Oil Well Series - Covenant...

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JMA Oil Well Series: The Exploration Task Noel Adullahi WSG-CNL Lekki

Transcript of Oil Well Series - Covenant...

JMA

Oil Well Series:

The Exploration Task

Noel AdullahiWSG-CNL Lekki

JMA

What is Petroleum?

• Petroleum: a natural yellow-to-black flammable liquid hydrocarbon found beneath the earth’s surface

• Hydrocarbon: an organic compound made up of carbon and hydrogen atoms

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“The Prize”

THE_PRIZE_DISC11_1.MP4

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Petrochemical Products

• Detergents - Cosmetics• Fertilizers - Weed Killers• Medicine - Antiseptics - Anesthetics• Plastics - Synthetic Fibers• Synthetic Rubber• Rust Preventatives• Liquid Petroleum Gas

American Petroleum Institute, 1999

More Than 3,000 Products

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The Goal - ‘Black Gold’

Light Texas CrudePalo Pinto Field

North Texas

Heavy Texas CrudeHumble Oil FieldSouthwest Texas

Petroleum Supplies our Energy Needs

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Petroleum Products

Gasoline - 19.5 gallons

A Barrel of Crude Oil Provides:

Fuel Oil - 9.2 gallons

Jet Fuel - 4.1 gallons

Asphalt - 2.3 gallons

Kerosene - 0.2 gallonsLubricants - 0.5 gallonsPetrochemicals,other products - 6.2 gallons

One Barrel =42 gallons

American Petroleum Institute, 1999

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024839-2

Projected World Energy SuppliesProjected World Energy Supplies

19001900 19201920 19401940 19601960 19801980 20002000 20202020 20402040 20602060 20802080 30003000

2020

4040

6060

8080

100100100 BILLION

BARRELS

BillionBarrels

of OilEquivalent

per Year(GBOE)

BillionBarrels

of OilEquivalent

per Year(GBOE) Natural

GasNatural

Gas

HydroelectricHydroelectric

Crude OilCrude Oil

Solar, WindGeothermal

Nuclear Electric

1993

CoalCoal

24929

Decreasing

Fossil FuelsN

ew Technologies

World Energy Demand

after Edwards,AAPG 8/97

Careers inOil & Gas

Remain Important

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Where are oil & gas prospects found?

• An area where thick sedimentary sequences are deposited –usually thicker than those found in surrounding areas (Sedimentary basins). • A thickness of at least 2500 m to 5000 m of sediment is needed to ensure that the • source rocks are mature to the oil generation threshold May form at the plate margins and within the continent

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How are basins formed?

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Largest Hydrocarbon Basinsby Ultimate Potential

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Global ExplorationGlobal Oil and Gas Fields

GasOil

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Basins in Nigeria

American Petroleum Institute, 1999

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Exploring for Oil and gas

American Petroleum Institute, 1999

We explore for:• Thick sedimentary rock sequences

• Requirements for petroleum formation or generation & accumulation

• Hydrocarbon generation threshold• Commerciality of the hydrocarbon

JMA American Petroleum Institute, 1999

• Surface techniques –aerial photography, optical satellite imagery, field visits etc

• Geophysical techniques –gravity, magnetic, seismic

• Exploratory drilling

Exploration Techniques

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Gravity survey

American Petroleum Institute, 1999

• Usually used to detect thick sedimentary sequences

• Measures variation in density of rocks • The parameter measured is acceleration due to

gravity (g) –using gravimeter• Areas with thick low density sedimentary rocks

appear as negative anomalies• Areas with dense basement rocks appear as

positive anomalies

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Magnetic survey

American Petroleum Institute, 1999

• Usually used to determine the thickness of sediments or depth to basement & locate

important structural features • Rocks with magnetic properties have some

effects on the intensity & direction of earth’s magnetic field

• Measures the intensity & direction of earth’s magnetic field to give the distribution of

magnetic anomalies over the area of interest

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Gravity & magnetic survey responses

American Petroleum Institute, 1999

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Seismic Imaging3D Marine Data Acquisition

Silicon Graphics

• Boundaries between different rocks often reflect seismic waves

• Geophysicists use these waves to build pictures of what the subsurface looks like.

• P-wave travel velocity within the subsurface is converted to depth information

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Anticlinal Theory

GasOil

Water

Petroleum Accumulates in Structural Closure

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Seismic Image of Anticline

1000

2000

3000

Milli

seco

nds

1 km

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120° F120° F

350° F350° FGenerationGeneration

MigrationMigration

Seal RockSeal Rock

ReservoirRockReservoirRock

OilOil

WaterWater

Gas CapGas Cap

EntrapmentEntrapmentAccumulation

Source Rock

Petroleum System and Processes

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Petroleum System Processes• Generation - Burial of source rock to temperature and

pressure regime sufficient to convert organic matter into hydrocarbon

• Migration - Movement of hydrocarbon out of the sourcerock toward and into a trap

• Accumulation - A volume of hydrocarbon migrating into a trap faster than the trap leaks resulting in an accumulation

• Preservation - Hydrocarbon remains in reservoir and is not altered by biodegradation or “water-washing”

• Timing - Trap forms before and during hydrocarbon migrating

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Offshore Onshore

Daily Rig Cost1998 $90,0001999 $40,000(Single year contract)

Ultra DeepDaily Rig Cost1998 $180,0001999 $180,000(Five year contract)

Cost of Drilling Rigs

Daily Rig Cost1998 $60,0001999 $30,000(Single year contract)

JMA

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The Petroleum Geologist - A Detective

• Predicts where oil and gas occurs by ‘remote sensing’

• Uses tools to gather data - gravity and magneticsrock distribution and propertiesgeophysical imagingcomputer processing

& visualization

• Uses concepts to develop models:Anticlinal theory and petroleum systems

• Makes economic analysis and recommends drilling

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• Geophysics– Provides an image of the

subsurface and data useful for predicting rock type and the occurrence of petroleum.

• Regional Geology– Provides an understanding of

which areas are productive, why they are productive, and where else we should look.

• Basin Modeling– Quantitative integrated

models of the petroleum system: source, reservoir, seal, hydrocarbon charge.

Industry Geoscience Careers: Exploration and Producing

• Structural Geology– Provides an understanding of the

process of deformation of the subsurface due to external forces.

• Stratigraphy– Provides an understanding of

processes creating sedimentary units.

• Geochemistry– Chemistry of petroleum and its

sources to characterize the type, history and origin of petroleum.

• Reservoir Characterization– Describes the flow characteristics and

attributes of subsurface reservoirs for enhanced exploitation.