Basin Analysis


Trainer(s): Jan de Jager
Duration: 10 sessions of 3 hour each

Business context

Objectives

  1. To provide participants with a sound understanding how, and under which conditions different basin types develop, and what the impact of their development is on the typical petroleum systems of these different basin types.
  2. To teach evaluation techniques that assist in the regional understanding and illustration of sedimentary basins and their development. Focus is on evaluation techniques that are often best done 'by hand'

This course will focus on geological fundamentals: how different basin types differ in subsidence mechanisms, basin cycles, heat flow through time, depositional systems, structural styles and their type of petroleum systems. This will allow participants to make realistic interpretations in new areas; interpretations that are consistent with the specific basin type and the to be expected depositional systems and structural styles.

In addition, through simple paper-based exercises, the course will provide background and understanding of how some of the typical PBE products are made: creaming curves, Field-size plots and Yet-to-find. Finally, the essentials of commercial assessments will be covered

Who should attend

This course is designed primarily for Geoscientists who have been working for several years in exploration and who want to improve their expertise of the prospect maturation process and risk and volume assessment, as well as for their direct supervisors.

It will also benefit staff from disciplines working closely with exploration staff including Prospect Portfolio Analysts, Petrophysicists, Geophysicists and Reservoir Engineers.

Learning, methods and tools

The course will be delivered online, in10 sessions of 3 hour each, with 2 breaks of 10 minutes per day. It is the intention to have at least 2 smaller exercises per day, plus a larger exercise as 'home assignment'; to be worked on after the online sessions and before the start of the next session. Time will be reserved for recapitulation, questions and discussions.

The platform for the online course is Zoom: presenting material can easily be done on this platform; people can raise their hand if they want to ask a question; the presenter can switch to a screen where he/she can see all participants (also when each is sitting in another location, such as at home); participants can ask questions by writing notes, but they can also be given the microphone; there is a whiteboard functionality that can be used as one would use a flip chart.

Exercises are focussed on illustrating basin framework and basin development in meaningful, often hand-made, sketches/illustrations. It is the intention to demonstrate that making such illustrations is helpful for developing one's own understanding as well as for effectively communicating concepts. Participants are encouraged to do exercises that would normally be done as 'paper exercises' on their tablets, which would allow them to send their work to the instructor - doing it on paper and taking a photo will also be fine.

For home-work assignments it is proposed to let each participant choose a basin (preferably the one he/she is working on) and have him/her making in different assignments specific diagrams for that basin (regional geological cross sections, chronostratigraphic chart, charge map, etc). The results must be sent to me (as course director), and I will comment back by email to each individual separately. General findings and examples of good illustrations that have been made will be presented to the group.

Day by day programme

Day 1 - Introduction to Basin Analysis

0.     Introduction and the basics:A brief introduction to what the course will cover and of the different basin types that will be discussed
1.     The Petroleum Industry:Setting the scene for the business environment in which basin studies are executed: Oil price changes over time; difference oil and gas
2.     Basin formation:How basins form; their plate tectonic settings; subsidence mechanisms, typical heat flow histories for different basin types.

Quiz on recognizing basin types and implications for heatflow history

3.     Basin cycles:Basin development can best be understood as consisting of several basin cycles, such as pre-rift, syn-rift, post-rift, inversion cycles. Pre-kinematic and syn-kinematic cycles in non-rifted basins.

Quiz on recognizing basin cycles

Presenting homework exercise

Day 2 - Controls on Sedimentation

0.     Recapitulation of previous day:brief summary of main learnings, providing an opportunity for questions; discussion of homework exercise
1.     Sea-level variations and subsidence:Introduction into the basics of sequence stratigraphy; what is a sequence; how do they form

Exercise on sequence stratigraphy

2.     Climate and ocean-currents:Influence of climate and ocean currents on depositional systems; arid versus humid climates; hot versus cold climates; link of upwelling zones to paleogeographic position of basin settings; global oceanic anoxic events; examples of Atlantic and GOM marine source rocks

Quiz on source rocks based on paleogeographic and plate setting

3.     Tectonics:Sediment dispersal in syn-tectonic settings, such as rift basins, foredeeps, deltas, deep-water foldbelts.

Presenting homework exercise
Day 3 - Non-Clastics and Source Rocks

0.     Recapitulation of previous day:brief summary of main learnings, providing an opportunity for questions; discussion of homework exercise
1.     Source Rock development in different basin types: Differences between source rock types; how source rock deposition and types are linked to depositional setting and basin cycles

Exercise on identifying potential source rocks from seismic

2.     Salt basins:Examples of different types of salt basins and their typical structural stiles: intra-cratonic (e.g. Southern Permian Basin); passive margin (e.g. South Atlantic); orogenic settings (e.g. Zagros Mnts, Jura Mnts, Pyrenees); Gulf of Mexico.

Exercise on identifying different stages of salt dome development.

3.     Carbonate settings:Conditions under which carbonates develop: build-ups at continental break in mixed settings; platform carbonates in shallow epicontinental seas; large reef complexes on subsiding shelfs or on oceanic crust.

Presenting homework exercise
 
Day 4 - The art of regional seismic interpretation

0.     Recapitulation of previous day:brief summary of main learnings, providing an opportunity for questions; discussion of homework exercise
1.     Regional seismic interpretation:The difference with workstation interpretation of 3D data sets and regional basin-wide interpretations

Exercise on seismic interpretation of regional structural setting

2.     Regional structural evaluation:How to undertake regional structural interpretation

Exercise on seismic interpretation of regional structural setting (different basin type)

Presenting homework exercise

Day 5 - The art of regional sequence interpretation

0.     Recapitulation of previous day:brief summary of main learnings, providing an opportunity for questions; discussion of homework exercise
1.     Seismo-stratigraphy:Application of sequence-stratigraphic concepts to seismic interpretation

Exercise seismo-stratigraphic interpretation

2.     Chronostratigraphic charts:How to construct meaningful basin-wide chronostratigraphic charts based on seismic and well data

Exercise making a chrono-stratigraphic chart

Presenting homework exercise

Day 6 - Failed Rift Basins

0.     Recapitulation of previous day:brief summary of main learnings, providing an opportunity for questions; discussion of homework exercise
1.     Syn-rift basin-cycle:Typical development and characteristics; illustrating differences and similarities with examples from SE Asia, North Sea, Sirte Basin, Gippsland Basin, Malay Basin

Exercise on identifying rift basin cycles from seismic

2.     Post-rift basin-cycle and inversions:Typical development and characteristics; illustrating differences and similarities with examples from Southern North Sea, SE Asia, West Siberian Basin, Gippsland Basin, Malay Basin

Exercise on identifying timing of inversion from seismic

3.     Petroleum systems in Failed Rift Basins:Typical source rocks, reservoirs, seals and traps per basin cycle. Examples of fields and trap types

Presenting homework exercise

Day 7 - Successful Rift Basins / Passive Margins

0.     Recapitulation of previous day:brief summary of main learnings, providing an opportunity for questions; discussion of homework exercise
1.     Passive Margin development:Typical development of passive margins, similarities and differences illustrated with examples from the South Atlantic, Norway, Australia

Exercise on identifying basin cycles from seismic

2.     Oblique slip margins:Typical development and structural style; petroleum systems and trap types
3.     Guyana-Surinam Basin:Case-history of identifying main basin elements from plate-tectonic setting

Exercise on Guyana-Surinam Basin

Presenting homework exercise

Day 8 - Deltas and Deep-Water Settings

0.     Recapitulation of previous day:brief summary of main learnings, providing an opportunity for questions; discussion of homework exercise
1.     Deltas:Typical delta development; where to expect reservoirs and seals; typical traps; clay smear

Exercise on contouring in a typical delta setting

2.     Deep-water foldbelts:Basin cycles in deep-water foldbelts; pre-kinematic versus syn-kinematic, and implications for prospectivety

Exercise (seismic line) on identifying pre- and syn-kinematic sequences and timing of structuration in a deep-water foldbelt

Presenting homework exercise

Day 9 - Basin and Play statistics

0.     Recapitulation of previous day:brief summary of main learnings, providing an opportunity for questions; discussion of homework exercise
1.     Creaming Curves:How they are made; what they show; some typical examples

Exercise on making a creaming curve by hand

2.     Field-size plots:How field-size plots are made; what they show; how field-size distributions change with increasing play maturity

Exercise on constructing an FSD plot by hand

3.     Analogues and Base rates:What are good (and what are poor) analogues; using base rates for constraining predictions; the value of dry well analysis and look-back studies

Presenting homework exercise

Day 10 - Yet-to-find and Economics

0.     Recapitulation of previous day:brief summary of main learnings, providing an opportunity for questions; discussion of homework exercise
1.     Yet-to-find:Presentation of different methods to assess YTF of a basin or play; pitfalls and issues

Exercise on assessing YTF

2.     Exploration Economics: Introduction to how the commercial value of exploration ventures and prospects is assessed; explanation of terms like MSV and NPVfc and difference with forward looking NPVdev

Exercise on calculation of EMV

3.     Course close out