This undated photo provided by CNOOC shows the Lingshui 36-1 gas field in waters southeast of Hainan, China's southernmost island province. The original gas in place (OGIP) of the Lingshui 36-1 gas field -- the world's first large, ultra-shallow gas field in ultra-deep waters -- has been estimated at more than 100 billion cubic meters, according to the China National Offshore Oil Corporation (CNOOC). (Photo: Xinhua)

Shenhai Yihao, or Deep Sea No.1, China's first domestic ultra-deepwater gas field project, was completed on Thursday after the construction of its second phase came to an end. 

The achievement is a milestone for the country's self-reliance in accessing deep-sea resources and shows its commitment to securing a sustainable energy supply, the China Media Group (CMG) reported.

This breakthrough followed the launch of the first phase in June 2021. Operating at a maximum depth of 1,000 meters, the latest development features the deployment of 13 world-leading technological facilities, the CMG reported.

It introduces an innovative development model that combines a subsea production system, a shallow-water conductor platform for processing and a remotely operated deep-water semi-submersible platform, according to the producer, China National Offshore Oil Corp.

In addition to the newly constructed subsea production system and the comprehensive processing platform weighing more than 14,000 tons, the project includes 12 state-of-the-art development wells and five subsea pipelines that stretch about 250 kilometers.

All offshore drilling and completion operations for the project were wrapped up by the end of August, with production testing exceeding expectations.

The project also includes the world's first 1,000-meter-deep water manifold, along with other key facilities, including the country's longest deep-water oil and gas pipeline, setting multiple industry records in deep-water operations.

These milestones were made possible by the development team's targeted efforts to overcome challenges in the complex, high-temperature and high-pressure marine environment, said the producer.

The second phase of Deep Sea No.1 has revealed more than 50 billion cubic meters (bcm) of natural gas reserves. When fully operational, it is set to increase peak annual output from 3 bcm to 4.5 bcm, according to the CMG.

Launched in June 2021 in the Lingshui waters off South China's Hainan Province, the initial phase of the Deep Sea No.1 project has confirmed geological reserves surpassing 100 bcm, making it the deepest and most challenging offshore gas field in operation in China.

In recent years, China has made notable strides in oil and gas resource extraction, transitioning swiftly from shallow to ultra-deepwater operations, reflecting the country's enhanced self-sufficiency in the sector.

Global Times