Carbonate and siliciclastic sediments of the Marion Plateau, offshore Australia, were investigated during Ocean Drilling Program (ODP) Leg 194 (Fig. F1). In this study, we focus on the physical properties of Pliocene to late Miocene sediments at Sites 1194 (0–100 meters below sea floor [mbsf]) and 1198 (100–200 mbsf) (Table T1). Site 1194 is located east of the Northern Marion Platform in 373.9 m of water (Fig. F1B). It was drilled to 427.1 mbsf and penetrated sediment Megasequences D and B (Isern, Anselmetti, Blum, et al., 2002). From 0 to 100 mbsf, Site 1194 is dominated by mudstone and wackestone. Site 1198 is located northwest of the Southern Marion Platform in 319.4 m of water (Fig. F1B). Drilling Site 1198 to 522 mbsf recovered sediments from Megasequences D, C, and B (Isern, Anselmetti, Blum, et al., 2002). We studied Site 1198 from 100 to 200 mbsf, where the lithology is mudstone to skeletal grainstone.
We measured the sample deformation that results from an applied vertical effective stress under uniaxial strain conditions. This provides insights into the void ratio (or porosity), density, and permeability of the sediments during burial and consolidation. These properties influence heat and chemical transport in and around the Marion Plateau and affect the strength of the sediments.