various lengths which areinterconnected by a variety of functional groups,
such as esther, ketone and sulphide-bridges. In
summary, kerogen consists of a physical mixture
of diagenetically restructured biomass as well as
preserved biosynthesized compounds (Killops
and Killops, 1993).
A useful and initial geochemical approach fordetermining the complex composition ofkerogen is by elemental analysis andconsideration of the relationship between theatomic hydrogen/carbonratio H/C and theatomic oxygen/carbon-ratio O/C (F ig. 4).
The high H/C-ratio of type I-kerogens, goes backto a high input of algae and bacterial biomass
and
van Krevelen diagram
Evolutionary pathways
In this way, thegreat varietyof kerogensoccurring innature can beclassified intothree broadcategoriesreferred to astype I-, type II-and type III-
kerogens.
Fig. 4. Variation of elemental composition of naturallyoccurring kerogens in terms of their atomic H/C- and O/C-ratios
Classification of kerogens into three broad categories.
Elemental composition of organic matter in freshlydeposited sediments is plotted towards the upper rightend of each field (diagenesis stage).
With increasing burial, kerogen transformation proceedsduring the catagenesis and metagenesis stages.
Fig. 5. Diagram to
illustrate the main
conditions andproce sses for
kerogen formation
from biological
precursor materials
and kerogen
transformation into
petroleum products
with increasing
maturation
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Petroleum generation
Oil and gas are generated by the thermal
degradation of ke rogen in the source beds.
With increasing burial, the temperature inthese rocks rises and, above a certain
threshold temperature, the chemically labile
portion of the kerogen be gins to transform
into petroleum compounds.
The main reaction mechanism is the breaking
of carbon-carbon bonds (cracking), which
requires that the input of thermal energyexceed certain minimum levels (activation
energy).
Activation energies vary according to the
position and type of carbon-carbon bond
within the kerogen structure.
At higher temperature levels, petroleum
compounds are generated by the cracking of
carbon-carbon bonds within the kerogenstructure in such a way that long aliphatic
side chains and saturated ring structures are
removed from it.
These reactions result in gradual changes in
the elemental composition of the kerogen,
especially in a decrease of its hydrogencontent.
These changes are expressed in the van
Kre velen diagram for each kerogen type as
trend lines, the so-called evolutionary
pathways (see again Fig. 4).
The generation of oil and gas in source rocks
is a natural consequence of the increase of
subsurface temperature during geologic time.
The process of kerogen transformation with
increasing temperatures is called maturation,
which is subdivided into the catagenenis and
metagenesis stages
With respect to the stage to which petroleum
generation has advanced, the organic matter
is labeled immature prior to the onset ofhydrocarbon generation, mature if
hydrocarbon generation is in progress, or
over mature when these reactions have been
terminated.
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Heat is the main driving force in maturation
and petroleum generation reactions.
oil window
The temperature interval where oil
generation is in progress is referred to as the
liquid window or oil window.
It extends over the temperature interval of
about 80-150C.
B. Formation of Oil
Diagenesis
Surface to about km, T , 50C; CH4
Catagenesis
50 to 150C, P about 1.5 kb
Compaction of sediment, expulsion of water
Organic matter becomes kerogen and liquidpetroleumbiogenic gas decreases, howeversome formed by thermal crackingof kerogen
Wet gas: methane+ethane+propane+butane
B. Formation of Oil
Metagenesis
Greater than 4 km, and 150C
Dry gas
C rich residue
Graphite developed
Origin (1): Chemistry
Crude Oil
Hydrocarbon
en.wikipedia.org/wiki/Image:Octane_molecule_3D_model.pngen.wikipedia.org/wiki/Image:Petroleum.JPG
Oil and gas are made of a mixture of
different hydrocarbons.
As the name suggests these are large
molecules made up of hydrogenatoms
attached to a backbone of carbon.
Origin (2): Planktoncache.eb.com/eb/i mage?id=93510
en.wikipedia.org/wiki/Image:Copepod.en.wikipedia.org/wiki/Image:Ceratium_hirundinella.jpg
Most oil and gas starts life as microscopic plants and animals
that live in the ocean.
Plant plankton Animal plankton
10,0
00ofthesebugs
wouldfitonapinhead!
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Origin (3): Bloomsserc.carleton.edu/images/ microbelife/topics/red_tide_genera.v3.jpg
Today, mo st pl ankton can be
found where deep ocean
currents rise to the surface
This upwelli ng water is rich in
nutrients and causes the
plankton to bloom
Blooms of certain plankton
called dinoflagellatesmay
give the water a red tinge
MiriamG odfrey
Dinoflagellate bloom
Origin (4): On the sea bedupload.wikimedia.org/wikipedia/ en/0/04/Plankton.jpg
When the plankton dies it rains
down on sea bed to form an
organic mu sh
Sea bed
en.wikipedia.org/wiki/Image:Nerr0328.jpg
If there are any animals on the
sea bed these will feed on the
organic particles
Origin (5): Black Shaleupload.wikimedia.org/wikipedia/ en/0/04/Plankton.jpg
However, i f there is li ttle or no
oxygen in the water then animals
cant survive and the organic
mush accumulates
Where sediment contains
more than 5% organic matter,
it eventually forms a rock
known as aBlack Shale
Earth Science W orld Image Bank
Origin (6): Cooking
www.oilandgasgeology.com/oil_gas_window.jpg
As Black Shale is buried, it is h eated.
Kerogen
Gas
Oil
Organic matter is first changed by the
increase in temperature into kerogen,
which is a solidform of hydrocarbon
Around 90C, it is changed into a liquid
state, which we call oil
Around 150C, it is changed into a gas
A rock that has produced oil and gas in
this way is known as a Source Rock
Origin (7): Migration
www.diveco.co.nz/ img/gallery/2006/diver_bubbles.jpg Hot oil and gas is less dense than
the source rock in which it occurs
Oil and gas migrate upwards up
through the rock in much the same
way that the air bubbles of an
underwater diver rise to the surface
The rising oil and gas eventually gets
trapped in pockets in the rock called
reservoirs
Rising oil
Origin (8): Ancient EarthRon Blakey, Arizona Flagstaff
During mid-Mesozoic times
around 150 million years ago,
conditions were just right
to build up huge thicknesses
of Black Shale source rocks
Ancient Earth
The worlds main oil deposits all formed in warm shallow seas
where plankton bloomed but bottom waters were deoxygenated
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Why is there oil in Texas? II. A Strategic Natural Resource
National Geographic, 2002
Origin (9): Source of North Sea Oil
Ancient Earth
Ian and Tonya West
The Kimmeridge Clay is a Black Shale with u p to 50% organic
matter. I t is th e main sou rce rock for the N orth Sea Oil & Gas
Province
Black Shale