Volga-Ural oil and gas province: characteristics, deposits and strategic importance

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

The Volga-Ural oil and gas province is extremely important for Russia. Geographically, this is a rather large zone, which stretches from the great Volga to the Ural Range. It includes Bashkortostan and covers Tatarstan. VUNGP includes Udmurtia and several regions - near Volgograd, Saratov, Samara, Astrakhan, Perm. VUNGP covers the southern zones of the region near Orenburg. The significance of this province is that natural gas, whose deposits have been discovered in the Urals, is still available in very large volumes.

Relevance of the area

Geologists, specialists in the use of natural resources, politicians and public figures unanimously agree: the oil and gas regions of the Volga-Ural province are incredibly significant and valuable for the country. It is impossible to overestimate the importance of local reserves and their role in the economy and social life of the country. As they sayexperts, throughout the country, these deposits are the second most important. Mostly natural gas was found in the center and west of the zone. In the region near Orenburg, gas condensate is estimated at 1.8 trillion cubic meters. More than two trillion cubic meters have been found in Astrakhan. The position of these deposits will be considered quite favorable, since large industrial centers are located very close. The Urals, the Volga region are rich in such. All this became the reason for the formation of a large industrial complex VUNGP.

As calculated by geologists, geographers, the Volga-Ural oil and gas province of Russia will total 670,000 sq.m. The first deposits in this area were discovered in 1929. The location area is the Ural region, Verkhnechusovskie Gorodoki. After a very short time, in 1932, another source of minerals was discovered, this time in Ishimbay. Two years later, they began to develop deposits of Permian deposits, coal. The discovery of deposits took about a decade. In 1944, for the first time in history, the region became a source of oil. The first deposit was discovered at the Tuimazy site. This is the Tatar vault, its upper southern part. In the next couple of decades, the predominantly Devonian was the source of "liquid gold". In the 29th they opened industrial oil, in the 40s they began to develop deposits. Thanks to this, VUNGP has been developing as an oil and gas base of the state for a long time. Today it is one of the largest centers for the extraction and processing of natural raw materials.

Important Features

Oil enrichment of most of the VUNGP territory is noted. Primary resources are comprehensively estimated as 74% oil, 20% free gas and about 5% dissolved. Condensate is estimated at approximately one percent. The study of the tectonics of the Volga-Ural oil and gas province showed its location on the edge of the East European Platform. The eastern and northern boundaries of the zone run along the folds of the Ural Mountains and Timan. The south of the site is limited by the syneclise near the Caspian Sea. The western border is formed by the anteclise, named after Voronezh, as well as the arch, which was given the name in honor of Syktyvkar. Here, the tectonic features are determined by the Tokmovsky, Kotelnichesky vaults.

Studies have shown that the crystalline basement is located at a depth of one to two kilometers in the area of the so-called Tatar arch. This allows us to estimate the age as Archean-Early Proterozoic. In other places, the level runs much deeper - up to five kilometers deep. These are the indicators in the area of the Birsk Saddle. The study of the section showed halo-, terrigenous, carbonate elements. Age is estimated in Riphean-Mesozoic periods.

Sedimentary cover

Studying the lithological section of the Volga-Ural oil and gas province, evaluating the age features of the zones, we studied the specific features of the rock composition in different areas. It was established that there are Riphean-Lower Vendian deposits. Such in their bulk fill the negative relief foundation forms. These are sandy, clayey zones. The composition in the main percentage is large fragments. This zone has a strongdeployment. Some scientists propose to classify this complex as transitional. Its depth is about 1.5 km.

Ordovician-Lower Devonian is a sedimentary cover that reaches depths of up to 2.9 km. This is the Ordovician, which is characterized by sand, clay. Silurian, formed by dolomite, limestone, is observed here. The Lower Devonian, as shown by geological studies of the zone, is red in color and is characterized as terrigenous. Such a cover is especially strongly developed along the edges of the zone under consideration.

Exploring the natural conditions of the Volga-Ural oil and gas province, scientists have identified a cover, which they called the Middle Devonian-Triassic. It was created by carbonates and belongs to the category of terrigenous. It has the weakest dislocation. The depth of occurrence varies from three kilometers to more than a kilometer. This case is more common than others.

Sedimentary cover: more details

VUNGP is characterized by Kungur s alts. Such are characteristic of the upper Permian block. Local inclusions of a complex of clay and sand, characterized as Mesozoic-Cenozoic, were revealed. In terms of their structural features, such zones stand out quite strongly against the background of the Paleozoic.

The sedimentary cover of the zone under consideration is distinguished by a pronounced division. There are arches, deflections are present, depressions are found. To some extent, these reflect the fundamental structural plan, but only partially.

Structural elements

Geological structure of the Volga-Ural oil and gas province - the object of studyscientists for more than a decade. It has been established that the key features of the platform cover are the vaults to which the main part of the zone belongs. These are vaults in the eastern part of the region near Orenburg, vaults named after Kama and Tatarstan, Perm and Bashkiria. Equally important for research are the vaults: Sol-Iletsky, Zhigulevsko-Pugachevsky. It is not difficult to identify them in the Carboniferous horizon, in the Devonian. Permian research shows that vaults are becoming much flatter. They are separated from each other by large depressions. Most of them are inherited. Modern geologists call the large depressions Buzulukskaya, Melekesskaya, Verkhnekamskaya. In addition to these three, there are several smaller depressions. The most significant is Visimskaya. In some areas, vaults are separated by saddles. Three main ones - named after Birsk, as well as Saraylinskaya, Sokskaya.

The study of the tectonic structure of the Volga-Ural oil and gas province, specific geological features, structures and forms showed that many vaults have several peaks at the same time. They are characterized by the presence of protrusions, shafts. Complicated structure possible due to elevation. The most significant vault in terms of area is Tatarsky. Its perimeter is estimated as 600250 km. Several peaks were found here, visible in the sediment cover. For example, the Romashkinskoye field is located near the peak, which was given the name Almetyevskaya. Two other important peaks of the arch are Kukmorskaya, Belebeevsko-Shkapovskaya.

About vaults in more detail

Bcharacteristics of the Volga-Ural oil and gas province, attention must be paid to the Perm arch. Its approximate parameters are 20090 km. The amplitude reaches hundreds of meters. It has prostrations, a box shape, an inclination. The Kosvinsko-Chusovskaya saddle, which is located on this arch, is separated by a cliff from the foredeep of the Front Urals.

The Bashkir vault is characterized by dimensions of about 170130 km. It extends to the northwest. A distinctive characteristic is the pronounced asymmetry of the structure. The top of this vault is somewhat shifted towards the southeast. A typical feature is local uplifts. Their nuclei are formed by biological germs (geologists have established: Famennian). Such herms form isometric domes.

Sol-Iletsk vault is another element that must be described when characterizing the Volga-Ural oil and gas province. Its dimensions reach 150 km in length and about 90 km in width. The amplitude exceeds half a kilometer. A distinctive feature of the arch is a triangular shape. The structure of this element of the province is horst-like. A complication was revealed in the center - a shaft named after Orenburg. It is characterized by a supralacogenic structure.

Zhigulevsko-Pugachevsky reaches a length of 350 km. The width of this vault is estimated at 200 km. The amplitude inherent in the zone is about 400 m. This is a clearly asymmetric section. The linear dislocation Vyatka system runs along the foundation surface and Dokynov layers. Geologists called this area the Kazan-Kazhimsky aulacogene. Where the zone is relatively young, the Vyatka valnaya stands out.system.

About area elements

The Volga-Ural oil and gas province includes the Buzuluk depression. Its dimensions were measured by geologists and amount to 260240 km. This zone includes two vaults and one ledge. A distinctive feature is the complicated internal structure of the cavity. There are zones of descent, there are raised areas, shafts are revealed. From the south, on board the geological formation, developed linear systems. They were found near the junction with the syneclise near the Caspian Sea. Buildings are organogenic. Their age is estimated as the Middle Devonian. Such systems are associated with uplifts found on microscopic grabens (on their sides). These blocks, according to scientists, appeared before the Devonian.

Another large depression, which is present in the Volga-Ural oil and gas province, is called Verkhnekamsk. Its dimensions are estimated at 350150 km. The typical strike of the zone is to the northwest. The depression is adjacent to several vaults, the boundaries run along the slopes. The eastern part is limestone layers dated to the Middle Devonian. From them reef formations appeared. Height reaches 60 m.

Melekes depression is another large formation in the area under consideration. Dimensions are 280140 km. The Sok saddle separates this area and the depression called the Buzuluk. In the southwestern part, one can see a gradual transition to a trough. Its name is in honor of Stavropol. The depression is distinguished by the presence of a number of zones in the form of shafts.

Not so clear

Volga-Ural oil and gasthe province is characterized by the presence of relatively small elements that provide structural individuality. Deflections that do not have compensating elements, as well as complexes of micrograbens, have been identified. A specific feature was revealed - structural plans do not correspond to those formations that are higher. The most typical example is the uncompensated system of deflections called Kamsko-Kinelskaya. It appeared in the late Devonian or early Carboniferous period. The length reaches thousands of kilometers. The system begins at the Buzuluk depression and spreads towards the Vychegda trough. Geologists believe that this system opens up in the southern regions into a depression near the Caspian Sea. In total, the section is formed by 12 deflections of small width. All of them do not have compensation elements. Length - up to 250 km. The depth in some areas reaches 400 m. The formations are mainly made of silicon, clay, and carbonates. They are characterized as bituminous. The terrigenous deposits that overlap them practically do not have areas that reflect the described system of troughs.

Oil and Gas

The Volga-Ural oil and gas province is so valuable for the country because it is rich in natural resources - this already follows from the name of the zone. Today, about two thousand deposits are known. Currently, 115 serve as sources of gas and condensate, another 650 are developed to produce "black gold". A general pattern has been established that indicates the uneven distribution of hydrocarbon accumulations in the crustplanets. Mostly reserves are localized in a few especially important deposits. A smaller part is accounted for by small deposits. Among the richest and largest is the previously mentioned Romashkinskoye. No less significant for the country and the people are those that received the names: Tuimazinskoye, Mukhanovskoye. The site, which received the name in honor of Orenburg, is very important. The deposits of the Volga-Ural oil and gas province, classified as rich and large, are those that are known to modern man as Korobkovskoye, Arlan, Kuleshovskoye. Many valuable natural gifts are obtained from the Shkapovskoye and Bavlinskoye sites.

As shown by specific studies, the deposits of the Volga-Ural oil and gas province are mainly distributed in the Vendian-Jurassic area. Resources are concentrated in the Paleozoic. The largest reserves fall on the Carboniferous, Devonian. The enrichment of the Permian era is somewhat less. Certain sources have been identified in the Riphean elements characteristic of the basin of the upper part of the Kama. According to geologists, this may signal the prospects of the lower part of the section - probably productive.

Complexes

Geologists, analyzing the core of production of the Volga-Ural oil and gas province, determined that there are about seven dozen reservoirs that are productive for development. It was decided to single out nine key complexes from them. The first was called the Riphean-Vendian. It reaches a kilometer, differs in local prevalence. Oil deposits have been discovered in the basin of the upper Kama. It is believed that inin total reserves, the significance of this block is relatively small, but so far it has not been sufficiently explored and is considered promising.

Modern production methods in the Volga-Ural oil and gas province are mainly implemented in the first key oil and gas complex. It is characterized as Middle, Upper Devonian, terrigenous in its main part. The thickness varies from 30 m to 530 m. The most promising is the development of sandstone formations, between which there are argillite packs. This zone is called the Middle Devonian-Lower Frasnian, it is called the terrigenous Devonian. Oil sources have been identified in different parts of the territory. According to geologists, this block accounts for 41% of the initial total resources of oil. It is here that the largest deposits are located - Romashkinskoye and neighboring ones. In particular, in this area there are Shkapovskoye, Tuymazinskoye deposits.

More about sources

Upper Frasnian-Tournaisian is a VUNGP block, which is predominantly reef, formed by carbonates. Its thickness varies within the limits of 275-1850 m. A specific feature is its ubiquity. Deposits in their bulk - "black gold". The deposits were found in areas associated with powerful vaults. There are quite large deposits. Among them, Kudinovskoye, Mukhanovskoye deserve special attention.

The second key oil and gas complex is the lower and middle Visean terrigenous, whose maximum thickness is estimated at more than 0.4 km. As geologists have established, sandstones and siltstones are predominantly reservoirs. Horizon with mudstones, clay is the coverregion. About 21% of gas resources, about 27% of oil resources are associated with this zone. The largest sources of natural we alth are the Arlan and Nurlat deposits.

Important Features

Key specific feature of VUNGP is a large group of oil sources on domes. Gas is mainly observed in the east and south of the zone. About 75% of all its reserves are located in a deposit relatively close to Orenburg. Since the fourth decade of the last century, 23 of the most powerful deposits have been actively developed. The level of efficiency is rated as above average. In recent years, it has been possible to discover new deposits from time to time, more often - insignificant, but sometimes - medium.