Petroleum Geology Notes

What We Need for Success

  • A Rube Goldberg View of a Hydrocarbon System
  • Key components:
    • A “Kitchen” where organic material is cooked.
    • A “Container” from which oil & gas can be produced.
    • “Plumbing” to connect the container to the kitchen correctly.
    • Correctly placed wells.

The Container

  • Reservoir:
    • Porous & permeable rock suitable for production.
    • Most commonly sandstones & carbonates.
  • Trap:
    • 3-D configuration that “pools” the oil & gas.
    • Structural and/or Stratigraphic Traps.
  • Seal:
    • Rocks that prevent leakage from the trap.
    • Most commonly shales and evaporites.
    • Top Seals & Lateral Seals.

The Plumbing

  • Migration:
    • From source (shales) to porous reservoirs.
    • Strata-Parallel Component (sand & silt layers).
    • Cross-Strata Component (faults and/or fractures).

Introduction to Geology

  • Geology is the science that pursues an understanding of planet Earth.
  • Physical geology:
    • Examines the materials (Rocks, metals, soil) composing Earth.
    • Seeks to understand the many processes that operate beneath and upon its surface.
  • Historical geology:
    • Seeks an understanding of the origin of Earth and its development through time (Historical change, weather etc.).
    • Examples of geological processes: Earthquakes, Volcanism, Floods.

History of Petroleum Exploration and Petroleum Geology - From Nouh to OPEC

  • Geology is the science that pursues an Understanding of planet Earth.
  • Petros:
    • Derived from the Greek word “petros” for rock.
    • The Roman word petroleum for oil.
  • Oil was initially produced only from seepages.
  • Examples of geological processes: Floods, Volcanism, Earthquakes.

Historical Perspectives

  • In Pennsylvania, Colonel Edwin Drake drilled 69 feet and struck oil in 1859.
  • Until the mid 19th century, oil was produced only from seepages.
  • Creekology: Oil was more often found by wells located on river bottoms than by those on the hills.
  • Simple anticlinal trap.

Evolution of Petroleum Exploration Concepts and Techniques

  • One major U.S. company’s exploration philosophy was to dig on old Indian graves.
  • Another oil finder used to wear an old hat, run around the field until his hat dropped off, and start drilling where it landed.
  • Until the mid 19th century, oil was produced only from seepages.
  • Naturally occurring seepages of oil and associated asphalt deposits can be seen 50 km northeast of Luanda antos and Campos Basins of Brazil.
  • Natural petroleum seep and deposits of bitumen, north of Baku, Azerbaijan.

Creekology

  • Most of the oil discovered through seepages.
  • One of the earliest exploration tools was “creekology.”
  • It gradually dawned on the early drillers that oil was more often found by wells located on river bottoms than by those on the hills.
  • Creekology: the ease of finding oil in the old days.

Advances in Geophysics in the 1970s

  • The 1970s saw major advances on two fronts: geophysics
  • 1920’s many exploration techniques were used for petroleum exploration
    • Seismic method
    • Gravity method
    • Magnetic method
  • Petroleum exploration followed by
    • Electric logging
    • Sonic logging
    • Radioactive logging
  • 2D Anticline about 15 km wide and 75 long From seismic
  • Some Energy is Reflected, Most Energy is Transmitted.
  • Offshore seismic surveys
  • Gamma log
  • Resistivity log

Petroleum Geology in a Continuum

  • Petroleum geology is part of a continuum of disciplines employed in the exploration and production of oil and gas
  • Geophysics now extends beyond the beginning of production.
  • Repeated seismic surveys can monitor the migration of fluid interfaces within fields during their productive lifetime (4D seismic).

Historical Development of Drilling Technology

  • Early cable-tool rig used in America the motive power was provided by one man and a spring pole.
  • No RPM
  • Offshore drilling technology developed

Seven Sisters

  • Demand increased during WW1 (1914-1918) . and by 1920 the oil industry was dominated by seven sisters:
  • European:
    • British Petroleum “BP” and Shell
    • Found their oil reserves abroad from their parent countries, principally in the Middle and Far East)
  • American:
    • Chevron, Exxon, Mobil, Texaco, Gulf
    • Began overseas ventures, mainly in Central and South America
  • In the 1930s, the Arabian American Oil Company (Aramco, now Saudi Aramco) evolved from a consortium of Socal, Texaco, Mobil, and Exxon

Partners of Major Overseas Oil Consortia

  • Partners of Some of the Major Overseas Oil Consortia
  • Consortia and Companies:
    • Iran: BP, Shell, Exxon, Mobil, Gulf, Texaco, C.F.P.
    • I.P.C., Iraq: BP, Shell, Exxon, Mobil, Gulf, Texaco, C.F.P.
    • Aramco, Saudi Arabia: Exxon, Mobil, Texaco, Socal
    • Kuwait Oil Co., Kuwait: BP, Shell, Gulf
    • Admar, Abu Dhabi: BP, Shell, Exxon, Mobil, C.F.P., Conoco, Amerada, Marathon
    • A.D. P.C., Abu Dhabi
    • Libya: BP, Shell, Exxon, Mobil, Texaco, Socal, Amerada, Marathon
    • Oasis
      *Note that partners and their percentage interest varied over the lifetime of the various consortia.

Organization of Petroleum Exporting Countries (OPEC)

  • After WW2, Economic bloom, more demand, Exploration
  • 1960s: Organization of Petroleum Exporting Countries (OPEC), was founded in Baghdad- consists of Iraq, Iran, Saudi Arabia, Kuwait and Venezuela.
  • Then expanded to include Algeria, Dubai, Ecuador, Gabon, Indonesia, Libya, Nigeria, Qatar and UAE.
  • The most influential state oil and gas companies based in countries outside (New Seven Sisters) the OPEC (control almost one-third of the world’s oil and gas production)
    • China National Petroleum Corporation (China)
    • Gazprom (Russia)
    • National Iranian Oil Company (Iran)
    • Petrobras (Brazil)
    • Petroleos de Venezuela S.A. (Venezuela)
    • Petronas (Malaysia)

Oil Price Drop 2020

  • US oil price below zero for first time in history
  • Russia's refusal to reduce oil production in order to keep prices for oil at moderate level

Impact of the Global Financial Crisis on Crude Oil Price Volatility

  • Daily Price of West Texas Intermediate (WTI) Crude Oil Market (1970-2015)

Geology in Petroleum Industry

  • 3D seismic surveys

Why Work in the Energy Industry?

  • Focus of the Petroleum Industry
  • What drives today’s oil companies?

Energy Resources

  • World:
    • Nuclear power: 6%6\%
    • Hydropower, geothermal, solar, wind: 7%7\%
    • Natural Gas: 23%23\%
    • Biomass: 11%11\%
    • Oil: 32%32\%
    • Coal: 21%21\%
  • United States:
    • Nuclear power: 8%8\%
    • Hydropower geothermal solar, wind: 4%4\%
    • Biomass: 4%4\%
    • Natural Gas: 23%23\%
    • Oil: 39%39\%
    • Coal: 22%22\%
  • What drives today’s oil companies !

Growing Demand for Energy

  • Worldwide demand for energy will increase steadily out to 2040 and beyond
  • Projected demand for oil and gas in 2040 is 45% more than it was back in 2014 (1½% per year)
  • Chart updated in 2014

Industry’s Challenge – Filling the Gap

  • New = Fields we don’t know exist
  • Static = HC we know about, but can not produce economically
  • Probable = Newly found HC that may be economic to produce – need more confirmation wells
  • There is a huge GAP between projected production from existing fields and what industry needs to produce through 2040

Meeting Energy Demands

  • We can fill the gap in three ways:

A Fully-Integrated Upstream

  • How to Get It Out
    • where, in detail, are the reserves?
    • what to build (facilities)?
    • will it be profitable?
  • Find Oil & Gas ‘Pools’
    • which regions and basins?
    • which blocks?
    • where on the block?
  • From the Ground, to the Refinery
    • how to manage the field?
    • how to deliver the ‘crude’?

Drill Wells - Recover Oil & Gas

  • Drilling wells is a key activity in the Upstream
  • Exploration:
    • Drills wells to discover new HC reserves
  • Development:
    • Drills wells to delineate a new field and determine how best to extract the HCs
  • Production:
    • Drills wells to drain the field with the goal of maximizing the produced HCs while minimizing the costs
  • Industry uses technology, primarily reflection seismology, to determine where to drill

A Field’s Life Cycle

  • Just as a person has a life cycle, from infant to old age, an oil or gas field has a life cycle
    • Identify an Opportunity
    • Capture the Opportunity
    • Make a Discovery
    • Delineate the Field
    • Install Facilities
    • Drain the Field
    • Abandon the Field
  • New Ventures, Exploration, Development, Production

ADNOC Evolution

  • 2016: Strengthening the Foundation
    • Adnoc transformation
    • Integrated 2030 strategy
    • Harnessing synergies
  • 2017 - 2018: Building Momentum
    • Group companies under one ADNOC brand
    • 3.5 MMbd capacity by end 2018
    • Largest integrated refinery complex in the world announced
    • Full slate of Onshore & Offshore Concessions awarded
    • ADNOC Distribution IPO
    • Adnoc Drilling & BHGE partnership
    • First-ever block bid round launched
  • 2019 - 2020: Accelerating Growth & Value Creation
    • 4 MMbd capacity by end 2020
    • Signed $4bn KKR, Blackrock pipeline infrastructure deal
    • $5bn ENI, OMV refining JV
    • UDR concession; ENI, OMV, Wintershall
    • 1st Unconventionals concession; Total
    • 1st exploration licencing round concessions awarded; Eni /PTTEP, OXY, INPEX, BPRL/ IOCL
    • 2nd block bid round launched: 5 exploration blocks

ADNOC 2030 Strategy

  • A More Profitable Upstream and a More Sustainable & Economic Gas Supply
    • More Profitable Upstream
    • More Sustainable and Economic Gas Supply
    • More Valuable Downstream
    • More Proactive & Adaptive Marketing
    • Safety and Sustainability
    • Technology, Innovation & Human Capital
    • Strategic Partnerships
    • Large Scale Investments
  • Gas Replenish our Reserves
  • Exploration Strategic Partners & Smart Investment Partnership Operational Efficiency & Costs Efficiency

ADNOC Exploration Licensing Blocks

  • 2018 – launch of Abu Dhabi’s first-ever competitive exploration bid round; blocks successfully awarded early 2019
  • 2019 – launch of Abu Dhabi’s second competitive exploration bid round; awards expected to start 2020
  • Key Enablers:
    • Partners bringing technology and capabilities
    • Effective de-risking through appraisals
    • Detailed subsurface data through ADNOC’s world’s largest combined onshore & offshore seismic survey

ADNOC Oil Production Capacity Increase

  • 2020 target of 4.0 MMbd oil production capacity on-track
  • Key Enablers for long-term capacity increase
    • Drilling efficiency & advancement
    • Integrated Drilling Services
    • Creating value from smarter and more marginal fields
    • Maximizing synergies (e.g. Upper and Lower Zakum)
    • Developing tight & challenging reservoirs
    • Harnessing artificial islands concept
    • Effective project management (including smart FEED and procurement strategies)
    • EOR to effectively manage our maturing fields to ensure sustainability and optimum recovery

News

  • World's fourth largest: Dubai-Abu Dhabi gas field discovery to boost UAE's economic growth
  • UAE moves closer to energy self-sufficiency at viable costs with the 'Jebel Ali Project'
  • UAE makes 80 trillion scf gas discovery in Abu Dhabi and Dubai
  • UAE's ADNOC to build world's largest petrochem site worth $45bn

Drill Wisely

  • Wells can be very expensive, some > 250250 million, a lot of money even for a major oil company
  • Well placement and well path can be critical to success
  • So ….. How can we determine where to drill and predict what we will find BEFORE we start drilling?
  • This leads to the need for geologists, geophysicists, and other specialists focused on giving us images of the subsurface and then interpreting those images in terms of geology and fluids (oil & gas)

Location of World Petroleum Deposits

  • Map showing regions of major known oil reserves:
    • North Slope
    • North Sea
    • North America (Texas, Gulf of Mexico)
    • South America
    • Europe
    • Africa
    • Persian Gulf
    • Asia
    • Australia

The Context of Petroleum Geology

  • Petroleum geology is the application of geology (the study of rocks) to the exploration for and production of oil and gas
  • Geology itself is based on chemistry, physics and biology
    • Chemistry: mineralogy, secondary precipitations, organic origins, maturations and maturation
    • Physics: physical concepts on geophysical explorations, logging, and reservoir characterization
    • Biology: stratigraphical zonation, paleoenvironments, ecology and biochemistry

ODSN Plate Tectonic Reconstruction Service

  • Online software for plate tectonic reconstruction
  • Calculate plate tectonic reconstructions of any age back to 150 My.

Petroleum Geology in Context

  • Petroleum geology lies within a continuum of disciplines, beginning with geophysics and ending with petroleum engineering, but overlapping both in time and subject matter.
  • Oil companies exist not only to find oil and gas but, like any business enterprise, to make money.
  • Thus, every step of the journey, from leasing to drilling, to production, and finally to enhanced recovery, is monitored by accountants and economists

Summary of Evolution of Petroleum Exploration

  • The role of petroleum Geologist has become more and more skilled and demanding
  • wandering, Old hat exploration, Creekology
  • Hunt 1869: The anticlinal theory of oil entrapment
  • Mid-1920s: Seismic refraction, Gravity and magnatic methods were applied
  • 1927: electric log runsin the wells at France, sonic and radioactive methods followed
  • 1920s: Aerial surveying began
  • 1970s: Advent of Computer resulted in quantum jumb in Geophysics and Geochemistry
  • 1980s: 3D seismic and inhanced of wireline logging

Conditions for a Commercial Oil Accumulation

  • For a commercial oil accumulation to occur, seven conditions must be fulfilled
    1. There must be an organic-rich source rock to generate the oil and/or gas.
    2. The source rock must have been heated sufficiently to yield its petroleum.
    3. There must be a reservoir to contain the expelled hydrocarbons. This reservoir must have porosity, to contain the oil and/or gas, and permeability, to permit fluid flow.
    4. The reservoir must be sealed by an impermeable cap rock to prevent the upward escape of petroleum to the earth’s surface.
    5. Source, reservoir, and seal must be arranged in such a way as to trap the petroleum.
    6. The timing of trap formation, petroleum generation, and accumulation must be in a favorable sequence.
    7. The accumulation must be preserved or protected from breaching, flushing, aerobic bacteria, thermal degradation, etc. until exploitation.

Geoscience in Exploration & Production

  • 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 – Integrates various data to give us quantitative models of the petroleum potential of an area
  • Structural Geology – Provides an understanding of how the subsurface has been deformed as it bears on HC potential
  • 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 HC recovery

Self-Study Video Resources

  • Introduction to Petroleum Geology / Career Overview
  • Overview of of Petroleum Geology

Structural Geology

  • Structural geology study of the deformation of the surface and subsurface of the Earth and other planetary bodies. This deformation reflects past changes in local and regional stress and strain, and can be used to reconstruct past crustal movements and dynamics.
  • Sedimentology explores the origin, transport, deposition and diagenetic alterations of the materials that compose sediments and sedimentary rocks.
  • Stratigraphy investigates how those types of rocks are accumulated and distributed in space and time.
  • Thrust fault identified from biostratigraphic analysis: repeated strata indicated by the reappearance of zones H4 and I.

Well Production Options

  • Producing from a thin reservoir through multiple wells – expensive option
  • Producing from a thin reservoir through a single well – economical option

Sedimentology

  • Cubic packing: 48% porosity
  • Rhombohedral packing: 26% porosity
  • Udden-Wentworth Scale
    • Boulders
    • Cobbles
    • Gravel
    • Sand
    • Silt
    • Clay

Petrography & Organic Geochemistry

  • Petrography: The systematic description of geological materials (rock and minerals) , their composition, and organization, in hand specimens and thin sections using microscopic
  • Organic geochemistry which includes the study of organic matter in sediments and its transformation into hydrocarbons, has become another vital part of petroleum geology.

Paleontology

  • Paleontology: the science of the former life of the Earth, as preserved in fossils
  • The simplified geologic time scale and its basic subdivisions. Many of the subdivisions are based on the Principle of Faunal Succession, which recognizes that the Earth’s biota has changed through time.
  • Trilobite Fossil Cambrian Age (542-488 Ma)

Liostratigraphic correlation

  • Well AC-2 and Well AC-1
  • Nannofossil abundance and diversity plot
  • Nannofossil abundance and diversity plot
  • Top R.rotaria(7.0Ma)R. rotaria (7.0 Ma)
  • Top Discoaster berggrenii (6.0Ma)(6.0 Ma)
  • Downhole increase in Discoaster berggrenii
  • Onset of floral decline