See the benefits of drilling or completing wells with Cesium Formate or Potassium Formate Brines

2. www.formatebrines.com

3. Formate brines

5. 13Cr tubular from BP High Island well : 6 years exposure to 11.5 ppg formate brine packer fluid @175 o C

6. Conventional formate drilling fluid formulation - in field use since 1993 and good to 160 oC Simple, effective, non-damaging reservoir drill-in fluid Used to drill entire wells, top to bottom, in sensitive environments (e.g. Barents Sea) Component Function Concentration Formate brine Density Lubricity Polymer protection Biocide 1 bbl Xanthan Viscosity Fluid loss control 0.75 - 1 ppb Ultralow vis PAC and modified starch Fluid loss control 3 or 4 ppb of each Sized calcium carbonate Filter cake agent 20 ppb K 2 CO 3 /KHCO 3 Buffer Acid gas corrosion control 0 – 6 ppb

7. Formate-based drilling fluids

8. 1995 – Formate brines used for first time by Mobil to drill and work over deep gas wells, onshore , northern Germany Walsrode field – onshore, high-angle slim hole wells Z1, Z5, Z6 and Z7 TVD : 4,450-5,547 metres Reservoir: Sandstone 0.1-125 mD BHST : 315 o F (157 o C) Section length: 345-650 metres

9. 42 d eep HPHT gas fields developed using potassium and cesium formate brines, 1995-2011 Country Fields Reservoir Description Matrix type Depth, TVD (metres) Permeability (mD) Temperature ( o C) Germany (7) Walsrode,Sohlingen Voelkersen,I dsingen, Kalle, Weissenmoor, Simonswolde Sandstone 4,450-6,500 0.1-150 150-165 Hungary (2) Mako , Vetyem Sandstone 5,692 - 235 Kazakhstan (1) Kashagan Carbonate 4,595-5,088 - 100 Norway (10) Huldra ,Njord Kristin,Kvitebjoern Tune, Valemon Victoria, Morvin, Vega, Asgard Sandstone 4,090-7,380 50-1,000 121-200 Pakistan (2) Miano, Sawan Sandstone 3,400 10-5,000 175 Saudi Arabia (7) Andar,Shedgum Uthmaniyah Hawiyah,Haradh Tinat, Midrikah Sandstone and carbonate 3,963-4,572 0.1-40 132-154 UK (12) Braemar,Devenick Dunbar,Elgin Franklin,Glenelg Judy, Jura, Kessog Rhum, Shearwater West Franklin Sandstone 4,500-7,353 0.01-1,000 123-207 USA (1) High Island Sandstone 4,833 - 177

12. Leasing cesium formate brine Green and sustainable model – recognised by United Nations Conservation ( i.e. minimisation of cesium formate brine losses during transport, use and reclamation) is a key and essential feature of Cabot’s Chemical Leasing business model

21. Tune field – semi-HP/HT gas reservoir in the North Sea drilled and completed with formate brines 4 wells : 1,100-2,950 ft (350-900 m) horizontal reservoir sections. Suspended for 6-12 months in K/Cs formate brine after completion

22. HPHT gas fields in northern North Sea drilled and completed with cesium formate brine Almost every field development (oil and gas) on this map has used formate brines as well construction fluids . Zinc bromide brine no longer used in Europe – too hazardous and damaging

23. HPHT gas fields in the Norwegian Sea drilled and completed with cesium formate brine Formate brines also used as well construction fluids in Asgard, Draugen, Morvin and Njord fields

25. Huldra – drill-in, logging and completion times (days) with cesium formate brine in well Drill, log and run lower completion in drilling fluid. Then displace to clean cesium formate brine and run upper completion. Finally displace to packer fluid A-4 (189 m ) A-5 (263 m) A-6 (344 m) A-8 (257 m) A-9 (230 m) A-11 (336 m) Average (231 m) Drill-in 5 8 20 15 7 11 11 Logging 0 3 1 7 3 2 2.7 Lower completion 11 6 5 6 5 5 6.3 Upper completion 4 5 4 4 9 4 5 Total 20 22 30 32 24 22 25

26. Huldra – Fluid losses while drilling (cubic metres) A-4 (189 m ) A-5 (263 m) A-6 (344 m) A-8 (257 m) A-9 (230 m) A-11 (336 m) Average (231 m) With cuttings 2.6 16.4 48 9.6 23.8 17.7 19.7 Other surface 1.5 3.3 10.1 2.2 12 17.1 7.7 Downhole 7.6 10.8 46.4 0 0 0 10.8 Well displacements 5.6 28.3 12.8 24.3 11 15.7 16.3 Tripping 6.5 7.2 6.3 3.6 1.6 2.8 4.7 TOTAL 23.8 66 123.6 39.7 48.4 53.3 59.1

31. A few of the highlights from Kvitebjoern Fastest HPHT well completion in the North Sea “ The target well PI was 51,000 Sm 3 /day/bar This target would have had a skin of 7” “ A skin of 0 would have given a PI of 100,000” “ THE WELL A-04 GAVE A PI OF 90,000 Sm 3 /day/bar (ANOTHER FANTASTIC PI)” Operator comments after well testing (Q3 2004 ) The Well PI was almost double the target Kvitebjoern well Completion time (days) A-4 17.5 A-5 17.8 A-15 14.8 A-10 15.9 A-6 12.7 *

36. Cesium formate drilling fluids – some important features that impact on nuclear logging The extreme photoelectric effect of the cesium formate filtrate provides the log interpreter with valuable information regarding invasion, thus porosity and net reservoir.

37. Cesium formate drilling fluids – some important features that impact on nuclear logging Filtrate is mobile : gravity segregation over time and replacement by hydrocarbon phases Effect of invasion and time lapse : From left to right, formation density (ROBB), medium deep resistivity (P16) and deep resistivity (P40). LWD drill pass data represented by red curves and ream pass represented by black curves.

38. Logged Pef and observation of filtrate movement can be used to define permeable sands in gas reservoirs (SPE 105733) “ Using the photoelectric factor and bulk density data, combined with resistivity measurements from both the LWD drill pass and the ream pass, produces a very reliable and consistent net reservoir definition” Berg et al , SPE 105773 Log responses from drill-pass (P16_1) and ream-pass (P16_2) provide a powerful technique for defining permeable intervals (SAND_FLAG ).