Tokyo Natural gas field discovered recently is one of the important hydrocarbon resources in Japan. This field is situated along the seashore of the Tokyo Bay, and the geological formations consist mainly of Neogene Tertiary and Quaternary deposits. These formations belong to the marine sediments. The high chlorinity and reducing condition of this gas-bearing underground water are easily understood from the origin and present high gas pontentiality of the field.
We surveyed this field mainly on the underground water by geochemical method.
In this paper, at the beginning, we show the locations of surveyed wells and oabserved data of them on a map and a table.
Next, we discuss the vertical distribution of chemical elements and their geochemical correlations in order to make clear the gas potentiality and productivity of the deeper horizons.
Then, we studied the regional distribution of chemical element. Thus we discussed the mutual relation of the distribution of chemical elements and geology, and obtained the regional geochemical correlation.
Finally we conclude that the noticeable area in gas prospecting consists from the, following scquence.
Southern half of Edogawa-ku, Southern part of Chuo-ku, Koto-ku, Eastern part of Minato-ku.
