dbMap/Web – Prospect Resources and Economics

Prospect resources, including oil, gas and gas-liquids, are automatically calculated from the resources associated with the targets within the prospect.  The prospect resources are visible on the Prospect Resources & Economics screen.

This screen also allows the user to edit economics information for the prospect and re-run the computation manually.

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1. Resource type	Changing the selected resource type changes the values displayed in the results table below.  “Risked” options show the “Success Case” scaled by the chance of success.  “Truncated” options show distributions containing only values that are above the specified economic cut-off.
2. Advanced options	The advanced options provide a breakdown of the different possible scenarios that constitute economic success for the Prospect.  Economic success could be due to oil, gas, or both.  For instance, the “Oil Only Economic” option displays the resource values only for cases where oil is economic and gas is not economic.
3. Display in BOE	Selecting this option will cause any resources that have a conversion factor to be shown in Million Barrels of Oil Equivalent units.
4. Retain realizations	If this option is selected, when a computation is run, the raw simulation data will be stored and made available to download once the computation is complete.  This can be a large amount of data, especially when a large number of iterations is specified.
5. Economics	This section allows minimum economic values to be specified for different resources.  See the dedicated economics section below for details.

Economics

The economics section shows the minimum economic values for each resource.  This section is only editable when the selected resource type is “Success Case – Truncated” or “Risked – Truncated”.

There are two separate economic cut-offs (Meps) for Oil and Total gas (combined associated and non-associated).

Since the Total Gas Meps is applied to the sum of the associated and non-associated gas, no truncated values are available for these individual resources, only for the Total Sales Gas.  Also, since there is no Meps for Gas Liquids, truncated values are not shown for these either.  Even though these resources do not contribute to economic success, they will of course still be present.  These values can be seen using the advanced options to show, for instance, how much incidental condensate is present in the cases where gas is economic.

A read-only version of this information is also visible on the “Economics” tab of the Prospect screen.

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1. Enabled flag	If a resource does not have economics enabled, then it will not contribute to the “Truncated” results. If it is enabled, then only values above the specified cut-off value will be included in “Truncated” results.
2. cut-off value (MEPS)	This is the value that the quantity of the respective resource must reach to be considered economically viable.  A value of 0 means that the resource is always economic if it is present.
3. Justification	Textual justification for the choice of cut-off value.

Economics in Other Rollups

Since economics information applies to Prospects, other rollup screens behave in slightly different ways.  Below is a summary of how the different screens treat economics:

Drilling opportunity (single or list)	No economics
Play, Prospect list, Play + Prospect list	The total is considered economically successful if any prospect in the rollup is economically successful.  This includes cases where the prospect is successful due to a target outside the play.
Portfolio, Portfolio + Play	No economics

Unconventional Prospects

Unconventional Prospects have an extra option to define the Meur/Well for the prospect.  An unconventional Prospect is a Prospect containing at least one target with an unconventional compute method.  The target must also meet the criteria to be included in the Prospect rollup.

Meur/Well functions in much the same way as Meps.  The total Eur/Well for all the targets in the Prospect is truncated at the specified Meur/Well.  This yields the Pmeur (the chance of the Eur/Well reaching the Meur/well) which is included in the calculation of the Prospect Pc.  Conventional Prospects have an implicit Pmeur of 1 and this cannot be changed by the user.

Resource Types

When adding target-level resources together to obtain a total value for a prospect, there are several different factors to consider:

• How much resource is expected to be present?

• Assuming that the prospect is geologically successful, how much is expected?

• What is the chance of geological success?

• Assuming that the prospect is economically successful, how much is expected?

• What is the chance of economic success?

Here, geological success for a prospect is defined as at least one target in the prospect being geologically successful.  Geological success is governed by risk factors and dependencies.

Economic success for a prospect is defined as the sum of all eligible target values for a particular resource reaching the Meps value specified for the resource.

To capture this information, four different types of resource are shown: Success Case – Untruncated, Success Case Truncated, Risked – Untruncated and Risked – Truncated. The following table gives a brief description of the meaning of these different types:

Resource Type	Description
Success Case – Untruncated	The sum of all target values, excluding cases where all targets fail geologically
Success Case – Truncated	The sum of all target values, excluding cases where all targets fail geologically or the prospect fails economically
Risked – Untruncated	Success Case – Untruncated multiplied by the chance of success
Risked – Truncated	Success Case – Truncated multiplied by the chance of success and by the chance of reaching Meps

Advanced options:

Resource Type	Description
Oil Only Economic	Resource values for the cases where oil is economically successful (above Meps) and gas is not economically successful (below Meps).
Gas Only Economic	Resource values for the cases where gas is economically successful (above Meps) and oil is not economically successful (below Meps).
Both Economic	Resource values for the cases where both oil and gas are economically successful (above Meps).
Oil Only Economic – Risked	Oil Only Economic multiplied by the chance of success
Gas Only Economic – Risked	Gas Only Economic multiplied by the chance of success
Both Economic – Risked	Both Economic multiplied by the chance of success

Also shown are several probabilities:

Probability	Description
Pg	The chance of at least one target in the prospect being geologically successful.  That is, the chance of the Success Case distribution
Pmeps	The chance of the prospect being economically successful, assuming that it is geologically successful.  That is, the chance of the Success Case reaching Meps.
Pc	The chance of the prospect being geologically and economically successful.  This is the most important value as it describes the overall chance of a prospect being commercially successful.
Pmeur	Only applies to unconventional prospects.  This is the chance of the Eur reaching Meur and is analagous to Pmeps.  The Pc value also includes the Pmeur.
COS	The chance of a particular scenario occuring.  For instance, in the Oil Only Economic section, the COS is the chance of oil being economically successful and gas not being economically successful.

In order to understand the role of each of the different resource types, it is helpful to consider a simple example of a prospect with 2 targets A and B. There are 4 possible outcomes for these targets:

• Both fail

• A fails, B succeeds

• A succeeds, B fails

• Both succeed

As described above, the chance of success (Pg) of a prospect is defined as the chance of at least one target in the prospect being successful, so outcomes 2, 3, and 4 are all considered “successes” for the prospect as a whole.

The Success Case takes all of these “successful” outcomes into account, using risk factors and dependencies to determine the chances of success and failure for each target and hence the likelihood of each of the possible outcomes above.  The Success Case can be thought of as an average of all the possible success outcomes, each weighted according to the likelihood of the outcome occurring.

Since the Success Case – Untruncated includes only the successful outcomes, the chance of success (Pg) for the prospect must also be considered.  The Risked – Untruncated performs this function as it multiplies the success case by the chance of success.  This can be thought of as being normalised, and thus is better suited to comparisons between prospects.

The Success Case – Truncated and Risked – Truncated resources are similar to their untruncated counterparts, but include economics information.  The Success Case – Truncated distribution takes the Success Case – Untruncated distribution and limits it further by excluding any cases where the total is below Meps.  The result is the estimated total for the prospect assuming that it is geologically and economically successful.  Again, this value is not a complete picture, as there is obviously a risk of the prospect being a geological or economic failure.  So the Risked – Truncated resource combines the Success Case – Truncated result with the overall chance of success (Pc) to obtain the overall expected total for the prospect, which can be compared with other prospects.

Since economic success for the Prospect as a whole occurs when either oil or gas is economically successful, there are 3 different possible scenarios that lead to economic success:

The advanced options allow resource values to be viewed for each of these scenarios, as well as the likelihood of each scenario occurring.

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