6.3. Katangli deposit.

Katangli deposit is located in the Northern part of the Sakhalin region, it was discovered in 1928, the operation began in 1929 [19].

In regard to tectonic, Katangliyskiy anticlinal fold is dedicated to Nogliko- Katangliyskiy anticlinal zone. The fold is complicated by faulting. There are determined three basic blocks that are broken into smaller blocks by the breaks system.

There is installed the oil content of the I, II, III reservoirs of Daginskiy Suite (middle Miocene). In general, there are revealed 13 pure oil deposits.

Productive strata of the deposit Katangli occur at the depths of 30-240 meters. They are composed mainly of friable rocks - sands and siltstones, sometimes containing interlayer more cemented clay siltstones and sandstones and thin interlayers of clays. Oil composition belongs to heavy, tarry, low-sulfur, low paraffin. The viscosity of oil in situ is 300 - 900 MPa*s.

Until 1969 the mine was developed by means of natural drives, further, the application of thermal methods have been started.

As at 1.01.2008, the operating well stock consists of 285 of producing and 81 injection wells. The current oil production rate is equal to 1.6 t/day, liquid production rate is 16.5 t/day. The current share of water in the output is 90.4 %. During 2007it has been recovered 153,1 thousand tons of oil and 1596,9 thousand tons of liquid from the deposit. The accumulated oil withdrawal is 5896 thousand tons from the beginning of the development, including 2476 thousand tons from the beginning of the stimulation process by thermal methods, figure 6.1. Current ORF equals 0.317 when the approved one is 0,483 (category B+C1), a selection from the initial recoverable reserves is 65,6 %.

In 2007 there was injected 717,5 thousand tones of steam and 972,9 thousand m³ of water to the reservoir at 75 operating wells, including 40 steam-injected and 35 water-supply wells. Average well intake capacity by steam is 54 t/day, by water 84 m³/day. Cumulative steam-oil ratio is 4.1 t/t

The cumulative injection from the beginning of the development consists of: 11720 thousand tones of steam, 5939 thousand m³ of water.

Fig.6.1. Current oil production rate changes in dependence on steam injection.

Since 2009 in Katangli deposit it is provided the wells operation with horizontal end with the use of steam injection into the reservoir. It is projected to increase oil output in 7 times in comparison with the vertical wells [19].

6.4. Canada high-viscosity oil deposits.

Canada is a country with the most high-viscosity oil reserves (HVO) and hydrocarbon raw materials of bituminous minerals (HRMBM). Geological reserves are estimated as 51 billion tons where 4.2 billion tons can be considered as proven and probable [19].

Extra high-viscosity oil and bitumen are extracted mainly in the fields of Alberta province at the depths of 60...750 m where the viscosity of oil in tar sands reaches tens of thousands mPa*s

The development is carried out on the natural drives, by means of cold heavy oil production with sand (CHOPS), (it gives up to 20 % of oil production).To enhance the oil recovery there were applied thermal methods: in-situ combustion; steam assisted gravity drainage (SAGD); cyclic steam stimulation (CSS)

There are developed and tested simultaneously the following production methods on the bitumen deposits:

- Open-pit method is used on two main cross-sections, belonging to the companies, united in "San-Cor Inc." and "Syncrude Limited";

- Mining method is used with the further implementation of reservoir steam stimulation (through the system of drilling from system wells drifts);

- Borehole method considers the drilling of horizontal wells from the surface within the productive formation and vertical wells;

- Combined method considers the drilling of a big diameter borehole from the surface (in the lower part up to 7.6 m), and then there is drilled a set of horizontal wells within the reservoir from the chamber.

The Athabasca deposit is located in Western Canada, in the province of Alberta. Industrial production has begun since the mid-20th of the last century. The main concentration of heavy oil is situated in 3 layers: the Lower Cretaceous McMurray, Wabiskaw and Grand Rapids, the reserves are estimated in 218 billion. m3. The formations occur at the depth from 0 to 500 M. The sands of oil-bearing formations are not sealed, have good permeability from 3 to 12 D, porosity varies from 28%to 35%, net oil pay thickness reaches 75 m, viscosity 200 000 mPa*s. The formations that are at the depth from 0 to 50 m are economically suitable to develop by open-pit method; the achieved ORF is from 60 to 85%. For the reservoirs that bed at the depths greater than 59 m the thermal methods are more appropriate, the achieved ORF is from 30 to 50%. Average daily oil production rate is around 128 000 m³/day.

The Christina Lake deposit is located in the North-East of the Alberta province. The reserves are estimated in 3 mlds. m³, the recoverable reserves are estimated in 600 million m³, oil-saturated thickness reaches 20 m, viscosity reaches 100 000 mPa*s, porosity is 30-35%., permeability is from 3 to 10 D. The basic development method, as well as the future of this field is set on steam-assisted gravity drainage technology SAGD.

The Cold Lake deposit is located in Central-Eastern part of the province of Alberta. Oil was discovered in 1890, industrial development has started since the 1960s. The reserves are estimated in 30 mlds.m³. The main reserves are concentrated in the layers: Clearwater, Grand Rapids, McMurray/Wabiskaw. Permeability varies from 2 to 5 D, porosity is from 30 to 40%, the viscosity is 200 000 mPa*s, oil-saturated thickness reaches 40m. The development on the natural drives didn’t give the expected results, the achieved ORF was not more than 5%. Among thermal methods the most efficient were CSS with ORF - 25% and SAGD ORF - 50%.

The Grosmont deposit is located in the province of Alberta. The reserves are estimated in 43 million tons. The depth of oil reservoirs is up to 200m. Net oil pay thickness reaches 40 m., porosity is 20%permeability varies from 10 to 100 mD, viscosity is up to 1 600 000 mPa*s. The main way of the deposit development is on natural drives. Cyclic steam stimulation (CSS) has shown good results.

The Hahgingstone deposit was opened in 1970. The main productive formation is McMurray. From 1979 to 1983 there were conducted the experimental works - electric reservoir heating. From 1983 to 1992 there was carried out cyclic steam injection. Since 1997 there has been begun the stage realization of SAGD.

The Linbergh deposit is located in the East-Central part of Alberta at the distance of 80km from it. There were drilled about 1500 wells. The development is usually carried out by natural drives, the technology CHOPS is used. Also, cyclic steam stimulation is implemented. Table 6.1 gives the geological-physical characteristics of the reservoir.

Table 6.1.

Parameters	Meanings
Average formation thickness, m	9
Average depth to the upper boundary, m	600
Porosity, %	30.7
Oil density, kg/cm3	980
Permeability, mD	1500
Original formation pressure, MPa	3.4
Original formation temperature, 0С	25
Viscosity in formation conditions, mPa*s	8000
Initial producing gas-oil ratio, m3/m3	8.9

The Frog Lake deposit is located in 240 km. to the East of Edmonton city and 80 km to the North-West of the province of Alberta on the border of the province of Saskatchewan. Table 1.2 shows the geophysical characteristics of the reservoirs. The deposit was discovered in 1959. The development was carried out on natural drives, from 1965 to 1968. There were conducted experimental works, connected with steam injection into oil reservoirs Dina, McLaren, and Lover Waseca. These tests showed good results. Since 1993 there have been operated horizontal wells on natural drives that also has showed high efficiency.

Table 6.2.

Object	McLaren	Upper Waseca	Lower Waseca	Sparky	Dina
Oil saturation, %	80	75	80	75	80
Porosity, %	32	33	33	32	30
Formation temperature, 0С	20	20	20	22	24
Reservoir pressure, MPa	2.8	2.8	2.8	2.8	3.5
Permeability, D	1-2	1-2	2-4	2-4	3-5
Oil viscosity at 20 0С, MPa*s	25000	25000	25000	20000	50000
Depth, m	415-470	440-485	455-490	455-500	540-590

The Cactus Lake deposit is located in the province of Saskatchewan to the East of the province of Alberta, in 110 km from to the South of Leodminster. Production is carried out from the powerful, not consolidated fluvial deposits with total thickness from 22 to 30 m., 60-90% of which are effective oil-saturated thickness. The main reservoir is McLaren, permeability is 2-5 D, the average oil saturation is 85%, the viscosity is 5,000 mPa*s. The development was carried out by natural drive and with the help of CHOPS technology. The wells were drilled both vertical and horizontal. The length of the horizontal parts of the wells was from 1000 to 1200 m, the distance between the wells was about 200m.