Fracture and Collapse pressure is used to find the minimum and maximum mudweoight. The calculation are using Kirch equations and optional failure criteria. Most common is Mohr Coulomb.

Pore pressure

(Eaton, Matrix and Quick Look methods) - using trend lines d-Exponent

User Defined Calculations

Make your own calculations, performed on any log (no more spreadsheets). Use up to 8 logs in one calculations.

The PFAS Cycle

The PFAS Cycle POST ANALYSIS: The first stage is to utilise the collected data to produce the Final Well Report and in post-analysis. Based on experience transfer from previous wells the prognosis for the next well in an area may be established.

PLANNING: Planning is based on geological prognosis, rock strength correlations, in-situ stresses, pore pressure, well geometry and mud chemistry. A prognosis for well integrity trends based on effective stresses and strengths can then be established.

FOLLOW-UP: During drilling, well integrity trends, including well path and formation tops, may be monitored by updating: Pore pressure, stresses, lithology and mud weight. Registration of events during drilling or other information for post analysis purpose will may also be included.

PFAS may in particular be advantageous when planning advanced drilling operations, like Slim Hole Drilling, Under-Balanced Drilling, drilling of HTHP wells, Horizontal wells, Multi-Branch wells and in Deep Water Drilling operations, where well integrity issues are critical.

Logs are imported from ASCII text files and LAS files. PFAS can handle up to 200 logs in one project.
Templates simplify repetitive Import of logs from similar files and to View/Print uniform reports.
Merging of logs, user defined cut-off, compressing / stretching. Use templates to merge a new log section to existing data while drilling.
Units. At any time, a unit can be changed to a convertible unit. For example, the pore pressure may be displayed in sg, g/cm3, ppg or psi/ft. Depths can be in meters or feet.
Synthetic logs (for planning of new wells) can be made by compressing or stretching logs (copy and paste).
Correlations involving logs can be performed by using both log value and depth. Logical expressions can be used to perform calculation in selected intervals only. The result of the calculation can be a new log, or it can be merged to an existing log (in a given interval). (See User Defined Calculations)
Edit logs visually or in text mode. Click and drag, copy and paste segments of one log to another.
Lithology: can be entered as text or visually edited fast and easy.
Litho- and Chronostratigraphy: Choose from standard nomenclature for the actual field.
Depth Data (non log information): A user defined system for reporting all kind of depth related comments or events. Can easily be modified to meet individual needs and specifications. (Define your own symbols and plot options)
Presentation: All logs and data can be viewed/printed in the depth reference preferred and up to 12 tracks with 8 curves in each track can be shown at once. Templates saves time and makes presentations fast and consistent.
Deviated Wells: Logs can be imported in Measured depth or TVD. Survey data can be entered and updated at any time.
Free Text: Place comments anywhere on a presentation.

The PFAS Power

Data management
PFAS handles all kind of depth related data (for example logs or incidents related to depths) and time based drilling data. Attach a survey, and the reports can be presented in TVD or MD or both.

The figure below shows the data used by PFAS in a well planning process in Norsk Hydro.
NOTE: This is not required data, but it shows the power of the application. (A lot of useful information can come from only a few data in PFAS). QA/QC is an integrated part of PFAS.

Multiple Wells, Cross-section:

Up to 15 wells can be viewed at once to make correlations between the wells.