The field was discovered in 1979. It covers a 2,500 km2 project license area which also includes a smaller Korolev field as well as several exploratory prospects.
Tengiz reservoir is 20 km-wide and 21 km-long, with oil column measuring 1.6 km-thick across the reservoir.The city of Atyrau, 350 km north of Tengiz, is the main transport hub of Tengiz oil.
In production since 1993, Tengiz is the largest source of crude oil for Kazakhstan's CPC production stream, which is shipped to world markets from Novorossiisk on the Black Sea.
Estimated oil in place in the Tengiz field is 3.2 billion metric tonnes (25.5 billion barrels) with 200 million metric tonnes (1.6 billion barrels) in the Korolev field. The expansion, which is estimated to cost $36.8 billion, will be commercially operational by 2022.
Tengiz accounts for a 3rd of Kazakhstan’s oil output. The Tengizchevroil (TCO) partnership was formed on April 6, 1993, between Kazakhstan and Chevron. Current partners are Chevron, 50%; KazMunayGas, 20%; ExxonMobil Kazakhstan Ventures, 25%; LukArco, 5%.
Chevron values Tengiz enough that — along with partners that include Exxon Mobil — it is sinking $37 billion more into the field, even though Tengiz had already been producing oil for more than a quarter of a century.
Tengiz oil field produced nearly 30 million tons of crude oil in 2019.