Oxygen and hydrogen isotope composition of meteoric water in the tropical West Pacific Ocean

δD and δ¹⁸O values in samples of meteoric water obtained in the West Pacific Ocean (7.5°～31°N,123°～ 132°E) during the autumn cruises of 1989 are measured.The results show that there are obviously different distribution features of oxygen and hydrogen isotopes between the survey area and middle and high-latitude areas.A gradient variation of δ value along the direction of the monsoon is exhibited in the survey area in the West Pacific Ocean,which can be attributed to Releigh isotope fractionation of the cloud mass.The δD and δ¹⁸O distributions of meteoric water may reflect the general feature of the monsoon flow path.