OIL & GAS IN TEXAS

  • Potential Question: Which Middle East countries produce more oil than Texas?

Geological Context

  • Locations related to oil and gas production:
    • Strawn/Tannehill
    • Clearfork
    • Horseshoe Alall
    • Caddo/Tannehill Canyon
    • Smackover
    • Petit
    • Spraberry Dean
    • Upper Barnett, Taylor

Production Statistics (2019)

  • Texas Oil Production: 5.4 million barrels (MM Bbls) of oil per day.
  • Texas Natural Gas Production: 35 billion cubic feet per day (Bcf/d).

Active Oil and Gas Wells

  • Total active oil wells: 187,400
  • Total active gas wells: 98,700

Texas Oil & Gas Reserves

  • Oil reserves: 46 billion Bbls
  • Natural gas reserves: 280 trillion cubic feet (TCF)
  • Liquid reserves: 20 billion Bbls

Rock Types and Geological Formations

  • Madrock type: Mixed rock type
  • Common geological formations include:
    • Austin Chalk
    • Eagle Ford
    • Cambrian
    • Olmos
    • San Miguel
    • Carbonate
    • Sandstone
    • Wilcox

U.S. Crude Oil Production (2010-2019)

  • Bar chart illustrating production in million barrels per day with annual changes shown for the years 2018-2019 across various states, including Texas, New Mexico, North Dakota, Oklahoma, Colorado, and offshore Gulf of Mexico.

Monthly U.S. Natural Gas Withdrawals (2006-2019)

  • Chart outlining natural gas gross withdrawals in billion cubic feet per day, showcasing trends and annual changes from 2006 to 2019.

ENGINEERING ETHICS

Key Distinctions

  • Morality vs. Professional Ethics:
    • Morality: Applies to everyone universally.
    • Engineering Ethics: Specifically applies to engineers and encompasses the teaching of engineering disciplines.

Importance of Teaching Engineering Ethics

  • Engineers have been significant players in historical tragedies and disasters, highlighting the need for ethical guidelines. Examples include:
    • Chernobyl accident (April 25-26, 1986)
    • Bhopal tragedy (December 2-3, 1984)
    • Tacoma Narrows Bridge (November 7, 1940)
    • Charles De Gaulle Airport incident (May 3, 2004)
    • Deepwater Horizon oil spill (April 20, 2010)

Methods of Teaching Ethics

  • Case studies are utilized to illustrate ethical dilemmas and lessons in engineering practices.

SEDIMENTATION

Sediment Types and Sizes

  • Classification of sediment based on size:
    • Very Coarse Sand: 1-2 mm
    • Coarse Sand: 0.5-1 mm
    • Medium Sand: 0.25-0.50 mm
    • Fine Sand: 0.125-0.25 mm
    • Very Fine Sand: 0.05-0.125 mm
    • Coarse Silt: 0.01-0.05 mm
    • Fine Silt: 0.005-0.01 mm
    • Clay: <0.005 mm

Sedimentation Rate

  • Average sedimentation occurs at a rate of approximately 1 cm per 1000 years.

Depositional Environments

  • Common environments where sedimentation occurs:
    • Rivers
    • Deltas
    • Beaches and Barrier Islands
    • Deep Water

POST DEPOSITIONAL FACTORS

Factors Affecting Sedimentary Rocks

  • Cementation: The process wherein mineral growth binds sediment grains together.
  • Compaction: Reduction in pore space and volume due to overburden pressure.
  • Solution: Dissolution of minerals, affecting pore fluid chemistry.
  • Fracturing: Development of fractures that can affect fluid movement and storage.
  • Diagenetic Alterations: Changes occurring in sediment post-deposition due to changes in temperature, pressure, and chemistry.

DESCRIPTION OF SEDIMENTARY ROCKS

Rock Texture

  • Major characteristics of sedimentary rocks include:
    • Size: Granule dimension classification.
    • Shape: Sphericity and roundness considerations.
    • Sorting: Distribution of grain sizes across samples.
    • Arrangement: Orientation and spatial organization of sediment grains.

Sorting Categories

  • Well-Sorted: Uniformity in grain size.
  • Poorly Sorted: Variation in grain sizes within the sediment sample.

RESERVOIR FLUID SYSTEMS - BLACK OIL

Fluid Characteristics

  • Mechanics of Black Oil in reservoirs include:
    • Bubble-point line: Determines phase behavior of oil under varying pressure.
    • Dew-point line: Trigger for gas release under decreasing pressure.

Oil Recovery and Fluid Behavior

  • Gas-Oil Ratios (GOR) of generally 2000 scf/bbl or less are noted, with increasing GOR during production as the reservoir pressure declines.
  • Stock tank oil gravity usually remains below 45 API, decreasing slightly over time due to loss of light hydrocarbons.
  • Oil formation volume factor generally remains below 2 res bbl/STB.
  • Fluid states transition from undersaturated to saturated, where sufficient gas can now occupy the fluid phase.
  • The production modeling of Black Oil remains complex due to the intricate behavior of fluid dynamics.

PAPAY'S EQUATION

Equation Formulation

  • The equation for calculating Z-factor:
    • (Z=1+0.274PRI100.8157TR+3.52PR100.9813TR)(Z = 1 + \frac{0.274 PRI}{100.8157TR} + \frac{3.52 PR}{100.9813TR})

FLUID SATURATION

Definitions

  • Fluid saturation is defined as the fraction of pore volume occupied by a specific fluid:
    • General formula: saturation=V<em>specific fluidV</em>pore spacesaturation = \frac{V<em>{specific\ fluid}}{V</em>{pore\ space}}
    • Sw: Water saturation
    • So: Oil saturation
    • Sg: Gas saturation
    • Sh: Hydrocarbon saturation = So + Sg

Hydrocarbon Accumulation Concepts

  • Hydrocarbon accumulation basics include:
    • Initially, pore space is filled 100% with water.
    • Hydrocarbons migrate up dip into traps guided by capillary forces and gravity.
    • Remaining connate water saturation persists within the hydrocarbon zone, indicating areas of fluid retention in the formation.