Figure 16. Microrelief in the form of penetrotions, biological sculpturing, and depressions, al 820 meters 

 on the south side of the Sorrento Peninsula. Whitish objects in the figure appeared as broken pigeon eggs. 



The Structural characteristics of the sea-floor sediments found south of Capri were 

 indicated in several ways. Landing the bathyscoph on the sea-floor sediments never 

 caused the sphere to penetrate the sediment more than a few inches. Settling of the 

 craft due to a decrease in buoyancy displaced the sediment laterally. Grooves and 

 ridges were formed as the clay-silt squeezed past irregularities on the hull (fig. 8). Ob- 

 servations revealed that these grooves and the main depression remained unchanged, 

 even after several hours of exposure to the current. The sediment on the slope of Capri 

 and on the more level sea floor was firm. Cohesive blocks of sediment were seen in the 

 slump channels on the steep-south incline. Discharged ballast (iron pellets) remained 

 on the sea-floor surface in volcano-shaped piles (fig. 8, 9). The heavy guide rope (2.3 

 pounds per yard) coiled on the surface and remained in view at all times. Dragging 

 the rope produced a shallow groove that seldom exceeded a depth of 1 inch. 



A thin mantle or "crust" of buff sediment overlaying a black layer of equal thickness 

 at 1000 meters depth suggests bacterial activity reducing organic matter. The guide 

 rope effectively uncovers this dark stratum a few millimeters below the surface. Pre- 

 vailing current across the bottom apparently inhibits any thick accumulation of light 

 organic matter and hence prevents surface blackening. Disturbance of the sea fioor by 

 the bathyscoph, the guide rope, and feeding fishes generated clouds of mud with no 

 indicafion of freshly chemically reduced organic matter occurring on the surface. Eroding 



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