A closely spaced conductivity-temperature-depth/hydrographic section was conducted off the east coast of Japan in July 1992. The southeastward section crossed the Japan Trench and the Kuroshio in the vicinity of the Kashima 1 seamount. Vertical sections of temperature, salinity, density, oxygen, and nutrients are discussed in conjunction with the movement and interleaving of water masses. Complicated vertical and horizontal mixings of water masses are inferred from the temperature and salinity relationships. Mixing processes are patchy and not continuous beneath the front. Warm, salty water found beneath the Kuroshio may result from upward mixing of water from intermediate depths. The main axis of the Kuroshio, indicated by the 14 ¿C isotherm at 200 m, is at 35.7 ¿N, 142.6 ¿E, about 20 km from the north wall surface thermal front. Geostrophic speeds exceed 170 cm s-1 at the surface; volume transport through the section is 81¿106 m3 s-1. ¿ American Geophysical Union 1994