Bolaget ansöker om klassificering av C1 & C2 reserver

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Interfox Resources ryska projektbolag, BNG, ansöker om registrering av 38 miljoner fat (5 miljoner ton) reserver kategori C1 & C2 av oljeekvivalenter.

Huvudsakligen på grund av de mycket goda resultat som erhölls från den s k vittringsskorpan (enligt tidigare pressmeddelanden), har BNG redan nu möjlighet att ansöka om registrering av reserver under kategori C1 & C2. Detta görs hos den ryska myndigheten GKZ vid naturresursministeriet. Processen och utvärderingen kommer att pågå under maj-oktober 2015, varefter GKZ kommer att registrera de godkända volymerna. BNG kommer att ansöka om registrering av 38 miljoner fat (5 miljoner ton) oljeekvivalenter (boe), dvs olja och gas sammanslagna och omräknade som om det vore endast olja.

Registrering av reserver kommer även till att leda till att myndigheterna utfärdar ett ”Certificate for discovery of a new hydrocarbon field”.

C1 & C2 utgör de högsta kategorierna av klassificering av utvinningsbara kolväten. Under rådande oljepris, betingar de normalt ett värde på USD 1,5-2,0 per fat när de säljs i marken, dvs utan någon utbyggnad av produktion. Det är försäljning av reserver i marken som är Interfox Resources exitstrategi.

Vid den föregående ansökan, för registrering av 132 miljoner boe C3 resurser, godkände myndigheten helt BNG's beräkningar. De nya beräkningarna är gjorda av samma team och enligt samma principer.

Den nya brunn som Bolaget avser att borra under första halvåret 2016 har till syfte att omvandla ytterligare del av ovan nämnda C3 resurser till C1 & C2 reserver.

UPPDATERING INTERFOX, BNG & FÖRHANDLINGAR

Med anledningar av den förändrade tidplanen vill styrelsen göra följande förtydliganden.

Interfox Resources är finansiellt sunt. Bolaget har pengar i kassan och inga skulder och kan därför klara kommande utgifter under de kommande 12 månaderna.

I BNG önskar man fortsätta med vissa aktiviteter i re-entry brunn (#4) även innan finansieringen av den nya brunnen är säkrad. Avsikten är att lösa detta med lokala ryska banklån till BNG. Detta kan vara möjligt baserat på ovanstående ansökan av registrering av reserver samt under förutsättning att BNG omedelbart omvandlar de tillskott gjorda av Interfox Resources till eget kapital. Peter Klimt, vd, har påbörjat processen med det sistnämnda.

Förhandlingarna med två tilltänkta asiatiska partners för finansieringen av den nya brunnen pågår med oförändrad intensitet. Bolaget valde att avvakta i väntan på att förutsättningarna för ansökan om reserver blev uppfyllda, eftersom detta påverkar dynamiken i förhandlingarna. Det är inte sannolikt att Bolaget kan publicera några konkreta resultat före juli 2015. Detta ligger dock gott och väl inom ramen för den allmänna planen, eftersom arbetet med den nya brunnen kan påbörjas först när vintervägarna åter öppnar 2016-01-01.

Båda intressenterna genomför nu en teknisk due diligence. En executive summary av det tekniska materialet bifogas detta pressmeddelande (även om det mesta av informationen publicerats tidigare i diverse pressmeddelanden).

För ytterligare information, vänligen kontakta:

Anders Thorsell, styrelseledamot

Tel: +46 70 773 20 45

Email: anders@interfox.com

Fakta om Interfox Resources AB (publ):

Interfox Resources är ett bolag med inriktning på prospektering avseende olja och gas i Ryssland. I Ryssland kontrollerar bolaget en licens i Tomskregionen i västra Sibirien, Ellej-Igaiskoje 71-1. Bolaget genomför ett arbetsprogram i syfte att omvandla resurser till reserver.

Interfox Resources aktie handlas på Aktietorget under namnet IFOX.

Brief geological description of Yelley-Igaiskaya area

Administratively Yelley-Igaiskaya area is situated on the territory of Yelley-Igaiskiy license block which is situated in Kargasok region of Tomsk Oblast. The distance from Tomsk is 430 km, and 100 km from the town of Kedroviy.

The block forms part of Mezhovskiy oil and gas bearing province of Vasyugan oil and gas suite. Tectonically the areas of interest is situated in Lavrovskiy inclining shaft.

Understanding of the area by seismic survey CMP - 1,27 km/km2, by deep drilling - 248,5 m/km2. 2D CMP seismic exploration works were carried out in surveying seasons of 1974-1975 and 1980-1981.

In 1990s 2 stratigraphic wells were drilled within the area: well 2 and well 4. Well 2 as of 01.11.2014 is abandoned, well 4 was re-entered in 2014. OOO “Bakcharneftegaz” performs control of the technical state of the well stock, including those abandoned situated within the license block in compliance with operational documentation RD 08-492-02 and schedule of examination of wellheads of abandoned wells on the territory of Yelley-Igaiskiy license block (Application 100). During the time when operations were performed within the license block, no violations of regulatory documentation were found.

Stratigraphic well 2 was drilled to the depth of 4502 m. Paleozoic deposits were penetrated at the interval of 3005-4502 m.

Evidence of oil and gas were marked in the intervals of 3370-3374 m (gas showings and oil film in the mud), 4083,8-4089,5 m (smell of condensate in core samples).

Stratigraphic well 4 was drilled to the depth of 4100 m. Paleozoic deposits were penetrated at 2975 m.

Evidence of oil and gas in Paleozoic deposits were marked in the following intervals: 3028-3040 m, 3710-3720 m, 3747-3754 m, 3832-3842 m, 3872-3883 m, 3950-3955 m.

Both wells were drilled in South-West part of Yelley-Igaiskaya structure, main part of which lies at adjacent Yuzhno-Urmansky license block (license TOM 11405 NP).

For the territory under exploration finding oil and gas perspective zones of fissures cavernous porous carbonate reservoirs not only in the upper part of pre-Jurassic complex but at deeper horizons is of current interest.

Most perspective in terms of oil and gas are organogenic (bioherm) buildups containing permeable partings, presence of which is identified in cross section of well 2, as well as weathered crust of Paleozoic.

OOO “Bakcharneftegaz” performs geological exploration and design operations at Yelley-Igaiskaya area, Yelley-Igaiskiy license block (71-1).

Ongoing and fulfilled operations:

- designing geological exploration works;

- re-processing and re-interpretation of seismic, geophysical materials of past years;

- restoring stratigraphic well 4 of Yelley-Igayskiy license block;

-geophysical exploration of well 4 of Yelley-Igayskiy license block;

- testing of perspective objects by perforation techniques with flow enhancement via bottomhole zone treatment (chemical BHT) in well 4;

- in the future – construction of prospecting and appraisal well 7 at Yelley-Igaiskiy license block 4340 m deep.

Due to complication of identifying reservoir intervals of fissures of cavernous type as well as hydrocarbon saturations in carbonate deposits of Paleozoic, the decision was made to carry out a complex of geophysical surveys jointly with OOO “IOGT”. In the course of works the following innovative technologies of OOO “IOGT” were applied: technologies designed to evaluate technical condition of steel support and cementing of the well and inspect hydrocarbon saturation of reservoirs based on methods of magnetic pulse scanning NDT and nuclear logging, namely:

Diagnostics of well support state:

• well construction specification;

• thickness and defect measurement of protective casing, production string and tubing;

     • identifying condition of cement sheath;

• study of thermobaric condition of the well.

Inspection of active reservoirs:

• lithology differentiation;

• reservoir identification;

• identifying fluid content of reservoirs;

• identifying of oil and gas saturation factors of reservoirs.

Methodology of OOO “IOGT” made it possible to identify the above stated parameters for carbonate deposits of Paleozoic in the context of a cased well which, in its turn, allowed to understand well subsurface structure, evaluate possible behind-the-casing flow, and, at the end of the day, correct the boundaries of prospective zones saturated with hydrocarbons.

Works on subsurface geological study on the territory of Yelley-Igaiskiy license block are carried out in accordance with requirements of the License Agreement according to the appraisal program on the territory of Yelley-Igaiskiy license block of Tomsk Oblast.

OOO “Bakcharneftegaz” owns the license for the right to use subsurface mineral resources TOM 01559 NR with the purpose of geological survey, exploration and production of hydrocarbons - Yelley-Igaiskiy license block, Kargasok Region, Tomsk Oblast. License expiry date is 30.09.2035. The license block represented by the mineral license is situated on the territory of Kargasok Region of Tomsk Oblast, Russian Federation. The lower boundary of the license block is not limited by depth. The total projected area of the license block makes 34,59 km2.

According to conditions of the License Agreement, re-processing and reinterpretation of seismic, geophysical material of the past years was carried out, report of “Reinterpretation of logging data at deep wells, re-processing and complex reinterpretation of CMP-2D materials with regard to drilling and logging data within South-West flank of Yelley-Igaiskiy uplift” (license block 71-1) was prepared by subcontractor OOO “GeoPrime” branch - “Tomsk Geophysical Company”. State registration 69-12-403. Approved by the General Director of OOO“Bakcharneftegaz” M. Yu. Malyarenko on 18.01.2013. Based on the results of re-processing and reinterpretation of seismic, geophysical materials of the past years, calculation of prospective resources was made and passport for Yelley-Igaiskaya trap was prepared.

Gas resources calculation (Qg) was done based on the following equation:

Qg = F x Нnp х Кp х β х f (Рin х α Рfin х αk),

where F – area of assumed accumulation within the boundaries of the license blocvk, thousands of m2;

- Нnp – net pay thickness, m;

- Cp – porosity coefficient, unit fraction;

- β – gas saturation coefficient, unit fraction, assumed by analogy with Archinskoye field;

- f – temperature correction, unit fraction, assumed by analogy with Archinskoye field;

- Рin – initial reservoir pressure in accumulation, mPa, assumed equal to hydrostatic;

- Рfin. – residual reservoir pressure in accumulation, mPa, assumed to be equal to 0.12 mPa by analogy with Archinskoye field;

- α =1.1 и αk=1, unit fraction – corrections for deviation of hydrocarbon gases from Boyle’s/Mariotte’s law, assumed by analogy with Archinskoye field.

Condensate resources calculation (Qc) was done using the equation below:

Qc = Qg х Cf хYc х ŋc,

where    

- Qg – gas resources, mln of m3;

- Cf – condensate factor, sm3/m3, assumed by analogy with Archinskoye field;

- Yc – condensate gravity, g/sm3, based on sample taken from well 2 of Yelley-Igaiskaya area;

- ŋc – condensate recovery factor, unit fraction, assumed by analogy with Archinskoye field.

Gas saturation zones in the marked accumulations were calculated based on the results of mapping and prediction of reservoir development within the boundaries of potential hydrocarbon areas and within the boundaries of the license block.

Net pay thicknesses of potential accumulations are assumed in the volumes of permeable zones as identified by geophysical survey (average value for wells 2 and 4) and seismic prediction.

Open porosity factor according to geophysical survey (wells 2 and 4 at Yelley-Igaiskaya area) amounts 3–13.7% . The given values do not take into account the presence of open fractures and caverns in the reservoir. Survey of void space applying state-of-the-art methods were not carried out on the area. Lithological and petrographic rock characteristics allow to label them as porous fractured reservoirs having average values of live capacity and flow properties (Cp= 12-25%, group B, grade 5) according to “Evaluation-genetic classification of carbonate reservoirs” (Bagrintseva K.I., 1989).

In order to calculate resources, open porosity factor (Cp) was assumed by analogy with Archinskoye field (from reserves calculation dat) as – 0.21 unit fraction.

Results of resources calculation are summarized in the tables 1, 2.

In such a way, with relatively high degree of possibility it can be stated that 16.5 bn cubic meters of gas and ~1.8 mln tons of condensate correspondingly are deposited in Yelley-Igaiskiy carbonate formation.

GeoPrime’s assessment before re-entry was that most likely, liquid hydrocarbons phase will be represented by a mixture of condensate and oil.

Calculation of gas prospective resources at Yelley-Igaiskiy license

block 71-1 of C3 category

(See table in enclosed pdf)

Calculation of condensate prospective resources at Yelley-Igaiskiy license

block 71-1 of C3 category

(See table in enclosed pdf)

Fulfillment of all scope of works on hydrocarbons search and valuation in compliance with approved “Program of prospecting and evaluation works at Yelley-Igaiskiy license block” is established by the license requirements until the stage of geological exploration is finished, being limited by the period of five years from the date of license state registration (07.10.2010). Before the five years are out from the date of license state registration the operator company is to submit information report about the results of works performed at the block to local Rosnedra company. Not later than six months before the expiry of the period of five years from the date of license state registration the operator company is to submit a written request about intention (if any) to continue prospecting and evaluation works on separate prospective areas with mentioning their boundaries, additional volumes, types and terms of works to local Rosnedra company.

Works on the territory of Yelley-Igaiskiy license block 71-1 were planned and fulfilled with regard to:

Program of prospecting and evaluation works on the territory of Yelley-Igaiskiy license block of Tomsk Oblast (2012).

Project of geophysical prospecting (search for reservoirs) for oil and gas at Yelley-Igaiskaya area of Yelley-Igaiskiy license block of Tomsk Oblast (2014).

Project of reentry into stratigraphic well 4 of Yelley-Igaiskaya area of Yelley-Igaiskiy license block (2014).

Technical report about engineering surveys carried out at the area “Construction of appraisal well 7 at Yelley-Igaiskaya area of Yelley-Igaiskiy license block (71-1) in Kargasok region of Tomsk Oblast (2014).

License requirements do not stipulate performance of any volume of drilling operations at the stage of prospecting works, in particular, in 2015. Based on the results of all the range of works carried out on prospecting and evaluation of hydrocarbon fields in compliance with approved “Program of prospecting and evaluation works on the territory of Yelley-Igaiskiy license block” the decision will be made on drilling one appraisal well. Preliminary decision is to start drilling one appraisal well 7, total volume of works is 4340 linear running meters.

In case of field discovery within the boundaries of geological allotment, the license holder is obliged to carry out range of works, such as but not limited to point 3.3.3 –

“Not later than the second year from the date of field discovery to start performing seismic exploration works (2D or 3D) or drilling an exploration well within the boundaries of the discovered field.”

Geological and technical actions: those already carried out and those planned for the future:

As of 10.04.2015, recovery of well 4 according to the project for recovery of stratigraphic well 4 of Yelley-Igaiskaya area at Yelley-Igaiskiy license block was carried out by OOO “Bakcharneftegaz” (positive findings of HSE expertise 014/12-12- PD/NG/657, reg. 60-ED-62299-2012, OOOTomsk engineering and technical center”). In compliance with schedules worked out on testing objects, testing of the seven objects was carried out using perforation methods with flow enhancement via bottomhole zone treatment (with chemicals), cement bridge was set in perforation interval of the edge testing object – weathered crust of Paleozoic (2990-3000 m).

Perforating and blasting operations, borehole geophysical survey were performed by “Siberian field trial geophysical expedition”, the branch of “Sibneftegeophysics” (based on the contract 35-2012 dated 26.12.2012.

  1. Geophysical survey, perforating and blasting operations (perforation, fluid movement profile, injection profile, tying in packers, etc.) during testing well 4.
  1. Well test operations while testing well 4.
  1. Well stimulation via bottomhole zone treatment (by chemicals).

4.   Well suspension (abandonment) upon termination of testing operations on well 4.

5.   Geophysical survey, perforating and blasting operations (including openhole logging, perforation, fluid movement profile, injection profile, tying in packers, etc.) are planned while drilling well 7.

6.   Well test operations while drilling and testing well 7.

7.     Well stimulation via bottomhole zone treatment (by chemicals).

8.   Pilot production in case of commercial inflow of hydrocarbons.

Findings:

The main result of testing well 4 of Yelley-Igaiskaya area is obtaining commercial inflow of gas, as well as inflow of liquid hydrocarbons represented by condensate from the weathered crust of Paleozoic (2990-3000 m).

Results of testing 6 objects of core Paleozoic demonstrating presence of gas, as well as detailed description of technological operations, are stated in acts of testing objects 1-6, act of testing object 7 is being prepared at the moment.

Key points of testing should be mentioned briefly. When performing acid treatment, gas showings were observed in all the tested objects from zones treated with acid directly proportional to volume of agent pumped in. When joint testing of the second and the third object intervals during flow enhancement through pressurizing up to 320 ATM, excess pressure growth was observed in tubing up to 50 and 20 ATM accompanied by generation of gas cap.   When joint testing of object intervals 10, 11, and 12 after acid treatment fluid overflow through tubing was observed. The overflow was accompanied by gas showings (the gas was flammable). The well produced to the flare pit through 5 and 3 mm chokes. Initial overflow rate made 0,83 m3/hour. In five hours and 45 minutes the overflow stopped. Total volume of fluid produced from the well (by overflowing) ~ 2m3.

It should be mentioned that while drilling the well, most fractured and permeable intervals, most probably, absorbed big amounts of drilling mud, which, in its turn, reduced by times or even to zero, filtration capacity of oil and gas bearing zones. The depth of drilling mud invasion is difficult to evaluate. In order to reduce drilling mud effect (skin-effect reduction), as well as improve reservoir connectivity, hydraulic fracturing with filling fractures with proppant is recommended.

When testing object 6 comprising two prospective intervals (3028-3060 m, 3090-3093 m), in December 2014 – January 2015 overflow of technical water was received after perforation job and reduction of swabbing level till depth of 600 m, and the well started cleaning. Because of proximity to hazardous object (weathered crust of Paleozoic) the decision was made to identify injectivity profile in perforation interval in order to identify chances of killing the well in case of receiving abnormally high wellhead pressures (300-350 ATM). According to current field information, two gas discharging intervals were identified (3028-3060 m, 3090-3093 m), as well as one intaking interval (3040-3046 m), characterized by really high flow properties. Injectivity of intaking interval according to the results of field geophysical test, is about 230 m3/day. In such a way, for the first time since the starting moment of testing well 4 of Yelley-Igaiskaya area a reservoir was found in Paleozoic deposits having high flow properties.

On 11.02.2015 commercial inflow of hydrocarbons was received while testing object 7 from deposits of weathered crust of Paleozoic (perforation interval 2990-3000 m).

On 14.02.2015 the flowrate of gas condensate mixture made 114 thousand m3 while the well was producing through a 12 mm choke.

During producing the well through orifice gauge of critical flow with 12-16 mm chokes with the purpose of flushing the bottomhole zone from solids, intense recovery of solids, presumably, reservoir rock debris from near wellbore zone was observed, which makes it possible to draw the conclusion about the presence of a reservoir which is characterized by absolute permeability of more than a 100 mD (0,1 microns), which is also confirmed by absence of core while drilling.

After killing the well, as a result of well reverse circulation 60 liters of cuttings were recovered on surface from the near wellbore zone (rounded cuttings of rocks constituting weathered crust, cuttings of the cement rock, etc. up to 28 mm in size). This fact can also serve as justification of presence of a highly permeable thickness. The debris recovered were sent for laboratory analysis with the purpose of identifying the age of rocks and their mineral composition.

Well test was carried out, 4 well operating modes were tested at different chokes, pressure buildup, samples of gas, stable condensate and associate water were taken. Laboratory analysis of associate water was carried out. Condensate samples were sent for laboratory analysis.

Detailed description of technological operations when testing object 7 will comprise act for testing object 7 which is currently is at the stage of being prepared.

Based on the information received, such as re-processing and reinterpretation of seismic data which were obtained in past years and geophysical survey data taken from appraisal and stratigraphic wells drilled in past years, as well as well test data of well 4, receiving commercial inflow of hydrocarbons in well 4 from object 7 (interval of 2990-3000 m, weathered crust), reservoir fluids sample analysis (separator gas, condensate, reservoir water), the company possesses enough data in order to prepare Current estimation of hydrocarbon reserves of Yelley-Igaiskaya area in categories of С1 + С2 according to Russian reserves classification followed by receiving Field Discovery Certificate.

(See table in enclosed pdf)

Huvudsakligen på grund av de mycket goda resultat som erhölls från den s k vittringsskorpan (enligt tidigare pressmeddelanden), har BNG redan nu möjlighet att ansöka om registrering av reserver under kategori C1 & C2. Detta görs hos den ryska myndigheten GKZ vid naturresursministeriet. Processen och utvärderingen kommer att pågå under maj-oktober 2015, varefter GKZ kommer att registrera de godkända volymerna. BNG kommer att ansöka om registrering av 38 miljoner fat (5 miljoner ton) oljeekvivalenter (boe), dvs olja och gas sammanslagna och omräknade som om det vore endast olja.

Registrering av reserver kommer även till att leda till att myndigheterna utfärdar ett ”Certificate for discovery of a new hydrocarbon field”.

C1 & C2 utgör de högsta kategorierna av klassificering av utvinningsbara kolväten. Under rådande oljepris, betingar de normalt ett värde på USD 1,5-2,0 per fat när de säljs i marken, dvs utan någon utbyggnad av produktion. Det är försäljning av reserver i marken som är Interfox Resources exitstrategi.

Vid den föregående ansökan, för registrering av 132 miljoner boe C3 resurser, godkände myndigheten helt BNG's beräkningar. De nya beräkningarna är gjorda av samma team och enligt samma principer.

Den nya brunn som Bolaget avser att borra under första halvåret 2016 har till syfte att omvandla ytterligare del av ovan nämnda C3 resurser till C1 & C2 reserver.

UPPDATERING INTERFOX, BNG & FÖRHANDLINGAR

Med anledningar av den förändrade tidplanen vill styrelsen göra följande förtydliganden.

Interfox Resources är finansiellt sunt. Bolaget har pengar i kassan och inga skulder och kan därför klara kommande utgifter under de kommande 12 månaderna.

I BNG önskar man fortsätta med vissa aktiviteter i re-entry brunn (#4) även innan finansieringen av den nya brunnen är säkrad. Avsikten är att lösa detta med lokala ryska banklån till BNG. Detta kan vara möjligt baserat på ovanstående ansökan av registrering av reserver samt under förutsättning att BNG omedelbart omvandlar de tillskott gjorda av Interfox Resources till eget kapital. Peter Klimt, vd, har påbörjat processen med det sistnämnda.

Förhandlingarna med två tilltänkta asiatiska partners för finansieringen av den nya brunnen pågår med oförändrad intensitet. Bolaget valde att avvakta i väntan på att förutsättningarna för ansökan om reserver blev uppfyllda, eftersom detta påverkar dynamiken i förhandlingarna. Det är inte sannolikt att Bolaget kan publicera några konkreta resultat före juli 2015. Detta ligger dock gott och väl inom ramen för den allmänna planen, eftersom arbetet med den nya brunnen kan påbörjas först när vintervägarna åter öppnar 2016-01-01.

Båda intressenterna genomför nu en teknisk due diligence. En executive summary av det tekniska materialet bifogas detta pressmeddelande (även om det mesta av informationen publicerats tidigare i diverse pressmeddelanden).

För ytterligare information, vänligen kontakta:

Anders Thorsell, styrelseledamot

Tel: +46 70 773 20 45

Email: anders@interfox.com

Fakta om Interfox Resources AB (publ):

Interfox Resources är ett bolag med inriktning på prospektering avseende olja och gas i Ryssland. I Ryssland kontrollerar bolaget en licens i Tomskregionen i västra Sibirien, Ellej-Igaiskoje 71-1. Bolaget genomför ett arbetsprogram i syfte att omvandla resurser till reserver.

Interfox Resources aktie handlas på Aktietorget under namnet IFOX.

Brief geological description of Yelley-Igaiskaya area

Administratively Yelley-Igaiskaya area is situated on the territory of Yelley-Igaiskiy license block which is situated in Kargasok region of Tomsk Oblast. The distance from Tomsk is 430 km, and 100 km from the town of Kedroviy.

The block forms part of Mezhovskiy oil and gas bearing province of Vasyugan oil and gas suite. Tectonically the areas of interest is situated in Lavrovskiy inclining shaft.

Understanding of the area by seismic survey CMP - 1,27 km/km2, by deep drilling - 248,5 m/km2. 2D CMP seismic exploration works were carried out in surveying seasons of 1974-1975 and 1980-1981.

In 1990s 2 stratigraphic wells were drilled within the area: well 2 and well 4. Well 2 as of 01.11.2014 is abandoned, well 4 was re-entered in 2014. OOO “Bakcharneftegaz” performs control of the technical state of the well stock, including those abandoned situated within the license block in compliance with operational documentation RD 08-492-02 and schedule of examination of wellheads of abandoned wells on the territory of Yelley-Igaiskiy license block (Application 100). During the time when operations were performed within the license block, no violations of regulatory documentation were found.

Stratigraphic well 2 was drilled to the depth of 4502 m. Paleozoic deposits were penetrated at the interval of 3005-4502 m.

Evidence of oil and gas were marked in the intervals of 3370-3374 m (gas showings and oil film in the mud), 4083,8-4089,5 m (smell of condensate in core samples).

Stratigraphic well 4 was drilled to the depth of 4100 m. Paleozoic deposits were penetrated at 2975 m.

Evidence of oil and gas in Paleozoic deposits were marked in the following intervals: 3028-3040 m, 3710-3720 m, 3747-3754 m, 3832-3842 m, 3872-3883 m, 3950-3955 m.

Both wells were drilled in South-West part of Yelley-Igaiskaya structure, main part of which lies at adjacent Yuzhno-Urmansky license block (license TOM 11405 NP).

For the territory under exploration finding oil and gas perspective zones of fissures cavernous porous carbonate reservoirs not only in the upper part of pre-Jurassic complex but at deeper horizons is of current interest.

Most perspective in terms of oil and gas are organogenic (bioherm) buildups containing permeable partings, presence of which is identified in cross section of well 2, as well as weathered crust of Paleozoic.

OOO “Bakcharneftegaz” performs geological exploration and design operations at Yelley-Igaiskaya area, Yelley-Igaiskiy license block (71-1).

Ongoing and fulfilled operations:

- designing geological exploration works;

- re-processing and re-interpretation of seismic, geophysical materials of past years;

- restoring stratigraphic well 4 of Yelley-Igayskiy license block;

-geophysical exploration of well 4 of Yelley-Igayskiy license block;

- testing of perspective objects by perforation techniques with flow enhancement via bottomhole zone treatment (chemical BHT) in well 4;

- in the future – construction of prospecting and appraisal well 7 at Yelley-Igaiskiy license block 4340 m deep.

Due to complication of identifying reservoir intervals of fissures of cavernous type as well as hydrocarbon saturations in carbonate deposits of Paleozoic, the decision was made to carry out a complex of geophysical surveys jointly with OOO “IOGT”. In the course of works the following innovative technologies of OOO “IOGT” were applied: technologies designed to evaluate technical condition of steel support and cementing of the well and inspect hydrocarbon saturation of reservoirs based on methods of magnetic pulse scanning NDT and nuclear logging, namely:

Diagnostics of well support state:

• well construction specification;

• thickness and defect measurement of protective casing, production string and tubing;

     • identifying condition of cement sheath;

• study of thermobaric condition of the well.

Inspection of active reservoirs:

• lithology differentiation;

• reservoir identification;

• identifying fluid content of reservoirs;

• identifying of oil and gas saturation factors of reservoirs.

Methodology of OOO “IOGT” made it possible to identify the above stated parameters for carbonate deposits of Paleozoic in the context of a cased well which, in its turn, allowed to understand well subsurface structure, evaluate possible behind-the-casing flow, and, at the end of the day, correct the boundaries of prospective zones saturated with hydrocarbons.

Works on subsurface geological study on the territory of Yelley-Igaiskiy license block are carried out in accordance with requirements of the License Agreement according to the appraisal program on the territory of Yelley-Igaiskiy license block of Tomsk Oblast.

OOO “Bakcharneftegaz” owns the license for the right to use subsurface mineral resources TOM 01559 NR with the purpose of geological survey, exploration and production of hydrocarbons - Yelley-Igaiskiy license block, Kargasok Region, Tomsk Oblast. License expiry date is 30.09.2035. The license block represented by the mineral license is situated on the territory of Kargasok Region of Tomsk Oblast, Russian Federation. The lower boundary of the license block is not limited by depth. The total projected area of the license block makes 34,59 km2.

According to conditions of the License Agreement, re-processing and reinterpretation of seismic, geophysical material of the past years was carried out, report of “Reinterpretation of logging data at deep wells, re-processing and complex reinterpretation of CMP-2D materials with regard to drilling and logging data within South-West flank of Yelley-Igaiskiy uplift” (license block 71-1) was prepared by subcontractor OOO “GeoPrime” branch - “Tomsk Geophysical Company”. State registration 69-12-403. Approved by the General Director of OOO“Bakcharneftegaz” M. Yu. Malyarenko on 18.01.2013. Based on the results of re-processing and reinterpretation of seismic, geophysical materials of the past years, calculation of prospective resources was made and passport for Yelley-Igaiskaya trap was prepared.

Gas resources calculation (Qg) was done based on the following equation:

Qg = F x Нnp х Кp х β х f (Рin х α Рfin х αk),

where F – area of assumed accumulation within the boundaries of the license blocvk, thousands of m2;

- Нnp – net pay thickness, m;

- Cp – porosity coefficient, unit fraction;

- β – gas saturation coefficient, unit fraction, assumed by analogy with Archinskoye field;

- f – temperature correction, unit fraction, assumed by analogy with Archinskoye field;

- Рin – initial reservoir pressure in accumulation, mPa, assumed equal to hydrostatic;

- Рfin. – residual reservoir pressure in accumulation, mPa, assumed to be equal to 0.12 mPa by analogy with Archinskoye field;

- α =1.1 и αk=1, unit fraction – corrections for deviation of hydrocarbon gases from Boyle’s/Mariotte’s law, assumed by analogy with Archinskoye field.

Condensate resources calculation (Qc) was done using the equation below:

Qc = Qg х Cf хYc х ŋc,

where    

- Qg – gas resources, mln of m3;

- Cf – condensate factor, sm3/m3, assumed by analogy with Archinskoye field;

- Yc – condensate gravity, g/sm3, based on sample taken from well 2 of Yelley-Igaiskaya area;

- ŋc – condensate recovery factor, unit fraction, assumed by analogy with Archinskoye field.

Gas saturation zones in the marked accumulations were calculated based on the results of mapping and prediction of reservoir development within the boundaries of potential hydrocarbon areas and within the boundaries of the license block.

Net pay thicknesses of potential accumulations are assumed in the volumes of permeable zones as identified by geophysical survey (average value for wells 2 and 4) and seismic prediction.

Open porosity factor according to geophysical survey (wells 2 and 4 at Yelley-Igaiskaya area) amounts 3–13.7% . The given values do not take into account the presence of open fractures and caverns in the reservoir. Survey of void space applying state-of-the-art methods were not carried out on the area. Lithological and petrographic rock characteristics allow to label them as porous fractured reservoirs having average values of live capacity and flow properties (Cp= 12-25%, group B, grade 5) according to “Evaluation-genetic classification of carbonate reservoirs” (Bagrintseva K.I., 1989).

In order to calculate resources, open porosity factor (Cp) was assumed by analogy with Archinskoye field (from reserves calculation dat) as – 0.21 unit fraction.

Results of resources calculation are summarized in the tables 1, 2.

In such a way, with relatively high degree of possibility it can be stated that 16.5 bn cubic meters of gas and ~1.8 mln tons of condensate correspondingly are deposited in Yelley-Igaiskiy carbonate formation.

GeoPrime’s assessment before re-entry was that most likely, liquid hydrocarbons phase will be represented by a mixture of condensate and oil.

Calculation of gas prospective resources at Yelley-Igaiskiy license

block 71-1 of C3 category

(See table in enclosed pdf)

Calculation of condensate prospective resources at Yelley-Igaiskiy license

block 71-1 of C3 category

(See table in enclosed pdf)

Fulfillment of all scope of works on hydrocarbons search and valuation in compliance with approved “Program of prospecting and evaluation works at Yelley-Igaiskiy license block” is established by the license requirements until the stage of geological exploration is finished, being limited by the period of five years from the date of license state registration (07.10.2010). Before the five years are out from the date of license state registration the operator company is to submit information report about the results of works performed at the block to local Rosnedra company. Not later than six months before the expiry of the period of five years from the date of license state registration the operator company is to submit a written request about intention (if any) to continue prospecting and evaluation works on separate prospective areas with mentioning their boundaries, additional volumes, types and terms of works to local Rosnedra company.

Works on the territory of Yelley-Igaiskiy license block 71-1 were planned and fulfilled with regard to:

Program of prospecting and evaluation works on the territory of Yelley-Igaiskiy license block of Tomsk Oblast (2012).

Project of geophysical prospecting (search for reservoirs) for oil and gas at Yelley-Igaiskaya area of Yelley-Igaiskiy license block of Tomsk Oblast (2014).

Project of reentry into stratigraphic well 4 of Yelley-Igaiskaya area of Yelley-Igaiskiy license block (2014).

Technical report about engineering surveys carried out at the area “Construction of appraisal well 7 at Yelley-Igaiskaya area of Yelley-Igaiskiy license block (71-1) in Kargasok region of Tomsk Oblast (2014).

License requirements do not stipulate performance of any volume of drilling operations at the stage of prospecting works, in particular, in 2015. Based on the results of all the range of works carried out on prospecting and evaluation of hydrocarbon fields in compliance with approved “Program of prospecting and evaluation works on the territory of Yelley-Igaiskiy license block” the decision will be made on drilling one appraisal well. Preliminary decision is to start drilling one appraisal well 7, total volume of works is 4340 linear running meters.

In case of field discovery within the boundaries of geological allotment, the license holder is obliged to carry out range of works, such as but not limited to point 3.3.3 –

“Not later than the second year from the date of field discovery to start performing seismic exploration works (2D or 3D) or drilling an exploration well within the boundaries of the discovered field.”

Geological and technical actions: those already carried out and those planned for the future:

As of 10.04.2015, recovery of well 4 according to the project for recovery of stratigraphic well 4 of Yelley-Igaiskaya area at Yelley-Igaiskiy license block was carried out by OOO “Bakcharneftegaz” (positive findings of HSE expertise 014/12-12- PD/NG/657, reg. 60-ED-62299-2012, OOOTomsk engineering and technical center”). In compliance with schedules worked out on testing objects, testing of the seven objects was carried out using perforation methods with flow enhancement via bottomhole zone treatment (with chemicals), cement bridge was set in perforation interval of the edge testing object – weathered crust of Paleozoic (2990-3000 m).

Perforating and blasting operations, borehole geophysical survey were performed by “Siberian field trial geophysical expedition”, the branch of “Sibneftegeophysics” (based on the contract 35-2012 dated 26.12.2012.

  1. Geophysical survey, perforating and blasting operations (perforation, fluid movement profile, injection profile, tying in packers, etc.) during testing well 4.
  1. Well test operations while testing well 4.
  1. Well stimulation via bottomhole zone treatment (by chemicals).

4.   Well suspension (abandonment) upon termination of testing operations on well 4.

5.   Geophysical survey, perforating and blasting operations (including openhole logging, perforation, fluid movement profile, injection profile, tying in packers, etc.) are planned while drilling well 7.

6.   Well test operations while drilling and testing well 7.

7.     Well stimulation via bottomhole zone treatment (by chemicals).

8.   Pilot production in case of commercial inflow of hydrocarbons.

Findings:

The main result of testing well 4 of Yelley-Igaiskaya area is obtaining commercial inflow of gas, as well as inflow of liquid hydrocarbons represented by condensate from the weathered crust of Paleozoic (2990-3000 m).

Results of testing 6 objects of core Paleozoic demonstrating presence of gas, as well as detailed description of technological operations, are stated in acts of testing objects 1-6, act of testing object 7 is being prepared at the moment.

Key points of testing should be mentioned briefly. When performing acid treatment, gas showings were observed in all the tested objects from zones treated with acid directly proportional to volume of agent pumped in. When joint testing of the second and the third object intervals during flow enhancement through pressurizing up to 320 ATM, excess pressure growth was observed in tubing up to 50 and 20 ATM accompanied by generation of gas cap.   When joint testing of object intervals 10, 11, and 12 after acid treatment fluid overflow through tubing was observed. The overflow was accompanied by gas showings (the gas was flammable). The well produced to the flare pit through 5 and 3 mm chokes. Initial overflow rate made 0,83 m3/hour. In five hours and 45 minutes the overflow stopped. Total volume of fluid produced from the well (by overflowing) ~ 2m3.

It should be mentioned that while drilling the well, most fractured and permeable intervals, most probably, absorbed big amounts of drilling mud, which, in its turn, reduced by times or even to zero, filtration capacity of oil and gas bearing zones. The depth of drilling mud invasion is difficult to evaluate. In order to reduce drilling mud effect (skin-effect reduction), as well as improve reservoir connectivity, hydraulic fracturing with filling fractures with proppant is recommended.

When testing object 6 comprising two prospective intervals (3028-3060 m, 3090-3093 m), in December 2014 – January 2015 overflow of technical water was received after perforation job and reduction of swabbing level till depth of 600 m, and the well started cleaning. Because of proximity to hazardous object (weathered crust of Paleozoic) the decision was made to identify injectivity profile in perforation interval in order to identify chances of killing the well in case of receiving abnormally high wellhead pressures (300-350 ATM). According to current field information, two gas discharging intervals were identified (3028-3060 m, 3090-3093 m), as well as one intaking interval (3040-3046 m), characterized by really high flow properties. Injectivity of intaking interval according to the results of field geophysical test, is about 230 m3/day. In such a way, for the first time since the starting moment of testing well 4 of Yelley-Igaiskaya area a reservoir was found in Paleozoic deposits having high flow properties.

On 11.02.2015 commercial inflow of hydrocarbons was received while testing object 7 from deposits of weathered crust of Paleozoic (perforation interval 2990-3000 m).

On 14.02.2015 the flowrate of gas condensate mixture made 114 thousand m3 while the well was producing through a 12 mm choke.

During producing the well through orifice gauge of critical flow with 12-16 mm chokes with the purpose of flushing the bottomhole zone from solids, intense recovery of solids, presumably, reservoir rock debris from near wellbore zone was observed, which makes it possible to draw the conclusion about the presence of a reservoir which is characterized by absolute permeability of more than a 100 mD (0,1 microns), which is also confirmed by absence of core while drilling.

After killing the well, as a result of well reverse circulation 60 liters of cuttings were recovered on surface from the near wellbore zone (rounded cuttings of rocks constituting weathered crust, cuttings of the cement rock, etc. up to 28 mm in size). This fact can also serve as justification of presence of a highly permeable thickness. The debris recovered were sent for laboratory analysis with the purpose of identifying the age of rocks and their mineral composition.

Well test was carried out, 4 well operating modes were tested at different chokes, pressure buildup, samples of gas, stable condensate and associate water were taken. Laboratory analysis of associate water was carried out. Condensate samples were sent for laboratory analysis.

Detailed description of technological operations when testing object 7 will comprise act for testing object 7 which is currently is at the stage of being prepared.

Based on the information received, such as re-processing and reinterpretation of seismic data which were obtained in past years and geophysical survey data taken from appraisal and stratigraphic wells drilled in past years, as well as well test data of well 4, receiving commercial inflow of hydrocarbons in well 4 from object 7 (interval of 2990-3000 m, weathered crust), reservoir fluids sample analysis (separator gas, condensate, reservoir water), the company possesses enough data in order to prepare Current estimation of hydrocarbon reserves of Yelley-Igaiskaya area in categories of С1 + С2 according to Russian reserves classification followed by receiving Field Discovery Certificate.

(See table in enclosed pdf)

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