(Table 1) Description and tetrapyrrole-pigment yield at DSDP Leg 58 Holes

Nineteen core samples from the Shikoku Basin and the Daito Ridge and Basin province of the northwest Philippine Sea, obtained from DSDP Leg 58, were examined for products of chlorophyll diagenesis; we aimed at gaining a better understanding of the very early diagenetic history of sedimentary chlorophyll. We choose samples which, a priori, would allow isolation of tetrapyrrole pigments characteristic of (destructive) diagenesis modes. Studies of Japan Trench sediments (Louda et al., 1980; Baker and Louda, 1980) showed well the interplay of two main diagenesis schemes: anoxic preservation and oxic destruction. The results reported herein are a product of a preliminary investigation on sediments of scant organic matter content, which yielded limited tetrapyrrole pigment.