Where is the Natural Gas?

KNG has been developing the Southern Kanto gas field for many years. Containing natural gas dissolved in water, the field is located primarily under Chiba Prefecture, but it extends across a wide area of the Kanto region, including Ibaraki, Saitama and Kanagawa Prefectures as well as Tokyo. Inflammable natural gas is divided into categories based on the condition in which it is found. The major categories are petroleum gas, coal gas and gas dissolved in water. Natural gas dissolved in water is methane originating from organisms broken down by high pressure in water deep below the earth's surface. The natural gas produced in Chiba is contained in the Kazusaso-gun stratum. This stratum consists of sedimentary sandstone and mudstone formed at the bottom of the sea during the Quaternary Pleistocene periods (between 3 million and 400,000 years ago). The gas is dissolved in water trapped between the layers of sandstone and mudstone. This water is called brine and, although having a high level of iodine, has a similar chemical composition to seawater.

Abundant Reserves

The Southern Kanto gas field contains a maximum recoverable reserve of 368 billion cubic meters, making it the largest field of gas dissolved in water in Japan. The natural gas reserves in the Mobara region are ideally suited for development since:

1. Remaining recoverable reserves are still large.
2. Gas bearing formations are relatively shallow.
3. The gas to water ratio (volume at surface) is high.

The recoverable reserves of natural gas in KNG fields are approximately 100 billion cubic meters. Based on current output, this is equal to approximately 600 years of production.