Status of existing and possible new production in Greece. S. Xenopoulos, N. Roussos, Hellenic Petroleum S.A., Athens, Greece

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1 Status of existing and possible new production in Greece. S. Xenopoulos, N. Roussos, Hellenic Petroleum S.A., Athens, Greece

2 Prinos and South Kavala fields in Northern Aegean Sea, currently operated by Kavala Oil Sigma onshore facilities Prinos and Prinos North Fields South Kavala Gas field

3 Producing fields in this area Prinos Oil Field, cumulative production 113,1 MMbbls, Prinos North Oil Field, cumulative production 2,9 mil.bbls, South Kavala Gas Field, cumulative production 815 MM Nm 3 and 0,9 MM bbls of condensates,

4 Current Status Prinos Oil Field, currently producing less than 2000 bbl/d Prinos North Oil Field, Shut in since New directional well to be drilled South Kavala Gas Field, currently producing approximately Nm 3 /d

5 Prinos main reservoir top map

6 Prinos main data Reservoir depth: m, msl Producing formation : Miocene age sands No. of producing wells:21 producing wells have been drilled in total,now there are 10 active producers No. of injection wells:9 water injection wells have been drilled in total,now there are 2 active water injectors

7 Prinos North Structure

8 Prinos North main data Reservoir depth: m, msl Producing formation : Miocene age sands No. of producing wells: only 1 producinghorizontally- well was active between No. of injection wells: None In 2004 production was interrupted with the aim to drive a new horizontal production well in a different reservoir part

9 South Kavala reservoir top, ft

10 South Kavala main data Reservoir depth: m, msl Producing formation : Miocene age sands between evaporites No. of producing wells: two producing wells No. of injection wells: None

11 Description of facilities Four platforms and a flare structure are connected to the Prinos and South Kavala fields, as follows: Three platforms,two drilling and one production have been installed over Prinos field One drilling and production platform serves South Kavala Gas field Onshore facilities (Sigma Site) have been constructed 17 km from Prinos platforms to stabilize, store crude oil and to sweeten Prinos sour gas

12 Prinos Platforms

13 South Kavala Platform

14 Onshore processing facilities for crude stabilization/storage and gas sweetening

15 Other production candidates On top of Prinos,Prinos North oil fields and South Kavala gas field there are other prospects in the Gulf of Kavala that have produced oil during DST s, such as: Epsilon structure, where oil has been produced during DST s. It lies at a distance of 4 km NW from Prinos platforms Athos structure, where oil has also been produced during a DST. It lies at a distance of 9,5 km W from Prinos platforms

16 West Katakolon oil discovery

17 West Katakolon oil discovery Oil and gas has been produced from four zones by DST s in two wells West Katakolon discovery is in the Ionian Sea very close (3,5 kms) to the Katakolon peninsula off West Peloponnesus Sea depth over the reservoir is m, but distance from shore is such that an onshore deviated well could reach it

18 Exploration History 2-D seismic was shot over this area in First well (WK-1) was drilled in 1981 and recovered oil and formation water Based on this result WK-1 was deviated (WK- 1a). Oil and gas was tested at three different levels In 1982 WK-2 delineation well tested oil at two levels In D was shot over the field

19 West Katakolon -1 well Well West Katakolon-1 was drilled in 1981 with drill ship positioned at a sea depth of 73 m It reached Eocene age limestones at a depth of 2540 m,tvd,2703 m MD TD was reached at 3080 m MD with gas shows in the last 60 m Limestone top was tested bare foot. Recovery was 2%oil and formation water

20 West Katakolon -1a well Well West Katakolon-1a was diverted from WK-1 well and reached limestone higher at 2376 m TVD TD was 3218 m MD,2608 m TVD Lowest DST recovered 52% oil with drill water at 2510 m by reverse circulation Two more zones were tested higher up and recovered gas with measured flow rates up to 12 MMSCFD

21 Cross section between wells O il a nd N at u ra l G as h av e b ee n p ro d uc e d f ro m f ou r z on e s i n t wo w

22 West Katakolon -2 well Well West Katakolon-2 was drilled in m North of WK-1a well to appraise the structure Although it reached limestone 100 m lower than WK-1a,it confirmed an oil zone of 100m thickness Five DST s were ran, of which two were in the oil zone in a gross section from 2513 to 2575 m. Flow rates were between 1000 to 1400 bbl/day

23 Oil Gas properties OiI Gravity :26-28º API FVF is 1,283 BP GOR: scf/stb SG of Gas is 0,72.It contains H 2 S and CO 2 5,4 and 8,8 mole % respectively

24 Thickness of oil and gas zones Well test results and plotting of formation pressures versus depth has led to the following conclusions: Gas zone has a thickness of +/- 120m from reservoir crest Oil zone has a gross thickness of m

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26 3-D survey over the field A 3-D seismic survey was ran in 1984 in an area of approximately 100 km 2,covering the field and another prospect to the South East (South Katakolon prospect) Gross Bulk Volume in the Hydrocarbon wet area was increased by 15% A structure South of the Evaporite is confirmed by the Seismic Interpretation

27 West Katakolon structure top

28 Possibility to reach West Katakolon by an onshore deviated well Since distance of West Katakolon field from shore is only 3,5 km, an onshore well from the small Katakolon peninsula could be directionally drilled, reaching West Katakolon structure with a 500 m horizontal section through the reservoir, with a MD of +/ m Having available this onshore well a long term test would help to improve knowledge of reservoir characteristics

29 Old 105 well site is only 700 m far from peninsula's tip Site of old onshore 105 well that could be used as a starting point to drill new West Katakolon delineation well

30 Epanomi Gas discovery

31 Epanomi key facts It lies very close to the sea at a distance of 30 km from Thessalonica Two wells have been drilled over this structure Gas was tested in these wells from a gas bearing zone at a depth from 2600 to 2800 m Reservoir rock is a fractured mesozoic limestone as per following slide Buried paleo-high structure

32 2-D section over Epanomi discovery

33 Composite stratigrapy in Epanomi wells

34 Epanomi area well test results Two wells were drilled in in Epanomi over the same reservoir. Natural gas was recovered from DST s in both wells Natural gas composition was pretty similar in both wells. Non combustible components, CO 2 (21%) and N 2 (8%) are reducing gas quality

35 Flow rates from Epanomi wells Epanomi-1:Natural gas flowed at rates up to 7,7 MMSFD from Jurassic limestones (LS), but flow duration could not be prolonged. At LS top, where a 17 m Eocene LS layer was drilled, there was a much smaller flow rate of 0,2 MMSCFD Epanomi-2 :Higher gas flow rates were measured in DST s from Jurassic LS up to 15,7 MMSCFD with bbl/day of condensate In both wells there were additional DST s that produced formation water, delineating thus vertical extension of the gas zone

36 Plotting all formation pressures a Gas Water contact at +/ m could be recognized

37 Shore line Epanomi structure map

38 Epanomi development options Epanomi gas could be utilized for electrical power generation Further exploration in the area could modify these plans, since a prospect 10 km to the North of Epanomi could well add more gas reserves in the area On top of that additional 2-D seismic could reveal a stratigraphic play 2-3 kms West of Epanomi.