History of exploration
Academic seismic and drilling (1950 - 1974)
- 1950s - seismic refraction profiles shot across the Falklands area by the Lamont-Doherty Geological Observatory.
- 1970s - a range of mostly academic studies, culminating in the three DSDP boreholes on the Maurice Ewing Bank; these boreholes proved the existence of potential oil source rocks in the area.
Speculative seismic data (1977 - 2001)
- 1977-78 - two speculative, regional seismic surveys shot by Western Geophysical and GSI - some 21,652 km of data.
- 1993 and 1994 - Geco-Prakla and Spectrum acquired regional reconnaissance speculative seismic data both south and north of the Islands respectively, with a combined total of 15,558 km.
- 1995 - Spectrum acquired infill speculative seismic data over their original reconnaissance grid to the north of the Islands; this infill survey comprises 3,650 km of data with a five kilometre spacing between lines.
- 1997 - Spectrum acquired a grid of seismic data over the Special
Co-operation Area, infilling
the original regional reconnaissance grid laid down by Geco-Prakla.
These data were reprocessed by Spectrum in 2000, and provide excellent
quality data over the SCA region.
Note: the Special Co-operation Area agreement, established in 1996, has been rescinded by Argentina. Acreage on each side of the line designating the western edge of the Falkland Islands Designated Exploration Area that was formerly covered by the SCA agreement has therefore now reverted to the control of the relevant national jurisdiction. - 2001 - Lundin Oil acquired 1,250 km of seismic data over the unlicensed area immediately north of Tranches A and B in the North Falkland Basin in lieu of a well in Tranche F, but are available for purchase (from Talisman Energy) by companies interested in applying for licences in that area under the open-door licensing policy being pursued by the Government.
Argentine wells (1980 - 1994)
- Exxon, YPF and Oxy drilled 17 wells were drilled in Argentine waters of the Malvinas Basin
- The geology of these wells has been summarised by Galeazzi (1998).
- Five wells had encouraging shows of oil and gas in an under-charged Lower Cretaceous reservoir.
- The Calamar x-1 well flowed about 3,200 barrels of 37° API oil per day.
- A well drilled in late 1994 in the San Julian Basin to the northwest of the Islands is reported to have had oil shows within a 300 m thick reservoir interval.
Falklands Production Licences - North Falkland Basin
- 1996 - seven Production Licences were awarded (to 14 companies) in the North Falkland Basin as a result of a competitive bidding round. The licences covered 48 blocks (some 12,800 square kilometres).
-
1999 onwards – several phases of relinquishment and operator
changes to original licence areas in North Falkland Basin.
- November 2004 – two new licences covering 16 blocks in the southernmost part of the North Falkland Basin awarded to Rockhopper Exploration.
- April 2005 - two new licences covering 6 blocks in the northern part of the North Falkland Basin awarded to Rockhopper Exploration. These 6 blocks were previously licensed to Shell and Agip.
- August 2008 - a new licence covering 2.25 blocks in the southern part of the North Falkland Basin awarded to Desire Petroleum in association with Arcadia Petroleum.
- Current North Falkland Basin operators are Desire Petroleum, Argos Resources and Rockhopper Exploration. Rockhopper also partner Desire in two of their licences, and Arcadia partner Desire in parts of three of their licences.
Falkland Production Licences - Southern Basins
Open door licences -
status November 2004
Open door licences -
status December 2004
Open door licences -
status August 2008
- 2001 – ten Production Licences awarded covering 232 blocks over the southern area to the Falklands Hydrocarbon Consortium (Falkland Oil and Gas Ltd and Hardman Resources), with Falkland Oil and Gas Ltd (FOGL) as operator.
- 2003 – two licences and 37 blocks (90 blocks in total), relinquished by the Falklands Hydrocarbon Consortium (Falkland Oil and Gas Ltd and Hardman Resources) in the southern area as per licence conditions.
- 2004 – Five licences awarded covering 80 blocks over the southern area to Borders and Southern Petroleum Ltd.
- 2004 - A further seven licences, covering 195 blocks over 7 Quadrants in the Falkland Plateau Basin were awarded to Falkland Oil and Gas Ltd in December 2004. Unlike the other acreage held in the southern basins by FOGL, Hardman Resources do not partner them in these new licences.
- 2005 - FOGL/Hardman relinquished a further 18 blocks as per their licence agreement.
- July 2006 - FOGL relinquished 50% of their licence holding in their 2002 licences held in conjuction with Hardman Resources. This relinquishment was required by the Falkland Islands Government in exchange for changes to the agreed work programme.
- The Government proactively extended Phase 1 terms of "Open Door" licences, principally to accommodate drilling in Phase 1. Phase 2 was also extended in order to facilitate longer-term planning.
- September 2007 - FOGL were required by Government to relinquish PL030, followed by, in December 2007, 25% of the remainder of their 2004 licences. BHP Billiton farmed into all the FOGL acreage, and agreed to drill one well in the 2002 licences during Phase 1, one well in the 2004 licences during Phase 1, and one well in each set of licences during phase 2 if they opt to enter Phase 2.
The Falklands Offshore Sharing Agreement (FOSA)
- FOSA was established before drilling in the North Falkland Basin, and disbanded in 1999.
- FOSA comprised Shell, Amerada Hess, Lasmo and IPC and their respective partners.
- FOSA undertook all of the logistics and support work to facilitate a multi-well drilling campaign in the North Falkland Basin.
- FOSA was managed through a steering committee composed of each operating company.
-
Each company also took direct
responsibility for one or more aspects of the FOSA agreement:
- drilling services (managed by Amerada Hess);
- the operations base and supplies (managed by Lasmo);
- health and safety issues, aviation and site survey work (all managed by Shell);
- environmental work (managed by Lasmo);
- finance/tax (managed by Amerada and Lasmo).
- FOSA managed the sharing of a single rig, supply base, aviation link, site survey facility and operations/logging staff.
- FOSA resulted in savings of over £24m per company.
-
FOSA provided:
- a larger pool of expertise than could be provided in-house;
- greater flexibility than if each company were mounting a single or two well drilling operation;
- a reduced manpower requirement;
- a unified voice on many issues;
- companies with enhanced bargaining power when dealing with suppliers;
- a minimal operational/manpower impact on the community;
- a huge amount of knowledge in terms of environmental protection and associated monitoring.
A hard copy of the FOSA exploration close-out report can be downloaded here.
Wells drilled in the 1998 drilling campaign in North Falkland Basin
Well Status Table- Six wells were drilled in the North Falkland Basin during 1998.
- The six wells were drilled over an eight month period, using a shared rig on a back to back basis.
- Technical challenges of drilling in Falklands waters were proved to be far less severe than anticipated.
- Five of the six wells drilled had oil shows.
- Most wells found oil within post-rift sandstones located immediately above the main source rock interval, but this reservoir was under-charged as it lies above the main regional source-seal couplet.
- Live oil was recovered to surface from one of the Shell wells: the oil has an API gravity of 27°, and was from a thin sandstone at 3,000m.
- Significant levels of gas were recorded in one Shell well from a deep petroleum system.
- Sufficient was learnt about the basin and its petroleum systems to anticipate success in future operations.
-
Back to back drilling was the
one major disadvantage of the FOSA sharing agreement described above:
- operators were sharing a single rig, with rental rate near the peak of the market, and there was no time available for analysis of well results before the next well had to be spudded;
- the problem was compounded by the fact that the drill sites had been chosen at least six months in advance;
- there was no chance to pick completely new locations, with new play concepts, based on the results of the wells as they were drilled;
- consequently, only a small number of play types were actually tested, and extensive post-drilling analysis (conducted slowly and with the benefit of hindsight) has identified several other play concepts that might have been better options for drilling.
| Licence | Original Operator | Current Operator if different | 1st Phase minimum work prog | 2nd Phase minimum work prog | Status of licence |
|---|---|---|---|---|---|
| PL001 | Amerada Hess | Argos Resources | 1,500 Km seismic with gravity and magnetic data.Drill 2 wells to 3,500 m on 2 structures(+1 well if commercially encouraging prospects encountered) | Acquire and process additional 2D seismic to confirm prospects and leads.Acquire and process 3D Seismic to clearly define structures.Drill one exploration well on an identified commercially encouraging structure.Conduct Appraisal drilling campaign to establish size of any prospects | Still in Phase 1, which was in July 2005 extended to allow for the collection of a 3D survey. |
| PL002 | Shell | Acquire 1,000 km of 2D seismic with gravity and magnetic data.Acquire 150 km2 3D seismicDrill 2 wells (1 to 4,500 m, 1 to 3,000m)Drill 1 well dependent on commercially encouraging flow rates in the first 2 wells | No second phase work program | Relinquished 28 October 2001 relicensed as PL032 and PL033 to Rockhopper Exploration | |
| PL003 | Lasmo | Desire | Acquire 1,500 km of 2D Seismic with gravity and magnetic data.Reprocess 607 km of speculative Spectrum collected seismic.Drill 1 well to 3,000 m.Drill 2 wells conditional upon working petroleum charge in adjacent areas | Acquire and process 3D seismic.Drill 1 well.Drill further wells as appraisal of Orca or as exploration wells on further prospects defined by phase 1 seismic. | Moved to Phase 2 in May 2006 |
| PL004 | Lasmo | Desire | Acquire 1,000 km of 2D Seismic with gravity and magnetic data.Reprocess 435 km of speculative Spectrum collected seismic. | Acquire and process 3D seismic.Drill 1 well | Moved to Phase 2 in May 2006 |
| PL005 | IPC | Desire | Purchase 400 km of speculative data from Spectrum.Acquire 1,600 km of 2d seismic with gravity and magnetic data.Acquire satellite seep and gravity survey data from National Remote Sensing Centre.Drill 2 wells to 2,700 m | Acquire 800 km of 2d Seismic data or,if either of phase 1 wells proves commercial collect 500 km 2D data and 200 km2 3D data.Drill 1 exploration well on a separate structure to those drilled in phase 1 if suitable prospect found by seismic programme.Drill appraisal well to determine extent of any potentially commercial discovery. | Moved to Phase 2 October 2005 |
| PL006 | Desire | Purchase all Spectrum’s speculative data.Acquire 500 km of 2D seismic with gravity and Magnetic data.Acquire and process an additional 200 km of 2D seismic, conditional upon significant leads discovered by original survey.Reassess all existing slick survey data.Drill 1 contingent well to terminal depth appropriate to the prospect selected, conditional upon evidence of petroleum charge, identification of significant prospect and securing of farm-in partner | Drill 1 well to appropriate depth of prospect selected.Acquire additional 2D seismic with gravity and magnetic data. | Moved to Phase 2 October 2005 | |
| PL007 | Desire | Purchase all Spectrum’s speculative data.Acquire 700 km of 2D seismic with gravity and Magnetic data.Acquire and process and additional 300 km of 2D seismic, conditional upon significant leads discovered by original survey.Reassess all existing slick survey data.Drill 1 contingent well appropriate to the prospect selected, conditional upon evidence of petroleum charge, identification of significant prospect and securing of farm-in partner | Drill 1 well to appropriate depth of prospect selected.Acquire additional 2D seismic with gravity and magnetic data. | Moved to Phase 2 October 2005 | |
| PL008 PL009 PL010 PL011 PL012 PL013 PL014 PL015 PL016 PL017 |
FOGL | BHP Billiton | Initial term of 3 years:Purchase all existing seismic, magnetic and gravity data in licensed area. Acquire and process 3,500 km of 2D seismic data. Prepare a prospect evaluation report and select drillable prospects. Initial term subsequently extended to 5 years in exchange for total first phase work programme of 7,500 km of 2D data plus 2,000 km2 of 3D data, plus commitment to extra well in Phase 2. Subsequent re-negotiation of the Phase 1 work programme in June 2006 resulted in the extension of Phase 1 to 5.5 years, in exchange for an immediate 50% relinquishment of acreage held, together with a commutation of the 3D work programme in favour of a total of >14,000 km of 2D data (with at least 5000 km of new 2D data to be collected from June 2006), at least 550 km of controlled source electro-magnetic logging data and a sea bed sampling programme to test potential hydrocarbon seeps. The commitment to drill two wells in Phase 2 remains unaltered. Subsequent to BHP taking over operatorship of the licences in January 2008, the first exploration Phase was extended to December 2010 in return for a commitment to drill at least one well during this phase. |
Acquire additional 2D or 3D seismic to firm up prospects. Drill two wells to an approved objective and/or depth.Conduct post well studies and basin evaluation. Subsequent to BHP taking over operatorship of the licences in January 2008, one of the two well commitments in Phase 2 was moved forward to Phase 1. |
Still in Phase 1 except: a) PL008 Relinquished - relicensed as PL030;b) PL009 Relinquished - relicensed as PL031;c) Pl017 Relinquished A total of 50% of the licence holding as of June 2006 was relinquished in July 2006 as part of the re-negotiation of the work programme commitment. This relinquishment was spread across all 7 of the extant licences. |
| PL018 PL019 PL020 PL021 PL022 |
Borders and Southern | Initial term of 3 years:Reprocess 750 km of existing 2D seismic data within 12 months of license issue.Collect additional 2,500 km of seismic data Phase 1 was extended by two years in September 2007 in exchange for a commitment to acquire a minimum of 750 km2 of 3D seismic data. |
Acquire additional 2D or 3D seismic to firm up prospects.Drill one well to an approved objective and/or depth.Conduct post well studies and basin evaluation. | Still in Phase 1 | |
| PL023 PL024 |
Rockhopper Exploration | Initial term of 3 years:Acquire and interpret existing data over acreage, within 12 months of licence issue.Acquire 640 km of seismic data. | Acquire additional 2D or 3D seismic to firm up prospects.Drill one well to an approved objective and/or depth.Conduct post well studies and basin evaluation. | Moved to Phase 2 November 2007 | |
| PL025 PL026 PL027 PL028 PL029 |
FOGL | BHP | Initial term of 3 years:Collect 4,000 km of seismic data Subsequent to BHP taking over operatorship in January 2008, Phase 1 was extended until Dec 2010 in exchange for one well during Phase 1 in either this group of licences or in PL031 (see below). The relinquishment schedule has also been altered, with a 25% relinquishment to be made in Dec 2007, and a further 25% in December 2010 |
Acquire additional 2D or 3D seismic to firm up prospects.Drill one well to an approved objective and/or depth.Conduct post well studies and basin evaluation. Subsequent to BHP taking over operatorship, of the licences in January 2008, the Phase 2 commitments for this group of licences were merged with those for PL031 (see below) such that one well is to be drilled in Phase 2 somewhere on these combined licences. |
Still in Phase 1 |
| PL030 PL031 |
FOGL | BHP | Initial term of 3 years:Collect 1,000 km of 2D Seismic data within 12 months of licence issue.Prepare prospect evaluation report In January 2008 the Government required FOGL to relinquish PL030, in return for allowing re-alignment of the Phase 2 work programmes for the remaining licence (PL031) with licences PL025 to PL029. Subsequent to BHP taking over operatorship in January 2008, Phase 1 was extended until Dec 2010 in exchange for one well during Phase 1 in PL031 or in the group of licences PL025 to PL029 (see above). |
Acquire additional 2D or 3D seismic to firm up prospects.Drill one well to an approved objective and/or depth.Conduct post well studies and basin evaluation. Subsequent to BHP taking over operatorship, of the licences in January 2008, the Phase 2 commitments for PL031 were merged with those for PL025 to PL029 (see above) such that one well is to be drilled in Phase 2 somewhere on these combined licences. |
Still in Phase 1 |
| PL032 PL033 |
Rockhopper Exploration | Initial term of 5 Years:Collect 685 km2 3D Seismic data.Drill 1 exploration well on most attractive prospect as defined by 3D data to depth that will test early Cretaceous or Jurassic associated with mapped source rocks. | Drill 1 exploration well on most attractive prospect | Still in Phase 1 | |
| PL034 | Desire | Drill one well in the most appropriate location to test the "Alpha" prospect within 4 years. | Requirement to commit to further drilling before entering Phase 2. | Still in Phase 1 |
