The Galmaz oil and gas field is located 70 km south-west of Baku, 16-18 km west of the Alat railway station, north-east of the Lower Kura Lowland, surrounded with the fields of Mishovdagh in the north-west, Kursangi in the south, and Pirsaat in the east. The field with an area of 975 ha is administratively located in the territory of Hajigabul district.
The Galmaz field is a brachianticlinal structure extending from north-west to south-east and a rise over the Kalameddin-Bandovan anticline. The structure is divided into separate blocks by tectonic faults, and the blocks are not connected to each other. The centre of this plain is the area of Galmaz mud volcano with an height of 195 m. The mud volcano located in the arch of the fold is associated with a fault that cuts the north-eastern limb. Mud springs lined up with this fault actively produce oil and gas.
The field is lithologically composed of alternating clayed and sandy siltstones. The opened thickness of the productive layer reaches 3,015 m.
The field was first explored by A.A. Ilin in 1930 and was discovered in 1955 with the first drilled well No. 87. The well was put into operation with a daily gas production of 30,000 m3. A number of exploration wells drilled in the south-western and north-eastern limbs of the Galmaz field in 1956-1958 proved that the field had oil and gas prospects. The industrial development of the field began in 1958. During the entire operation, 263 wells were drilled in the field. From the beginning of development to the 1st of January 2024, 2.733 million tons of oil and 4.064 billion m3 of gas were extracted from the field. As of the 1st of January 2024, seven gas wells are being operated in the field and the average daily production of these wells is 80,000 m3.
The Galmaz field is operated by the A. Amirov OGPD of SOCAR’s Azneft PU. Part of the field is used as underground gas storage within the Gas Storage Operations Department of Azneft PU.
Underground gas storage
The part of the Galmaz field that is used today as underground gas storages was exploited as a production fund in 1958-1974. During this period, 3.5 billion m3 of gas and 20,000 tons of oil were extracted from the wells drilled in the field. In 1974, due to the depletion of the field, it was decided to establish underground gas storage facilities in the area of the 1st tectonic block. Thus, in 1975, by the decision of the Council of Ministers of the Azerbaijan SSR, the north-western part of the field was transferred to the subordination of Azeri Gas Transportation PU (now the Gas Export Department of SOCAR). 9 gas and 10 oil wells on the balance sheet of Garadaghneft OGPD (now A. Amirov OGPD) were transferred to the balance sheet of Azeri Gas Transportation PU for underground gas storage and gas storage was established here. In 1976, the Galmaz Underground Gas Storage was put into operation. As of the 1st of January 2024, there has been a fund of 104 operational wells for underground gas storages in the Galmaz field, 101 of them are working and 3 are inactive.
The Galmaz Underground Gas Storage has an impotant role in further improving the natural gas supply to the population of the country. Expansion of the active capacity of the storage, and the introduction of new equipment and technology is one of the main priorities set by SOCAR. For this purpose, important measures - drilling new wells, reconstruction of surface equipment, gas facilities, improvement of existing infrastructure - are being taken. The limited number of wells, and the inability to use the compressor and transmission lines did not allow for maximum use of the field. As a result of complex reconstruction and construction work carried out after its transfer to SOCAR, the volume of gas injected into the Galmaz field has doubled from 4 million m3 to 8.5 million m3 per day.
Reconstruction and construction work has been carried out there to eliminate the corrosion of the Compressor Station, Gas Distribution Station, main equipment and well lines, which have been in operation for a long time. The number of compressors operating at the existing Compressor Station has been increased to 18, the Station has been equipped with new equipment and switched to the two-stage mode, and the Gas Distribution Station of the storage has been built on the basis of a new project. The new Compressor Station No. 3, commissioned in 2019, increased the daily capacity of the Galmaz underground gas storage by 30% or 13 million m3, and the active capacity of the storage increased from 1 billion to 1.5 billion m3. The injection of additional gas volumes into the storage creates conditions for the extraction and delivery of larger volumes of supplies to consumers during the winter period, when the demand for natural gas increases sharply.