Oil & Gas Training
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Prospect Evaluation, Risks, and Volumes

A decision to drill an exploration well with the objective to find a new oil or gas field must be based on a sound assessment of the prospect's risks and of the volumes: what is the chance that a well will find hydrocarbons, and how much could it be? Risk and volume assessments form the basis for decisions to drill a well or not, and as such form the link between subsurface evaluation and the business aspects of the petroleum industry. This course explains how risks and volumes can be assessed in a realistic manner, based on a sound understanding of the geological details of the prospect as well as of its regional geological setting and current play understanding.

At the end of the course the participants will have a good understanding of the essentials for realistic risk and volume assessments of exploration prospects. The course should allow participants to produce well-considered and realistic assessments for prospects they may be working on, and to understand and constructively challenge risk and volume assessments of colleagues and/or partners/competitors (e.g. in a data room).

  • Agenda
  • Topics
  • Audience
  • Prerequisites
  • Agenda

    Day 1

    Welcome and Introduction

    • Risks, Volumes and Uncertainty
    • The difference between risk and uncertainty
    • Prospects and Plays
    • Play maps and demonstration of how understanding of the regional geology, petroleum systems and hydrocarbon plays is an essential element in the assessment of risks & volumes for individual prospects, exercises on the use of play maps for risk assessment
    • Prospects and Portfolios
    • Prospect maturation workflow, risk profiles and ranking of prospects, risk mitigation, scenarios in prospect assessment: when to use them and when not

    Day 2

    Traps and Reservoirs

    • Traps
    • Risks and uncertainties associated with hydrocarbon traps
    • Traps in important hydrocarbon settings
    • Trap types in rifts
    • Reservoirs
    • Risks and uncertainties associated with reservoir rocks
    • Reservoirs in important hydrocarbon settings
    • Reservoirs in rifts, passive margins, deltas, carbonate provinces and deep-water settings, and their typical characteristics and risks

    Day 3

    Seals, Pressures and Charge

    • Seals and pressures
    • Mechanisms of seal failure
    • Seals and pressures in important hydrocarbon settings
    • Seals and pressures in rifts
    • Impact of source rock types and timing issues for charge assessment
    • Charge in important hydrocarbon settings
    • Source rocks and charge in rifts

    Day 4

    Risks and Volumes

    • Risk assessment
    • Practical exercise in small groups on prospect risk assessment
    • Risk assessment continued
    • Continuation of exercise
    • Volume assessment
    • Practical back-of-the-envelope volume calculation exercise
    • Volumes an portfolios
    • The impact of dependencies between prospects in a portfolio, risking and volume assessment of prospects with stacked reservoir-seal pairs, adding probabilistic prospect volumes statistically correct

    Day 5

    Bringing it all Together

    • Exploration economics
    • Basics of assessing the economic value of prospects
    • Exploration economics Continued
    • Geophysical evidence
    • The impact on prospect POS (probability of success) of direct hydrocarbon indicators (DHIs) and/or positive (or negative) evidence form controlled source electromagnetics (CSEM) – consistent with Bayes’ theorem, exercises
    • Local examples
    • An opportunity to discuss examples that participants bring in the context of what was learned during the course
  • Topics

    The course will demonstrate that realistic risk and volume assessment is not a "black box" operation, but needs geological understanding of the prospect, and the regional setting.

    Specific topics that will be discussed include:

    • The fundamentals of Risk and Volumes assessment; translating geological understanding into reasonable numbers and ranges.

    • The difference between risk and uncertainty.

    • Fundamentals of statistics; including explanation of distribution curves, understanding of expectation curves, do's and don'ts for adding risked volumes, and Bayes theorem.

    • Uncertainty of trap, reservoir, seal and charge, illustrated by examples.

    • Guidelines and exercises for estimating risks realistically and consistently.

    • Calculating volume ranges for prospects and for portfolios of prospects; how to add prospect volumes for a correct representation of prospect portfolios.

    • Incorporation of geophysical evidence (DHIs) in a realistic risk assessment.

  • Audience

    This course is designed in the first place for geoscientists working in exploration, for prospect portfolio analysts and for their direct supervisors. It is also a very instructive course for staff from disciplines working closely with exploration staff, such as reservoir engineers, petrophysicists and geophysicists

  • Prerequisites

    Knowledge of Basic Petroleum Geology as related to Exploration. Knowledge of Basic Petroleum Economics is helpful but not required

  • Prerequisites

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