The Sangachal Deniz-Duvanny Deniz-Khara Zira Island field is located in the northern part of the Baku archipelago, 50 km south-west of Baku City. The field is comprised of a brachyanticline fold in the shallow shelf area of the Caspian Sea with a length of 30 km and a width of 11 km. The depth of the sea in the drilling area varies between 5-20 m.
The name of the field shows that it consists of three independent rises – Sangachal Deniz, Duvanny Deniz and Khara Zira Island. The rise of Sangachal is located in the northern part of Baku archipelago, south-east of Sangachal Cape. There is a vent of mud eruption in south-east of the rise. Some eruption sources of a mud volcano were observed in the Duvanny rise. The rise of Khara Zira Island is located 25 km south-east of Sangachal Cape where the depth of the sea is 10-20 m.
Although the seismic exploration works in the area were carried out starting from 1947, the detailed study of the area was started in 1951. In 1956-1959, geological and seismic works were continued in the research area. In 1960, seismic exploration works were carried out on Khare-Zira Island, in 1963-1964 in the Sangachal-Deniz and Duvanny Island areas, and in 1965-1966 and 1966-67 in the southeastern part of the Khara-Zira structure. Seismic exploration works carried out in 1991 covered the southeastern periclinal of the Khara-Zira structure. In 2017, based on the complex analysis of 2D seismic exploration works and WGS data in the Sangachal-Deniz-Duvanni-Deniz-Khara-Zira Island area, the surface of the productive series, V, VII, VIII, PK, KaS horizons of the productive series, diatom sediments structural maps of seismic horizons representing the surface and the bottom of Miocene sediments, thickness maps for separate intervals and dynamic depth sections were created. According to the structural map constructed according to the roof of the VII horizon, the field has a brachyanticlinal structure, it stretches in the NW - SE direction, the length of the structure is 30 km and the width is 11 km.
Exploration drilling activities in the field were started in 1951, exploration wells No. 1 and 2 with a target depth of 2000-2500 m were planned in the Duvanny-Deniz area. Well No. 1 was canceled for technical reasons and well No. 2 penetrated the clay intersection of productive series. In 1959, exploration works were carried out in the Sangachal-Deniz and Duvanny-Deniz areas, and in 1966, exploration activities were conducted in the Xezer-Zira Island area. A total of 35 wells were drilled in the Sangachal-Deniz area, 81 wells in the Duvanny-Deniz area, and 45 wells in the Xazar-Zira island area.
The structure was discovered through the mapping wells drilled in 1951. Drilling of exploration wells No. 1 and 2 in the Duvanny rise also began in that year. Drilling operations in the rises of Sangachal and Khara Zira Island started in 1959. The field’s industrial development began in 1963 when well No. 24 started to produce 250 tons of oil per day. In 1968, well No. 58 drilled in the Duvanny-Deniz field was put into operation with an output of 500,000 m3 of natural gas, which created a gas flow in the field. Drilling of well No. 562 in 1981 proved the gas and condensate content of the field.
669 wells have been drilled in the field since 1963. The highest rates of oil and condensate, and natural gas production were recorded in 1975 through 115 wells (4.814 million tons), and in 1978 through 142 wells (3.348 million m3), respectively. The water drive method was applied between 1971 and 1990 to keep ground pressure stable. As of the 1st of January 2021, a total of 73.8 million m3 of water was pumped into the layers and 10.9 million tons of oil was produced there. The extracted oil contained 9.68-12.1% paraffin, 0.05-0.44% sulphur, 8.11-26.0% silicogel tar.
As of the 1st of January 2024, 68 wells, including 67 oil and 1 gas and condensate wells have been in exploitation. 76.189 million tons of oil and condensate, and 59.997 billion m3 of gas have been produced since the beginning of the development.
Considering the potential of the field, future plans include the construction of new platforms and drilling of new wells in the IV, V and XII tectonic blocks.
The field is operated by N. Narimanov OGPD of SOCAR’s Azneft PU.