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The Understand Energy Learning Hub is a cross-campus effort of the Precourt Institute for Energy.

Prospecting for Oil and Natural Gas

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Fast Facts About
Prospecting for Oil and Natural Gas

Prospecting is the very first stage of the oil and natural gas development process. It consists of Exploration, Permitting and Leasing.

Exploration encompasses the processes and methods involved in locating potential sites for oil and gas drilling and extraction. Numerous tools are used to identify and characterize “prospects” for oil and natural gas development. These tools range from basic geological and paleontological understanding of a reservoir to acoustic and magnetic seismography enhanced by 3D imaging. Other factors such as road access, topography, and prior drilling results (if any) are also considered. If available, data from already existing wells in the reservoir is analyzed, such as well logs, cross-section data, and Estimated Ultimate Recovery (EUR), which is an estimate of the expected recovery of oil or gas from a producing well. Finally, the location must be economically and regulatorily available.

Permitting and Leasing are closely intertwined and follow exploration. Prior to drilling in hydrocarbon fields that were identified through the exploration process, permits and leases must be secured from the entity that owns the land and its associated mineral rights. In the United States there are four types of land ownership which influence this process: Private, Federal, State, and Tribal. The Federal Government manages leases on the outer continental shelf of the United States for offshore activity as well. The United States is the only country in the world that allows private ownership of mineral rights. Outside the United States, permitting and leasing of mineral rights are generally a government-managed process.

A flow diagram of land ownership and mineral rights in the United States, showing four types of land ownership: Private, Federal, State, and Tribal. Oil and gas leases and drilling permits may be issued by different entities depending on where the hydrocarbon exploration is located.

Taken together, the processes of exploration, permitting and leasing may take years to decades to accomplish, depending on the location and nature of the prospecting activity.

See our Drilling, Completing, and Producing Oil and Natural Gas Wells page for information on the steps that follow prospecting. See our Oil and Natural Gas pages for information on processing, refining, and transporting oil and natural gas after they are produced.

Porosity vs Permeability

Porosity is the volume of pore space in a rock as a percentage of the total volume the rock occupies.

Permeability is the ease with which fluids or gases can move through the interconnected pores of rock.

Both porosity and permeability are important factors for a productive oil or gas well

Types of Oil and Gas


  • Conventional oil (naturally high permeability)
  • Unconventional oil (low permeability)
    • Heavy oil
    • Tight oil
    • Oil sands
    • Oil shale


  • Conventional gas (naturally high permeability)
  • Unconventional gas (low permeability)
    • Shale gas
    • Tight sands gas
    • Coalbed methane
  • Methane hydrates (not commercial)

Prospecting Tools

Fossil correlation and dating of different core samples

Measuring of seismic waves to understand and map the subsurface

Well Logs
Logs that show the density, porosity, temperature, resistivity, and pressure at different depths

Geologic mapping of potential sites and data analytics of current wells


  • Continuing high demand for oil and gas
  • Can reduce energy dependence on other countries
  • Can reduce transportation costs from importing oil and gas
  • Potential to find reservoirs that are more economic


  • Geologic tools can be expensive
  • Lack of certainty that new drilling permits will be given
  • Strict regulations for oil and gas
  • Land use restrictions

Climate Impact: Low

Low gradient
  • Emissions from exploratory wells

Environmental Impact: High

High gradient
  • Exploratory wells require the clearing of vegetation and land
  • Seismic techniques of exploration disturb ecosystems
  • Road construction to prospecting sites cuts through ecosystems
  • Improper disposal of saline water pumped from the ground damages soil and groundwater


Updated September 2023

Before You Watch Our Lecture on
Prospecting for Oil and Natural Gas

We assign videos and readings to our Stanford students as pre-work for each lecture to help contextualize the lecture content. We strongly encourage you to review the Essential videos and readings below before watching our lecture on Prospecting for Oil and Natural Gas. Include selections from the Optional and Useful list based on your interests and available time.


Optional and Useful

Our Lecture on
Prospecting for Oil and Natural Gas

This is our Stanford University Understand Energy course lecture on oil and natural gas prospecting. We strongly encourage you to watch the full lecture to understand this important topic within the context of the oil and natural gas energy systems. For a complete learning experience, we also encourage you to watch / read the Essential videos and readings we assign to our students before watching the lecture.

Jane Woodward

Presented by: Jane Woodward, Adjunct Professor, Civil and Environmental Engineering, Stanford University; Founder and Managing Partner, WovenEarth Ventures; Founding Partner, MAP Energy
Recorded on: October 2, 2023   Duration: 30 minutes

Table of Contents

(Clicking on a timestamp will take you to YouTube.)
00:00 Introduction 
03:34 Oil and Natural Gas Rocks 
06:31 Anatomy of Oil and/or Natural Gas Fields 
11:26 Methods to Identify Oil and Gas 
17:51 Land Rights and Regulation 
28:50 Wrap Up Summary

Lecture slides available upon request.

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Additional Resources About
Prospecting for Oil and Natural Gas

Government and International Organizations