10 



deeps, and fracture zones have been, and are still 

 being, found. When coupled with seismic and 

 sedimentary data, this work is giving us a greater 

 insight into the origin and evolution of the ocean 

 basins. These projects are centered in the Navy, 

 Coast and Geodetic Survey (ESSA) and in private 

 institutions supported by NSF and ONR. 



(2) One of the most significant recent accom- 

 plishments in oceanography was completion of an 

 ocean drilling and coring program on the conti- 

 nental shelf, continental slope, and the Blake 

 Plateau off the eastern coast of Florida. The 

 drilling took place on six sites along a transect 

 beginning about 22 miles off Jacksonville in 81 

 feet of water and extending 250 miles offshore 

 where the ocean depth is 3500 feet. The deepest 

 hole drilled extended 1050 feet below the seafloor. 

 The project was supported by NSF and involved 

 active participation by other Federal agencies. 

 The operation was conducted under the super- 

 vision of the Joint Oceanographic Institutions 

 Deep Earth Sampling (JOIDES) Committee, rep- 

 resenting the laboratories concerned. Although 

 only preliminary results are available, the success 

 of the operation was demonstrated by the recovery 

 of exceptionally deep ocean-bottom cores. Extrap- 

 olation of structure and lithology can now be made 

 from the land outward across the continental 

 shelf. Geological Survey gamma ray logs in the 

 holes indicated commercially important phospho- 

 rite beds beneath the continental shelf. Collections 

 of core samples at levels previously studied only 

 with reflection profiles will be of great value in 

 interpreting seismic data. Other benefits are: 

 stratigraphic correlation of near shore and deep 

 water fossil forms: new knowledge of the history 

 of the continental margin: reappraisal of present 

 theories about the continental shelf. Two fresh 

 water aquifers were found at depths of 500-700 

 feet, 22 miles offshore; the artesian water had a 

 head of more than 30 feet above sea level. This 

 find greatly extends the known water reserves for 

 this part of Florida. 



(4) Studies of recent lavas that have been ex- 

 truded from rifts on the ocean floor near Hawaii 

 have provided new methods for determining 

 relative movements of the sea floor and calculating 

 the age of submarine volcanic rocks. Analvses of 

 the depositional sequences of the lavas aid in the 

 interpretation of depositional environments of 



ancient geologic deposits that now form parts of 

 the land. Geochemical studies of the lavas are also 

 aiding in the investigation of the mechanism by 

 which the manganese deposits of the ocean floor 

 are formed. Results of the studies, conducted by 

 personnel of the Geological Survey's Hawaii 

 Volcano Observatory with the cooperation of the 

 Coast and Geodetic Survey, Japanese scientists 

 and others, have broad applicability to the search 

 for mineral resources both on the ocean floor and 

 on land. 



3. Survey Accomplishments 



Both the traditional mission oriented surveys of 

 the participating agencies and the oceanwide map- 

 ping surveys have shown solid accomplishments. 



a. Navy has greatly increased its survey effort to 

 meet urgent military requirements and has con- 

 tracted with industry to conduct the recently 

 inaugurated marine geophysical survey program. 

 Moreover, Navy has expanded its program to 

 include — where possible — programs of a non- 

 military nature to meet the needs of potential 

 government, academic, and industrial users. 



(1) Navy has conducted 13 separate hydro- 

 graphic surveys in support of ASW and undersea 

 warfare requirements. 



(2) Navy has completed a number of specialized 

 surveys. The AUTEC range in the Bahamas and 

 another military oceanography range near the 

 Virgin Islands were surveyed as was the coast of 

 Colombia. In addition, two ship years were 

 devoted to mine warfare studies. 



b. The ESSA survey program has significantly 

 advanced our knowledge of the ocean and in- 

 creased our ability to use this knowledge. 



(1) ESSA has accurately delineated the topog- 

 raphy, gravity field, and magnetic field, of a large 

 area of the Pacific Ocean. The area described 

 extended from the Aleutian Trench to the Ha- 

 waiian Islands. A regional pattern of elongate 

 magnetic lineations across the grain of the topog- 

 raphy in the North Pacific was discovered during 

 the Ocean Survey Program operations of the 

 PIONEER. 



(2) Scientists aboard the PIONEER discovered 

 the Andaman Sea rift valley during the Inter- 

 national Indian Ocean Expedition. 



