petroleum wells and wellbore classification in norway

Petroleum wells and wellbore classification in Norway Which challenges are we facing and which trade-offs must be done?

ECIM Haugesund - 2014

Kjell Reidar Knudsen

Content

• What does the term “well” means (in Norway)?

• Petroleum “Well-wellbore model”

• Naming of wells and wellbores in Norway

• Classification of Petroleum wellbores

• Challenges in well data representation

Kjell Reidar Knudsen, NPD, September 2014 2

Norway:

• NGU (Onshore geology and hydrology )

• Exploration boreholes (Norw. Sonderingsboring)

• Rock well (incl. geothermal)

• Unconsolidated wells

• LGN wells (Groundwater level monitoring)

• NPD (Petroleum)

• Well - Wellbores

Kjell Reidar Knudsen, NPD, September 2014

175 000 – 225 000 wells

(65 000 in GRANADA database)

5500 wellbores

(all in NPD database)

3

NGU and NVE database available on internet


Norwegian Petroleum «Well Model»


Well

Wellbore

Technical sidetrack

NPD

Databases Diskos

Database

Well ~ Wellbore ?

Unique starting point

Unique target point

Same target point

5

Relationship between well and wellbores


Norwegian Petroleum Statistics:

• www.npd.no


5452 wellbores ~ 3600 wells

7

http://www.npd.no/

Norwegian well and wellbore naming convention

• Unlike the situation for groundwater wells, the Petroleum regime has embedded lots of attributes (information) into the «name».

• Skilled staff can understand a lot by just looking at the well name

• Type of well (exploration or development)

• Location (in which block, i.e . south or far north etc.)

• Connections to production facilities

• Drilling sequence (first or later compared to others)

• Any discontinuity in the drilling process

• If the well is a sub sea completion

• The naming convention is still followed, even if all this information is kept as attributes in databases and can be sorted by and easily presented in reports and listings

• The creativity in technical solutions (well technology) makes it even more difficult to stick to a consistent naming convention

• But we try……………..

• See.. http://www.npd.no/Global/Norsk/5-Regelverk/Tematiske-veiledninger/Bronner_betegnelser_og_klassifisering_e.pdf


http://www.npd.no/Global/Norsk/5-Regelverk/Tematiske-veiledninger/Bronner_betegnelser_og_klassifisering_e.pdf






Well and wellbore names must have fixed character positions


Naming of multilateral wellbores


Multilateral wellbore: In contrast to sidetracked wells where the first bottom section is plugged back before a sidetrack is drilled, multilateral wellbores have more than one wellbore open at the same time. Wellbores planned as multilaterals are named Y1, Y2, Y3 etc. (Item V), i.e. 31/2-L-12 Y1H and 31/2-L-12 Y2H If a wellbore originally was not planned as multilateral, and the decision to drill multilateral from this wellbore is made at a later stage, the original wellbore keeps it’s name, i.e. 6608/10-E-1 H and the new wellbores are named Y2, Y3 etc. i.e. 6608/10-E-1 Y2H. (But also the first one get an attribute in the NPD database saying it is a multilateral one, even if it is not in the name). The numbering of the wellbores does not necessarily reflect the order the wellbores were drilled in.

10

Example of «Multilateral wellbores»


Another «Trade-off» Re-entry

• Useful for two purposes

• A new rig comes in, with new set of well attributes ( ex RKB, Rig name etc.)

• Database software calculate the «number of drilling days»

• Re-entries make new NPDID_Wellbores,

• but is not counted as separate wellbores in the NPD statistics


Classification of wellbores

• Attributes for classification

• "Type"

• "Purpose"

• Other vital wellbore attributes that can be used for classification

• Status (Present wellbore status)

• Other wellbore attributes that can be used for classifications or grouping (part of name)

• Deviated or not (code= S if exploration wellbores are deviated)

• Wellbore being a sidetrack or not

• If there are “Re-entries” done in the wellbores

• If the wellbores are part of a “multilateral wellbore” or not

• If the wellbore has a “Sub-sea”-wellhead (H as part of the name)



• Exploration

• Wildcat

• Appraisal

• Development

• Production

• Injection

• Observation

• Co2

• Other

• Soil Drilling

• Shallow gas

• Pilot

• Scientific

• Stratigraphic


Wellbore types

Wellbore purpose

14


• Exploration

• Development

• Co2

• Other • Soil Drilling

• Shallow gas

• Pilot

• Scientific

• Stratigraphic


According to Exploration license

(P-Act Section 2-1) or Production

License

According to Production License

P-Act Section 3-3

According to the regulation :

«Forskrift om transport av CO2 og

utnyttelse av undersjøiske

reservoarer på kontinentalsokkelen til

lagring av CO2 (under utarbeidelse)

According to Act of Scientific

research

According to Production License

P-Act Section 3-3

15

Challenges

• Changes that happens over the wellbore’s lifetime

• Wellbore type

• Wellbore purpose

• Wellbore status

• Other attributes

• Stick to old conventions when technology changes

• Drilling technology

• Multilateral wellbores, deviated /horizontal wells, advanced completions etc.

• IT

• Database technology (volume restrictions, free text search, fixed positions

• Web services, WebMapservices, Semantic web etc.

• National and international cooperation,

• Sharing data through common solutions/maps

• Standardization efforts: Inspire, Eurogeosource, PPDM, Energistics etc.


Reclassification of «types» of wellbores :

• From Exploration wellbores to Development wellbores

• The exploration wellbore does not disappear from the listings

• If they start producing/injecting from an exploration wellbore, a additional development wellbore will be entered in the database in addition to the exploration wellbore, and the exploration well gets an attribute that shows what has happened (both are counted in the statistics)

• From Development wellbores to Exploration wellbores

• This is not done any longer (was done many years ago)

• If new discoveries are made in a development wellbore, the development well will then get the attribute «development wellbore with discovery»

• In the past, development wellbores were re-classified to exploration wellbores, if a discovery was made, based on the convention that discoveries could only be made in exploration wellbores.


Reclassifications of wellbore «purpose»

• NPD does reclassify wellbore purpose from «wildcat» to «appraisal» for exploration wellbores by just modifying the “purpose” attribute

• the “original planned purpose” attribute is kept

• NPD does not keep updates of development wellbores «purpose»

• as this is dynamic information which is not easily available to the NPD


Conclusion

• Be thankful that if you don’t have old databases and a lot of data stored…

• You can start from scratch and make an intelligent, streamlined solutions

• Take advantage of all “previous” experience of others

• Build flexibility into your database solution (especially for changes over time)

• Don’t put too much logic into each parameter

• If you have a legacy database

• Consider establishing a data warehouse where terminology and definitions are as consistent as possible with the relevant legal documents (Acts and Regulations)

• Or plan for migration of all old data to a new database

• But

• Never change the names of old wells (may mean you have to keep the old well – wellbore model)

• Use the National Naming System for new wells if this exist (as in Norway)

• You may be left with inelegant ways of handling of dynamic attributes (instead of/in addition to history-tracking them (from-to- dates))


• Thank you for listening


petroleum wells and wellbore classification in norway

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