Etymology and distribution of 澤淵.

Sawabuchi 【澤淵】^{レベル1
Very rare}  The Japanese surnames etymology dictionary.

Mie-ken Minamimuro-gun Kihou-chou · Wakayama-ken Shinguu-shi . There is a descendant and a tale of the fallen of Heike. Location unknown. Estimated in the Kamakura period. 平 Taira reference.