2016 Volume 81 Issue 3 Pages 243-255
The exploration well named METI Joetsu Kaikyu (JX) was drilled in the “Buri” structure in the Joetsu Basin from April through July, 2013. The “Buri” structure is located in the Joetsu Knoll at the eastern edge of the Sea of Japan, offshore Niigata Prefecture, Japan.
This well reached down to 3,110mMDBRT and confirmed the Haizume, Nishiyama, Shiiya (Pliocene), Upper Teradomari (Upper Miocene) and Lower Teradomari (Upper Miocene) Formations. Those formations were mainly composed of interbedded sandstone and mudstone with minor tuff. Four key beds, “P tuff”, “Q tuff”, “S tuff” and the fossil marker of “Blue Zone” which are identified in the Niigata Basin were also recognized in this well.
Several hydrocarbon shows were encountered in the target sections between the Shiiya and Lower Teradomari Formations. The methane gas shows were observed in the main part of the Shiiya Formation without any oil shows. Several minor oil and gas shows were encountered between the basal part of the Shiiya and Lower Teradomari Formations.
Although the hydrocarbon accumulations have not been discovered, valuable subsurface information such as stratigraphy, geochemistry and rock properties has been acquired in the well, which contributes to a further understanding of the petroleum system and future hydrocarbon exploration in the Joetsu Basin.
