PetroNeft reports drilling results at Cheremshanskoye field, Russia

November 08, 2018

DUBLIN -- PetroNeft--an oil and gas E&P company operating in the Tomsk Oblast, Russian Federation, and 50% owner and operator of Licenses 61 and 67--has announced that cased-hole testing of the J1-1 and J1-3 intervals of the Cheremshanskoye No.4 (C-4) well in Licence 67 has confirmed the excellent results from the open-hole testing reported on Aug. 28.

Highlights:

  • Excellent results of open-hole testing confirmed and upgraded by extensive cased-hole test of the J1-1 and J1-3 intervals. The well productivity from the cased-hole test indicates that the combined intervals should achieve in excess of 450 bopd when produced on an electric submersible pump.
  • The C-4 well proves up the northern half of the Cheremshanskoye field with oil tested from two horizons.
  • The well is the first one drilled with the help of 3D seismic data acquired by PetroNeft in 2014 and is approximately 5km from two previous oil wells which were drilled along the southern boundary of the field (C-1 & C-3 wells).
  • Result has the potential to increase gross reserves by 40 MMbbl (20 MMbbl net to PetroNeft).

Licence 67

The C-4 well is located on the northern half of Cheremshanskoye field in License 67. The aim of the well was to prove up the northern extent of the field based on the 3D seismic data. The well was being drilled under the joint venture agreement with our partner for Licence 67, Arawak Energy on a 50:50 basis. The well spudded on Aug. 2 and results of the open-hole testing were reported on Sept. 28. An extensive cased-hole testing program has since been conducted for the J1-1 and J1-3 intervals.

Cased-hole test no. 1 of the J1-3 interval was conducted on the perforated interval from 2,644-2,655 m MD. The interval was step tested on different choke sizes and pressure regimes. The final natural oil flow rate on a 3-mm choke was 11.1 m3/day (70 bopd). The productivity index is calculated at 0.22 m3/day/atm, which translates to about 277 bopd at 200 atm drawdown (typical drawdown expected for an electrical submersible pump).

The company then isolated the J1-3 interval from the J1-1 interval and conducted cased-hole test no. 2. The J1-1 interval was perforated from 2,631 to 2,634 m MD. The interval was step tested at different choke sizes and pressure regimes. The final test on a 5-mm choke had a natural oil flowrate of 17.4 m3/day (109 bopd). The productivity index is calculated at 0.15 m3/day/atm which translates to about 189 bopd at 200 atm drawdown.

Assuming the well is completed with just an electrical submersible pump, it is expected that the combined flowrate of the two intervals to be in excess of 450 bopd. This compares to the combined open-hole prorated test result of 399 bpd.

The two cased-hole tests combined with the log and core data in the Upper Jurassic reportedly are very encouraging. There are currently no reserves booked for the Upper Jurassic at Cheremshanskoye and is the company's estimate that there could be about 40 MMbbl of proven and probable reserves in the Upper Jurassic at Cheremshanskoye, based on these results (20 MMbbl net to PetroNeft).

The company is in the process of getting the reserves approved by the State Reserve Committee (GKZ) and reviewing the options for producing the C-4 well on long-term test production this winter, when the oil can be trucked on winter roads.

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