Work in the southern part of the Priobskoye field. Priobskoye oil field - iv_g

Now LLC RN-Yuganskneftegaz is steadily working on the development of the northern part of the Priobskoye oil field, and the development of the southern segment of the field is being carried out by Gazpromneft-Khantos LLC, which belongs to the Gazpromneft company. The southern segment of the Priobskoye oil field has small licensed areas. Since 2008, the development of the Sredne-Shapshinsky and Verkhne-Shapshinsky segments has been carried out by NAC AKI OTYR, which belongs to OJSC Russneft.

Prospects for Priobsky NM

A year ago, the Gazpromneft-Khantos company became the owner of a license to conduct geological research of parameters related to deep oil-saturated horizons. The southern part of the Priobskoye oil deposit, including the Bazhenov and Achimov formations, is subject to research.

Last year was marked by the analysis of geographic data on the territory of the Bazheno-Abalak complex of the South Priobsky oil field. A set of specialized core analysis and assessment of this class of reserves involves the procedure of drilling four exploration and appraisal wells with an inclined direction.

Horizontal wells will be drilled in 2016. To estimate the volume of recoverable reserves, multi-stage hydraulic fracturing is planned.

Impact of the deposit on the ecology of the area

The main factors influencing the environmental situation in the field area are the presence of emissions into the atmosphere layers. These emissions include petroleum gas, oil combustion products, and components of evaporation from light hydrocarbon fractions. In addition, spills of oil products and components onto the soil are observed.

The unique territorial feature of the deposit is due to its location on floodplain river landscapes and within the water protection zone. Making specific development requirements is based on high value. In this situation, floodplain lands are considered, with characteristic high dynamism and complex hydrological regime. This territory is chosen for nesting by migratory birds of semi-aquatic species, many of which are included in the Red Book. The deposit is located on the territory of migration routes and wintering grounds for many rare representatives of ichthyofauna.

Even 20 years ago, the Central Commission for the Development of NM and GPS under the Ministry of Fuel and Energy of Russia, as well as the Ministry of Environmental Protection and Natural Resources of Russia, approved the exact scheme for the development of the Priobskoye NM and the environmental part of all preliminary design documentation.

The Priobskoye deposit is cut into two parts by the Ob River. It is swampy and during a flood, most of it is flooded. It was precisely these conditions that contributed to the formation of fish spawning grounds on the territory of the NM. The Ministry of Fuel and Energy of Russia presented materials to the State Duma, on the basis of which it was concluded that the development of the Priobskoye oil pipeline is complicated due to existing natural factors. Such documents confirm the need for additional financial resources in order to use only the latest and environmentally friendly technologies on the territory of the field, which will allow highly efficient implementation of environmental protection measures.

The Priobskoye oil and gas field is geographically located on the territory of the Khanty-Mansiysk Autonomous Okrug of the Tyumen Region of the Russian Federation. The closest city to the Priobskoye field is Nefteyugansk (located 200 km east of the field).

The Priobskoye field was discovered in 1982. The field is characterized as multi-layer, low-productivity. The territory is cut by the Ob River, swampy and during flood periods it is mostly flooded; Here are the spawning grounds for fish. As noted in the materials of the Ministry of Fuel and Energy of the Russian Federation presented to the State Duma, these factors complicate the development and require significant financial resources to apply the latest highly efficient and environmentally friendly technologies.

The license for the development of the Priobskoye field belongs to a subsidiary of Rosneft OJSC, the Rosneft-Yuganskneftegaz company.

According to experts, the development of the field under the existing taxation system is unprofitable and impossible. Under the terms of the PSA, oil production over 20 years will amount to 274.3 million tons, state income - $48.7 billion.

Recoverable reserves of the Priobskoye field are 578 million tons of oil, gas - 37 billion cubic meters. The development period under the terms of the PSA is 58 years. Peak production level - 19.9 million. tons in the 16th year of development. The initial financing was planned to be $1.3 billion. Capital costs - $28 billion, operating costs - $27.28 billion. Probable directions for transporting oil from the field are Ventspils, Novorossiysk, Odessa, Druzhba.

Yugansneftegaz and Amoso ​​began discussing the possibility of joint development of the northern part of the Priobskoye field in 1991. In 1993, Amoso ​​took part in an international tender for the right to use subsoil in the fields of the Khanty-Mansi Autonomous Okrug and was recognized as the winner of the competition for the exclusive right to become a foreign partner in the development of the Priobskoye field together with Yuganskneftegaz.

In 1994, Yuganskneftegaz and Amoso ​​prepared and submitted to the government a draft production sharing agreement and a Tenico-economic and environmental feasibility study for the project.

In early 1995, a further feasibility study was submitted to the government, which was amended later that year in light of new data obtained about the field.
In 1995, the Central Commission for the Development of Oil and Oil and Gas Fields of the Ministry of Fuel and Energy of the Russian Federation and the Ministry of Environmental Protection and Natural Resources of the Russian Federation approved a revised scheme for the development of the field and the environmental part of the pre-project documentation.

On March 7, 1995, then-Prime Minister Viktor Chernomyrdin issued an order to form a government delegation of representatives of the Khanty-Mansi Autonomous Okrug and a number of ministries and departments to negotiate a PSA for the development of the northern part of the Priobskoye field.

In July 1996, in Moscow, a joint Russian-American commission on economic and technical cooperation issued a joint statement on the priority of projects in the energy field, among which the Priobskoye field was specifically named. The joint statement indicated that both governments welcome commitments to conclude a production sharing agreement for this project by the next commission meeting in February 1997.

At the end of 1998, Yuganskneftegaz's partner in the Priobskoye field development project, the American company Amoso, was absorbed by the British company British Petroleum.

At the beginning of 1999, BP/Amoso ​​officially announced its withdrawal from participation in the Priobskoye field development project.

Ethnic history of the Priobskoye deposit

Since ancient times, the area of ​​the deposit was inhabited by the Khanty. The Khanty developed complex social systems called principalities and by the 11th-12th centuries. they had large tribal settlements with fortified capitals, which were ruled by princes and defended by professional troops.

The first known contacts of Russia with this territory took place in the 10th or 11th century. At this time, trade relations began to develop between the Russians and the indigenous population of Western Siberia, which brought cultural changes to the lives of the aborigines. Iron and ceramic household utensils and fabrics appeared and became a material part of the life of the Khanty. The fur trade became extremely important as a means of obtaining these goods.

In 1581, Western Siberia was annexed to Russia. The princes were replaced by the tsarist government, and taxes were paid into the Russian treasury. In the 17th century, tsarist officials and service people (Cossacks) began to settle in this territory and contacts between Russians and Khanty developed further. As a result of closer contacts, Russians and Khanty began to adopt the attributes of each other’s ways of life. The Khanty began to use guns and traps, and some, following the example of the Russians, began breeding cattle and horses. The Russians borrowed some hunting and fishing techniques from the Khanty. The Russians acquired land and fishing grounds from the Khanty, and by the 18th century most of the Khanty land was sold to Russian settlers. Russian cultural influence expanded in the early 18th century with the introduction of Christianity. At the same time, the number of Russians continued to increase and by the end of the 18th century, the Russian population in this area outnumbered the Khanty five times. Most Khanty families adopted farming, livestock breeding and gardening from the Russians.

The assimilation of the Khanty into Russian culture accelerated with the establishment of Soviet power in 1920. The Soviet policy of social integration brought a unified education system to the region. Khanty children were usually sent from their families to boarding schools for a period of 8 to 10 years. Many of them, after graduating from school, could no longer return to the traditional way of life, not having the necessary skills for this.

Collectivization, which began in the 1920s, had a significant impact on the ethnographic character of the territory. In the 50-60s, the formation of large collective farms began and several small settlements disappeared as the population united into larger settlements. By the 50s, mixed marriages between Russians and Khanty became widespread, and almost all Khanty born after the 50s were born in mixed marriages. Since the 60s, as Russians, Ukrainians, Belarusians, Moldovans, Chuvash, Bashkirs, Avars and representatives of other nationalities migrated to the region, the percentage of Khanty decreased even more. Currently, the Khanty make up a little less than 1 percent of the population of Khanty-Mansi Autonomous Okrug.

In addition to the Khanty, the territory of the Priobskoye field is inhabited by Mansi (33%), Nenets (6%) and Selkups (less than 1%).

The Priobskoye field appeared on the map of the Khanty-Mansi Autonomous Okrug in 1985, when its left bank part was discovered with well number 181. Geologists received a gush of oil with a volume of 58 cubic meters per day. Four years later, drilling began on the left bank, and commercial operation of the first well on the right bank of the river began 10 years later.

Priobskoye field characteristics

The Priobskoye field lies close to the borders of the oil and gas bearing regions of Salymsky and Lyaminsky.

The characteristics of the oil from the Priobskoye field make it possible to classify it as low-resin (paraffins at the level of 2.4-2.5 percent), but at the same time with a high sulfur content (1.2-1.3 percent), which requires additional purification and reduces profitability. The viscosity of reservoir oil is at the level of 1.4-1.6 mPa*s, and the thickness of the layers reaches from 2 to 40 meters.

The Priobskoye field, whose characteristics are unique, has geologically justified reserves of five billion tons. Of these, 2.4 billion are classified as proven and recoverable. As of 2013, the estimate of recoverable reserves at the Priobskoye field was over 820 million tons.

By 2005, daily production reached high figures - 60.2 thousand tons per day. In 2007, over 40 million tons were produced.

To date, about a thousand production wells and almost 400 injection wells have been drilled at the field. The reservoir deposits of the Priobskoye oil field are located at a depth of 2,3,2,6 kilometers.

In 2007, the annual production of liquid hydrocarbons at the Priobskoye field reached 33.6 million tons (or more than 7% of all production in Russia).

Priobskoye oil field: development features

The peculiarity of drilling is that the bushes of the Priobskoye field are located on both sides of the Ob River and most of them are located in the river floodplain. On this basis, the Priobskoye deposit is divided into South- and North-Priobskoye. In the spring and autumn, the field area is regularly flooded with flood waters.

This arrangement is the reason that its parts have different owners.

On the northern bank of the river, development is carried out by Yuganskneftegaz (a structure that passed to Rosneft after YUKOS), and on the southern bank there are areas that are being developed by the Khantos company, a structure of Gazprom Neft (in addition to Priobsky, it is also involved in the Palyanovsky project). In the southern part of the Priobskoye field, Russneft’s subsidiary, the Aki Otyr company, has been allocated small license areas for the Verkhne- and Sredne-Shapshinsky areas.

These factors, along with the complex geological structure (multiple layers and low productivity), make it possible to characterize the Priobskoye field as difficult to access.

But modern hydraulic fracturing technologies, by pumping large amounts of water mixture underground, can overcome this difficulty. Therefore, all newly drilled pads of the Priobskoye field begin to be exploited only with hydraulic fracturing, which significantly reduces operating costs and capital investments.

In this case, three oil layers are fracturing simultaneously. In addition, the main part of the wells is laid using the progressive cluster method, when lateral wells are directed at different angles. In cross-section, it resembles a bush with branches pointing downwards. This method saves on the arrangement of surface drilling sites.

The cluster drilling technique has become widespread because it allows preserving the fertile soil layer and only has a minor impact on the environment.

Priobskoye field on the map

The Priobskoye field on the map of Khanty-Mansi Autonomous Okrug is determined using the following coordinates:

• 61°20′00″ north latitude,
• 70°18′50″E.

The Priobskoye oil field is located just 65 km from the capital of the Autonomous Okrug - Khanty-Mansiysk and 200 kilometers from the city of Nefteyugansk. In the field development area there are areas with settlements of indigenous small nations:

• Khanty (about half the population),
• Nenets,
• Muncie,
• Selkups.

Several natural reserves have been formed in the area, including Elizarovsky (republican significance), Vaspukholsky, and Shapshinsky cedar forest. Since 2008, in the Khanty-Mansi Autonomous Okrug - Yugra (the historical name of the area with its center in Samarovo), a natural monument “Lugovskie Mammoths” was established with an area of ​​161.2 hectares, on the site of which fossil remains of mammoths and hunting tools dating back from 10 to 15 thousand years were repeatedly found back.

Priobskoye oil field

§1. Priobskoye oil field.

Priobskoe- the largest field in Western Siberia is administratively located in the Khanty-Mansiysk region at a distance of 65 km from Khanty-Mansiysk and 200 km from Nefteyugansk. Divided by the Ob River into two parts - left and right banks. Development of the left bank began in 1988, the right - in 1999. Geological reserves are estimated at 5 billion tons. Proven and recoverable reserves are estimated at 2.4 billion tons. Opened in 1982. Deposits at a depth of 2.3-2.6 km. Oil density 863-868 kg/m3 (medium oil type, as it falls in the range 851-885 kg/m3), moderate paraffin content (2.4-2.5%) and sulfur content 1.2-1 .3% (belongs to the sulfur class, class 2 oil supplied to refineries in accordance with GOST 9965-76). As of the end of 2005, there are 954 production and 376 injection wells in the field. Oil production at the Priobskoye field in 2007 amounted to 40.2 million tons, of which Rosneft - 32.77, and Gazprom Neft - 7.43 million tons. The trace element composition of oil is an important characteristic of this type of raw material and carries various geochemical information about the age of the oil, conditions of formation, origin and migration routes and is widely used for identifying oil fields, optimizing the field search strategy, and separating the products of jointly operated wells.

Table 1. Range and average content of microelements in Priobsk oil (mg/kg)

The initial flow rate of existing oil wells is from 35 tons/day. up to 180 t/day. The location of the wells is clustered. Oil recovery factor 0.35.

A well cluster is a location where the wellheads are located close to each other on the same technological site, and the bottoms of the wells are located at the nodes of the reservoir development grid.

Currently, most production wells are drilled using the cluster method. This is explained by the fact that cluster drilling of fields can significantly reduce the size of the areas occupied by drilling and then production wells, roads, power lines, and pipelines.

This advantage is of particular importance during the construction and operation of wells on fertile lands, in nature reserves, in the tundra, where the disturbed surface layer of the earth is restored after several decades, in swampy areas, which complicate and greatly increase the cost of construction and installation work of drilling and operational facilities. Cluster drilling is also necessary when it is necessary to discover oil deposits under industrial and civil structures, under the bottom of rivers and lakes, under the shelf zone from the shore and overpasses. A special place is occupied by cluster construction of wells in the Tyumen, Tomsk and other regions of Western Siberia, which made it possible to successfully construct oil and gas wells on backfill islands in a remote, swampy and populated region.

The location of wells in a cluster depends on the terrain conditions and the intended means of connecting the cluster to the base. Bushes that are not connected by permanent roads to the base are considered local. In some cases, bushes can be basic when they are located on transport routes. On local pads, wells are usually placed in a fan shape in all directions, which allows you to have the maximum number of wells on a pad.

Drilling and auxiliary equipment is mounted in such a way that when the rig moves from one well to another, the drilling pumps, receiving pits and part of the equipment for cleaning, chemical treatment and preparation of the drilling fluid remain stationary until the completion of the construction of all (or part) of the wells on this pad.

The number of wells in a cluster can vary from 2 to 20-30 or more. Moreover, the more wells in the cluster, the greater the deviation of the faces from the wellheads, the length of the trunks increases, the length of the trunks increases, which leads to an increase in the cost of drilling wells. In addition, there is a danger of trunks meeting. Therefore, there is a need to calculate the required number of wells in a cluster.

The deep pumping method of oil production is a method in which the liquid is lifted from the well to the surface using rod and rodless pumping units of various types.
At the Priobskoye field, electric centrifugal pumps are used - a rodless deep-well pump, consisting of a multi-stage (50-600 stages) centrifugal pump located vertically on a common shaft, an electric motor (an asynchronous electric motor filled with dielectric oil) and a protector that serves to protect the electric motor from liquid entering it. The motor is powered via an armored cable, lowered along with the pumping pipes. The rotation speed of the electric motor shaft is about 3000 rpm. The pump is controlled in the surface by a control station. The productivity of an electric centrifugal pump varies from 10 to 1000 m3 of liquid per day with an efficiency of 30-50%.

Electric centrifugal pump installation includes underground and surface equipment.
The installation of a downhole electric centrifugal pump (ESP) has only a control station with a power transformer on the well surface and is characterized by the presence of high voltage in the power cable, which is lowered into the well along with the tubing pipes. Electric centrifugal pump installations operate highly productive wells with high reservoir pressure.

The deposit is remote, difficult to access, 80% of the territory is located in the floodplain of the Ob River and is flooded during the flood period. The deposit is distinguished by a complex geological structure - a complex structure of sand bodies in area and section, the layers are hydrodynamically weakly connected. The reservoirs of productive formations are characterized by:

Low permeability;

Low sandiness;

Increased clay content;

High dissection.

The Priobskoye field is characterized by a complex structure of productive horizons both in area and in section. The reservoirs of horizons AC10 and AC11 are classified as medium and low productive, and AC12 are classified as abnormally low productive. The geological and physical characteristics of the productive strata of the field indicate the impossibility of developing the field without active influence on its productive strata and without the use of production intensification methods. This is confirmed by the experience of developing the operational section of the left bank part.

The main geological and physical characteristics of the Priobskoye field for assessing the applicability of various impact methods are:

1) depth of productive formations - 2400-2600 m,

2) the deposits are lithologically screened, the natural regime is elastic, closed,

3) the thickness of layers AS 10, AS 11 and AS 12, respectively, up to 20.6, 42.6 and 40.6 m.

4) initial reservoir pressure - 23.5-25 MPa,

5) reservoir temperature - 88-90°C,

6) low permeability of reservoirs, average values ​​according to the results

7) high lateral and vertical heterogeneity of layers,

8) viscosity of reservoir oil - 1.4-1.6 mPa*s,

9) oil saturation pressure 9-11 MPa,

10) naphthenic oil, paraffinic and low-resin.

Comparing the presented data with the known criteria for the effective use of reservoir stimulation methods, it can be noted that, even without a detailed analysis, the following methods for the Priobskoye field can be excluded from the methods listed above: thermal methods and polymer flooding (as a method of displacing oil from formations). Thermal methods are used for deposits with high-viscosity oils and at depths of up to 1500-1700 m. Polymer flooding is preferably used in formations with a permeability of more than 0.1 microns to displace oil with a viscosity of 10 to 100 mPa * s and at temperatures up to 90 ° C (for At higher temperatures, expensive polymers with special compositions are used).

The Priobskoye field is located in the central part of the West Siberian Plain. Administratively, it is located in the Khanty-Mansiysk region, 65 km east of Khanty-Mansiysk and 100 km west of the city. Nefteyugansk.

During the period 1978-1979 As a result of detailed seismic exploration of CDP, the Priobskoe uplift was identified. From this moment, a detailed study of the geological structure of the territory begins: the widespread development of seismic exploration in combination with deep drilling.

The discovery of the Priobskoye field took place in 1982 as a result of drilling and testing of well 151, when commercial inflow was obtained oil flow rate of 14.2 m 3 /day at a 4 mm choke from the intervals of 2885-2977 m (Tyumen formation YUS 2) and 2463-2467 m (formation AS 11 1) - 5.9 m 3 /day at a dynamic level of 1023 m.

Priob structure, according to the tectonic map of the Meso-Cenozoic platform cover.

The West Siberian geosyneclise is located in the junction zone of the Khanty-Mansi depression, the Lyaminsky megatrough, the Salym and West Lyaminsky groups of uplifts.

The first-order structures are complicated by swell-shaped and dome-shaped uplifts of the second order and individual local anticlinal structures, which are the objects of prospecting and exploration work on oil And gas.

The productive formations in the Priobskoye field are the formations of the "AS" group: AS 7, AS 9, AS 10, AS 11, AS 12. In stratigraphic terms, these layers belong to the Cretaceous deposits of the Upper Vartov Formation. Lithologically, the Upper Vartovskaya formation is composed of frequent and uneven interbedding of mudstones with sandstones and siltstones. The mudstones are dark gray, gray with a greenish tint, silty, micaceous. Sandstones and siltstones are gray, clayey, micaceous, fine-grained. Among the mudstones and sandstones there are interlayers of clayey limestones and siderite concretions.

The rocks contain charred plant detritus, rarely bivalves (inocerams) of poor and moderate preservation.

Permeable rocks of productive formations have a northeastern and submeridial strike. Almost all formations are characterized by an increase in the total effective thicknesses and sand content coefficient, mainly in the central parts of reservoir development zones, to increase reservoir properties and, accordingly, the strengthening of clastic material occurs in the eastern (for layers of the AC 12 horizon) and northeastern directions (for horizon AC 11).

Horizon AC 12 is a thick sandy body, elongated from southwest to northeast in the form of a wide strip with a maximum effective thickness in the central part of up to 42 m (well 237). In this horizon, three objects are distinguished: layers AC 12 3, AC 12 1-2, AC 12 0.

Deposits of the AC 12 3 formation are presented in the form of a chain of sandy lens-shaped bodies with a northeastern strike. Effective thicknesses vary from 0.4 m to 12.8 m, with higher values ​​confined to the main deposit.

The main deposit AS 12 3 was discovered at depths of -2620 and -2755 m and is lithologically screened on all sides. The dimensions of the deposit are 34 x 7.5 km, and the height is 126 m.

Deposit AS 12 3 in the area of ​​well. 241 was discovered at depths of -2640-2707 m and is confined to the Khanty-Mansi local uplift. The deposit is controlled from all sides by reservoir replacement zones. The dimensions of the deposit are 18 x 8.5 km, height - 76 m.

Deposit AS 12 3 in the area of ​​well. 234 was discovered at depths of 2632-2672 m and represents a lens of sandstones on the western dip of the Priob structure. The deposit dimensions are 8.5 x 4 km, and the height is 40 m, the type is lithologically screened.

Deposit AS 12 3 in the area of ​​well. 15-C was discovered at depths of 2664-2689 m within the Seliyarovsky structural ledge. The dimensions of the lithologically screened deposit are 11.5 x 5.5 km, and the height is 28 m.

The AS 12 1-2 deposit is the main one and is the largest in the field. It is confined to a monocline, complicated by local uplifts of small amplitude (region of wells 246, 400) with transition zones between them. It is limited on three sides by lithological screens and only in the south (towards the East Frolovskaya area) do reservoirs tend to develop. However, given the significant distances, the boundary of the deposit is still conditionally limited by a line running 2 km south of the well. 271 and 259. Oil-saturated thicknesses vary over a wide range from 0.8 m (well 407) to 40.6 m (well 237) tributaries oil up to 26 m 3 /day on a 6 mm fitting (well 235). The dimensions of the deposit are 45 x 25 km, height - 176 m.

Deposit AS 12 1-2 in the area of ​​well. 4-KhM was discovered at depths of 2659-2728 m and is confined to a sand lens on the northwestern slope of the Khanty-Mansiysk local uplift. Oil-saturated thicknesses vary from 0.4 to 1.2 m. The dimensions of the deposit are 7.5 x 7 km, height - 71 m.

Deposit AS 12 1-2 in the area of ​​well. 330 discovered at depths of 2734-2753m Oil-saturated thicknesses vary from 2.2 to 2.8 m. The dimensions of the deposit are 11 x 4.5 km, height - 9 m. Type - lithologically screened.

The deposits of the AC 12 0 formation - the main one - were discovered at depths of 2421-2533 m. It is a lens-shaped body oriented from southwest to northeast. Oil-saturated thicknesses vary from 0.6 (well 172) to 27 m (well 262). Tributaries oil up to 48m 3 /day on an 8 mm fitting. The dimensions of the lithologically screened deposit are 41 x 14 km, height - 187 m. AC 12 0 deposit in the area of ​​the well. 331 was discovered at depths of 2691-2713 m and represents a lens of sandy rocks. Oil-saturated the thickness in this well is 10 m. Dimensions 5 x 4.2 km, height - 21 m. Flow rate oil- 2.5 m 3 /day at Hd = 1932 m.

The AS 11 formation deposit is 2-4 lithologically screened type, there are 8 in total, opened by 1-2 wells. In terms of area, the deposits are located in the form of 2 chains of lenses in the eastern part (the most elevated) and in the west in the more submerged part of the monoclinal structure. Oil-saturated thicknesses in the east increase by 2 or more times compared to western wells. The total range of change is from 0.4 to 11 m.

The AS 11 2-4 formation deposit in the area of ​​well 246 was discovered at a depth of 2513-2555 m. The dimensions of the deposit are 7 x 4.6 km, height - 43 m.

Deposit of formation AS 11 2-4 in the area of ​​well. 247 was discovered at a depth of 2469-2490 m. The dimensions of the deposit are 5 x 4.2 km, height - 21 m.

Deposit of formation AS 11 2-4 in the area of ​​well. 251 was discovered at a depth of 2552-2613 m. The dimensions of the deposit are 7 x 3.6 km, height - 60 m.

Deposit of formation AS 11 2-4 in the area of ​​well. 232 was opened at a depth of 2532-2673 m. The dimensions of the deposit are 11.5 x 5 km, height - 140 m.

Deposit of formation AS 11 2-4 in the area of ​​well. 262 was opened at a depth of 2491-2501m. The dimensions of the deposit are 4.5 x 4 km, height - 10 m.

The AS 11 2-4 formation deposit in the area of ​​well 271 was discovered at a depth of 2550-2667 m. The dimensions of the deposit are 14 x 5 km.

Deposit of formation AS 11 2-4 in the area of ​​well. 151 were opened at a depth of 2464-2501m. The dimensions of the deposit are 5.1 x 3 km, height - 37 m.

Deposit of formation AS 11 2-4 in the area of ​​well. 293 was discovered at a depth of 2612-2652 m. The dimensions of the deposit are 6.2 x 3.6 km, height - 40 m.

The deposits of the AS 11 1 formation are confined mainly to the near-crest part in the form of a wide strip of north-eastern strike, limited on three sides by clay zones.

The main deposit AS 11 1 is the second largest within the Priobskoye field, discovered at depths of 2421-2533 m. On three sides the deposit is limited by clay zones, and in the south the border is drawn conditionally, along a line running 2 km south of well 271 and 259. Debits oil vary from 2.46 m 3 /day at a dynamic level of 1195 m (well 243) to 118 m 3 /day through an 8 mm fitting (well 246). Oil-saturated thicknesses vary from 0.4 m (well 172) to 41.6 (well 246). The dimensions of the deposit are 48 x 15 km, height up to 112 m, type - lithologically screened.

Deposits of the AS 11 0 formation. The AS 11 0 formation has a very small zone of development of reservoirs in the form of lens-shaped bodies, confined to the submerged areas of the near-crest part.

Deposit AS 11 0 in the area of ​​the well. 408 was opened at a depth of 2432-2501 m. The dimensions of the deposit are 10.8 x 5.5 km, height - 59 m, lithologically screened type. Debit oil from well 252 was 14.2 m3/day at Нд =1410 m.

Deposit AS 11 0 in the area of ​​the well. 172 was penetrated by one well at a depth of 2442-2446 m and has dimensions of 4.7 x 4.1 km, height - 3 m. Flow rate oil amounted to 4.8 m 3 /day at Hd = 1150 m.

Deposit AS 11 0 in the area of ​​the well. 461 measures 16 x 6 km. Oil-saturated thickness varies from 1.6 to 4.8 m. Type of deposit - lithologically screened. Debit oil from well 461 was 15.5 m 3 /day, Nd = 1145 m.

Deposit AS 11 0 in the area of ​​the well. 425 was penetrated by one well. Oil-saturated power - 3.6 m. Flow rate oil amounted to 6.1 m 3 /day at Нд =1260 m.

The AS 10 horizon was discovered within the central zone of the Priobskoye field, where it is confined to more submerged areas of the near-crest part, as well as to the southwestern wing of the structure. The division of the horizon into layers AS 10 1, AS 10 2-3 (in the central and eastern parts) and AS 10 2-3 (in the western) is to a certain extent arbitrary and is determined by the conditions of occurrence and formation of these deposits, taking into account the lithological composition of the rocks and the physical chemical characteristics oils.

The main deposit AS 10 2-3 was discovered at depths of 2427-2721 m and is located in the southern part of the field. Debits oil are in the range from 1.5 m 3 /day at an 8 mm fitting (well 181) to 10 m 3 /day at Nd = 1633 m (well 421). Oil-saturated thicknesses range from 0.8 m (well 180) to 15.6 m (well 181). The dimensions of the deposit are 31 x 11 km, the height is up to 292 m, the deposit is lithologically screened.

Deposit AC 10 2-3 in the area of ​​the well. 243 discovered at depths of 2393-2433 m. Production rate oil is 8.4 m 3 /day at Нд =1248 m (well 237). Oil-saturated thickness - 4.2 - 5 m. Dimensions 8 x 3.5 km, height up to 40 m. Type of deposit - lithologically screened.

Deposit AC 10 2-3 in the area of ​​the well. 295 was opened at depths of 2500-2566 m and is controlled by zones of clay formation. Oil-saturated thicknesses vary from 1.6 to 8.4 m. In the well. 295, 3.75 m 3 /day was obtained at Hd = 1100 m. The dimensions of the deposit are 9.7 x 4 km, height - 59 m.

The main deposit AS 10 1 was discovered at depths of 2374-2492 m. Reservoir replacement zones control the deposit on three sides, and in the south its border is drawn conditionally at a distance of 2 km from the well. 259 and 271. Oil-saturated thicknesses vary from 0.4 (well 237) to 11.8 m (well 265). Debits oil: from 2.9 m 3 /day at Нд =1064 m (well 236) to 6.4 m 3 /day at a 2 mm fitting. The dimensions of the deposit are 38 x 13 km, height up to 120 m, deposit type - lithologically screened.

Deposit AC 10 1 in the area of ​​the well. 420 was discovered at depths of 2480-2496 m. The dimensions of the deposit are 4.5 x 4 km, height - 16 m.

Deposit AC 10 1 in the area of ​​the well. 330 was discovered at depths of 2499-2528 m. The dimensions of the deposit are 6 x 4 km, height - 29 m.

Deposit AC 10 1 in the area of ​​the well. 255 was discovered at depths of 2468-2469 m. The dimensions of the deposit are 4 x 3.2 km.

The section of the AS 10 formation is completed by the AS 10 0 productive formation. Within which three deposits were identified, located in the form of a chain of submeridian strike.

AC 10 0 deposit in the area of ​​the well. 242 was opened at depths of 2356-2427 m and is lithologically screened. Debits oil are 4.9 - 9 m 3 /day at Hd-1261-1312 m. Oil-saturated thicknesses are 2.8 - 4 m. The dimensions of the deposit are 15 x 4.5 km, height up to 58 m.

AC 10 0 deposit in the area of ​​the well. 239 discovered at depths of 2370-2433 m. Production rates oil are 2.2 - 6.5 m 3 /day at Hd-1244-1275 m. Oil-saturated thicknesses are 1.6 -2.4 m. The dimensions of the deposit are 9 x 5 km, height up to 63 m.

AC 10 0 deposit in the area of ​​the well. 180 was opened at depths of 2388-2391 m and is lithologically screened. Oil-saturated thickness - 2.6 m. Inflow oil amounted to 25.9 m 3 /day at Hd-1070 m.

The cover above the AC 10 horizon is represented by a member of clayey rocks, varying from 10 to 60 m from east to west.

Sandy-siltstone rocks of formation AC 9 have a limited distribution and are presented in the form of facies windows, gravitating mainly to the northeastern and eastern sections of the structure, as well as to the southwestern plunge.

AC 9 reservoir in the area of ​​the well. 290 was discovered at depths of 2473-2548 m and is confined to the western part of the field. Oil-saturated thicknesses range from 3.2 to 7.2 m. Flow rates oil are 1.2 - 4.75 m 3 /day at Hd - 1382-1184 m. The size of the deposit is 16.1 x 6 km, height - up to 88 m.

In the east of the field, two small deposits (6 x 3 km) were identified. Oil-saturated thicknesses vary from 0.4 to 6.8 m. Tributaries oil 6 and 5.6 m 3 /day at Hd = 1300-1258 m. The deposits are lithologically screened.

The Neocomian productive deposits are completed by formation AC 7, which has a very mosaic pattern in placement oil-bearing and aquifer fields.

The largest in area, the eastern deposit of the AS 7 formation was discovered at depths of 2291-2382 m. It is contoured on three sides by reservoir replacement zones, and in the south its border is conditional and is drawn along a line running 2 km from wells 271 and 259. The deposit is oriented to the south -west to northeast. Tributaries oil: 4.9 - 6.7 m 3 /day at Hd = 1359-875 m. Oil-saturated thicknesses vary from 0.8 to 7.8 m. The dimensions of the lithologically screened deposit are 46 x 8.5 km, height up to 91 m.

AC 7 deposit in the area of ​​well. 290 was opened at a depth of 2302-2328 m. Oil-bearing thicknesses are 1.6 - 3 m. In the well. 290 received 5.3 m 3 /day oil at P = 15 MPa. The size of the deposit is 10 x 3.6 km, height - 24 m.

AC 7 deposit in the area of ​​well. 331 was discovered at a depth of 2316-2345 m and is an arched lens-shaped body. Oil-saturated thicknesses vary from 3 to 6 m. In the well. 331 influx received oil 1.5 m 3 /day at Hd = 1511 m. Dimensions of the lithologically screened deposit are 17 x 6.5 km, height - 27 m.

AC 7 deposit in the area of ​​well. 243 was discovered at a depth of 2254-2304 m. Oil-saturated thickness 2.2-3.6 m. Dimensions 11.5 x 2.8 km, height - 51 m. In the well 243 received oil 1.84 m 3 /day at Nd-1362 m.

AC 7 deposit in the area of ​​well. 259 was discovered at a depth of 2300 m and represents a lens of sandstones. Oil-saturated thickness 5.0 m. Dimensions 4 x 3 km.

Priobskoye field

Brief geological and field characteristics of formations

Priobskoye field

Petrophysical characteristics of reservoirs

Physico-chemical characteristics oil And gas

Composition and properties of formation waters