DE'iiP OCllAN BIOLOGY IN RELATION TO C0N3TRUCTI0NA1- MATERIALS 



by 



James S . Nuraoka 

 Naval Civil Engineering Laboratory, Port Hueneme , California 93041 



INTRODUCTION 



The U. S. Naval Civil Engineering Laboratory at Port Hueneme, California, 

 is conducting a long-term research program to determine the effects of deep- 

 sea environment on materials. In connection with this study, submersible 

 test units (STUs) were designed and fabricated on which many test specimens 

 can be mounted. The STUs can be lowered to the ocean bottom and left for 

 long periods of exposure. To date the Laboratory has placed five STUs on 

 the ocean floor and three of these have been recovered. 



Thus far, two test sites have been selected. Test Site 1 (nominal depth 

 of 6,000 feet) is approximately 81 nautical miles southwest of Port Hueneme. 

 Test Site 2 (nominal depth of 2,500 feet) is 75 nautical miles west of 

 Port Hueneme, Additional test sites at a depth of 12,000 and 18,000 feet 

 will be chosen. 



This paper presents the materials and methods employed for attracting, 

 collecting, and evaluating deep-sea fouling and boring organisms and the 

 results of field and laboratory investigation of the recovered STU materials. 

 The materials studied were exposed for a period of 6 months at a depth of 

 2,340 feet (Test Site 2) and similar materials exposed for a period of 3 

 years at a depth of 5,300 feet (Test Site 1). 



A literature survey has already been published on fouling and boring 

 organisms and their effects upon various materials submerged in the deep 

 ocean (Muraoka , 1962). 



OCEANOGRAPHIC INFORMATION 



Concurrently with the STU program, numerous oceanographic and biological 

 data-collecting cruises to STU sites have been conducted. These have produced 

 information about the environmental parameters, such as salinity, temperature, 

 oxygen content, and biological activity. Such information is essential in 

 evaluating changes in the materials, especially corrosion of metals, exposed 

 on the ocean floor. Table 1 summarizes the environment at Test Sites 1 

 (Gray, 1965) and 2 (Reinhart, 1965). 



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