Petro Kamchatka

Exploration History

The onshore West Kamchatka Basin was explored in the Soviet era with a large number of shallow wells drilled in the 1930s and 1940s. A few deep wells, based on surface geology, were drilled from the 1950s until the early 1980s. This effort resulted in a number of natural gas discoveries at Kolpakovsky which have a combined reserves estimated at 685 Bcf. Very little useable seismic was acquired in this era of exploration.

Source

Recent advances in geochemical fingerprinting have enabled recognition of coal sourced oil in many basins worldwide (NW Java; Turpan-Hami, China; Gippsland, Australia; etc.). PetroKamchatka’s studies show West Kamchatka coals to be very similar to the Talang Akar source coals of NW Java.

 

PetroKamchatka has examined a number of coal sourced oil controls. As far as the depositional environment is concerned, indications are of swamps with high bacterial activity and low drainage. In addition, the composition of materials, a high hydrogen content, and expulsion efficiency studies (these coals expel at 10-50% oil saturation) all indicate a working system.

Overall, PetroKamchatka believes that mature oil prone source rocks exist in West Kamchatka, and within its lands. There is significant evidence of expelled oil from previous drilling. Our geological work further indicates that source kitchens are expected to have generated and expelled large volumes of coal derived oil, and that a deep oil source may also exist. PetroKamchatka believes that the available data and analyses represent a strong case for the overlooked oil discovery potential of this basin.

Reservoir Rocks

PetroKamchatka has undertaken extensive geological field work on surface outcrops in West Kamchatka, from 2002 - 2008. This work was undertaken to better understand the regional and local stratigraphy and the structure of our licences and to prove the reservoir potential of the West Kamchatka basin.

Primary targets are the Paleocene-Eocene lithic sandstones of the Napanskaya–Snatolskaya succession with 80-160m of net sand thickness. Effective reservoir is more difficult to estimate but is believed to range from 10-100 metres across the area. The Soviet era drilling information lacks porosity logs but there is evidence of porous and permeable sandstones on the old SP logs with up to 29 metres indicated at Tigil and 42 metres at Icha.

Stratigraphic Framework

The Miocene to Paleocene stratigraphy has been studied by PetroKamchatka over several summers of field work within the Tigil licence, and adjacent, areas. Data from these studies is summarized in the stratigraphic column shown on the right. Formation names, ages, lithologies, depositional environments and position of unconformity surfaces are shown. The global eustatic sea level curve is schematically illustrated on the left and the position and ages of related first order sequence boundaries are shown. Unconformities defined in Tigil outcrop studies appear to coincide with global sequence boundaries which suggests that these unconformities are not simply local tectonic induced surfaces; rather, they will be regionally correlatable, so that sequence stratigraphic and system tract fundamentals will have utility when defining reservoir distribution concepts.

Primary Reservoir Target

The Paleocene to Middle Eocene Napanskaya and Snatolskaya formations are the primary reservoir targets. The location of measured sections, the amount of sand and total formation thicknesses are shown below.

These formations can be up to a 1,000 m in thickness and on average contain 25% sand. The Napanskaya comprises approximately four stacked cycles of dominatingly alluvial to fluvial conglomerates and sands and is interpreted to have been deposited with a low stand system tract. The Snatolskaya contains three cycles of fluvial conglomerates and sand separated by thin shallow marine shale prone transgressions. This stacking pattern suggests a low stand to transgressive depositional setting.

Preliminary observations suggest that these sands are arenites with a lithic component which raises concerns about the preservation of reservoir quality in the subsurface. Ongoing petrographic work is being conducted to properly evaluate this risk element: Moreover, our first exploration well at Prospect AB in Tigil (Oyarskaya 1P), is catering for such risk by careful selection of the drilling mud.

Secondary Reservoir

PetroKamchatka has identified two potential secondary reservoir zones for the Tigil licence, including the high stand shoreline sands of the Kuluvenkskaya Formation, and the low stand to transgressive conglomerates and sand of the Illinskaya Formation.

Sequence stratigraphic concepts also suggest the possibility of an additional reservoir target existing. At Kolpakovksy south of the Icha block, the gas bearing reservoirs are called Snatolskaya but biostratigrahic data indicates that these sands are immediately over laid by late Oligocene-Miocene sediment.

How this stratigraphic juxtaposition can occur is difficult to understand without incorporating a major subunconformity erosion or hiatus. It is more likely that the assigned Eocene age results from reworked sediment and that these reservoirs are low stand deposits which rest on the Late Oligocene unconformity. Though sands of this age are not exposed in Tigil the unconformity is recognized both in outcrop and on seismic creating the possibility that low stand reservoir sands may exist in the subsurface. Seismic stratigraphic interpretation is currently endeavoring to identify and map this reservoir interval.

PetroKamchatka has successfully executed five seismic programs covering 1,306 km over the course of four years. Seismic operations have been a major undertaking for PetroKamchatka and have ultimately led to the identification of 13 prospects and the current drilling locations at Oyarskaya 1P and Prospect E on the Tigil Block.

The seismic acquired by PetroKamchatka has been a fundamental input for the exploration work carried out on the Tigil and Icha blocks. The existing wells on the licences, drilled during Soviet times, enabled only limited analysis. The seismic programs also helped PetroKamchatka to better understand why previous (Soviet era) drilling had limited success.

Interpretation of acquired seismic in conjunction with field work has led to the establishment of a stratigraphic framework, which plays a major role in correlating events on seismic and defining relative timing of structural events. Seismic analysis has also led to the identification of three structural play types which classifies prospects and leads. This classification has had a direct impact on the selection of drilling locations.

 

The Oyarskaya #1 well in Prospect A/B on the Tigil Block was spudded on October 22, 2009. On January 13, 2010, the well reached a depth 3,236 metres without encounering the target tertiary sands and was subsequently abandoned.

The Chernorechenskaya #1 well in Prospect E on the Tigil Block was spudded on April 15, 2010.  On May 31, 2010, the well reached a depth 2,596 metres without encountering the target tertiary sands and was subsequently abandoned.

The Company is currently evaluating future dirlling prospects.