Abstract
Kaji oil field is noteworthy as the first recovered oil deposits of the stratigraphical trap type in Japan. The main oil reservoirs are developed in the lower zone of the Nishiyama formation (Uvigerina I Zonule), and it is seem that its sands are thinning out in the transgressive facies. The investigation of the regional stratigraphy for the Kita-Kambara Plain is expected to get the information of the oil development and to advance its exploration of the plain.
