Understanding the role of fluids in active accretionary prisms requires quantitative knowledge of parameters such as permeability. We report here the results of permeability tests on four samples from Ocean Drilling Program Leg 190 at the Nankai Trough accretionary prism-two from Site 1173 and two from Site 1174. Volcanic ash is present in one of the samples; otherwise, the material is hemipelagic mud. A constant-rate-of-flow technique was used at various effective pressures and rates of flow. The permeability of the four samples ranges between 10-15 and 10-18 m**2, with the ash-bearing sample showing the highest values.

Supplement to: Adatia, R H; Maltman, Alex J (2004): Data report: Initial permeability determinations on sediments from the Nankai Trough accretionary prism, ODP Sites 1173 and 1174. In: Mikada, H; Moore, GF; Taira, A; Becker, K; Moore, JC; Klaus, A (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 190/196, 1-12