Mod 1

• Petroleum geology addresses the origin, distribution, exploration, development, and production of oil and natural gas resources
• Main focuses of petroleum geology:

  • Source rocks
  • Traps
  • Seals
  • Reservoirs
• In the 19th and early 20th centuries, oil exploration was based on surface mapping of anticlines
• Stratigraphic traps in petroleum exploration are caused by variations in deposition, erosion, or diagenesis within the reservoir
• One of the main applications to oil exploration was the development of micropaleontology, providing new insights into ancient sedimentary facies and their interpretation
• For a commercial oil accumulation to occur, five conditions must be fulfilled:

  1. Organic-rich source rock

  2. Source rock heated sufficiently

  3. Reservoir with porosity and permeability

  4. Reservoir sealed by an impermeable cap rock

  5. Source, reservoir, and seal arranged to trap the petroleum
• Most petroleum geologists believe that petroleum forms from the diagenesis of buried organic matter and is indigenous to sedimentary rocks rather than igneous rocks
• Petroleum geology applies geology to the exploration for and production of oil and gas, relying on chemistry, physics, and biology
• Geology, including petroleum geology, relies on value judgments based on experience and an assessment of validity among the data presented
• Geochemistry, a branch of chemistry applied to the study of rocks, is crucial in petroleum geology for understanding the mineralogical composition of rocks and predicting porosity changes during burial
• Physics plays a significant role in petroleum geology, especially in understanding folds, faults, and diapirs for petroleum entrapment, and modern petroleum exploration heavily relies on magnetic, gravity, and seismic surveys
• Biology, particularly through paleontology and ecology, is important in petroleum geology for establishing biostratigraphic zones and studying the relationship between living organisms and their environment
• Petroleum geology is just one aspect of petroleum exploration and production, which involves integrated teams with a wide range of professional skills, including political and social expertise, geophysical interpretation, and petroleum engineering