surface (Fairbridge, 1966). Soil profiles of cores taken during the 

 MONSOON and LUSIAD expeditions (Scripps Institute of Oceanography, 1964) 

 grade from dark brown "muds" at the surface to gray or green "muds" near 

 the core bottom. 



Sediment Identification . Two gravity cores and two trip cores 

 were obtained from Station L. The second gravity core, which had an 

 extremely high area ratio (87%) , was used to verify the sediment profile 

 at the site. The first gravity core from Station L was 283 centimeters 

 long. The top 87 centimeters were lost during the disassembly of the 

 coring apparatus. The sediment log below that depth consisted of 40 

 centimeters of red clay above 156 centimeters of greenish-gray silty 

 clay. The 90-centimeter core obtained with the trip corer seemed to 

 coincide with the top of the "intact" gravity core. Red clay was found 

 in the upper 50 centimeters of trip core. The 40-centimeter interval 

 below that depth was composed of mottled red clay and gray-green silty 

 clay. The second trip corer exhibited the same layering as the initial 

 trip corer. The Unified Classification System designated the samples 

 as inorganic silts of high compressibility (MH) . The Trilinear System 

 defines both materials as silty clays. The median diameter of the red 

 clay was 0.0019 millimeter, while the median diameter of the gray-green 

 silty clay was 0.0016 millimeter. The red clay was composed of 117o 

 sand size particles, 21% silt size, and 687„ clay size. The percentages 

 of sand, silt, and clay size particles for the other sediment were 11, 

 19, and 70, respectively. Carbonate carbon and organic carbon accounted 

 for less than 0.5% of the red clay and less than 1.57» of the gray-green 

 silty clay. 



Vane Shear Strength and Index Properties . The vane strength and 

 index properties are plotted in Figures 16 and 17. The plots show 

 several interesting trends. In Figure 16, the original and undisturbed 

 strengths increase rather consistently with depth. No large discontinuity 

 occurs when the results on the trip core are substituted for the top 

 portion of the gravity core. The strength readings from the second trip 

 core (Figure 17) correspond closely with the strength measurements made 

 on the first trip core. The second trip core also verfies the large 

 increase in original water content appearing at the 50-centimeter depth. 

 The large increase in water content seems to reflect some unique feature 

 of the mottled material. 



Station M 



Geologic Considerations . Station M is located on the south flank 

 of the Java Trench in the India-Australian Basin. The water depth at 

 the site is approximately 3,600 fathoms. Although the Java Trench 

 system collects most of the terrigenous sediments originating from the 

 north and northeast, abyssal plains still characterize the geology at 

 the site (Hamilton, 1970). Since much of western Australia is presently 



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