collected suites of samples. Using petrological, geochemical, 

 and isotope data, efforts will be made to determine age rela- 

 tionships, source of magma, and the geometry of hydrothermal 

 circulation around the ore deposit. 



Marine studies along the Philippine Transect at 18° N 

 extend across the Philippine plate from the Mariana Trench 

 to the island of Luzon. J. Hawkins (SIO) collected samples 

 of volcanic rocks from the islands of Yap and Palau at the 

 eastern edge of the plate where the processes of island-arc 

 formation can be observed in an early state of formation be- 

 fore being complicated by the processes of volcanism. Scripps, 

 Lamont, and the University of Hawaii took geophysical meas- 

 urements to relate the characteristics of the Philippine plate 

 to the complex geology of Luzon. These surveys will also 

 serve for IPOD drilling. Several test holes along the transect 

 are planned in 1977-78. 



SEATAR Data 



SEATAR data are available from NGSDC as follows: 

 Scripps Institution of Oceanography-J. Frazer, digital 

 data files containing sediment descriptions, station loca- 

 tions, and bibliographic references for 9,100 samples from 

 800 stations. 



Manganese Nodule Study 



The IDOE Manganese Nodule Study was conceived 

 during a workshop at Lamont-Doherty Geological Observatory 

 in January 1972. A multi-institutional approach was recom- 

 mended to solve the long-standing questions concerning the 

 origin, distribution, and geochemistry of this unique marine 

 resource. Proposed studies were organized into separate phases. 



Phase 1 involved compiling existing manganese nodule 

 data as a baseline for defining the future field work in the pro- 

 gram. A series of technical reports and conference proceedings 

 were published as a result of Phase 1 activities. These were 

 reported in IDOE Progress Report Volume 4, April 1974 to 

 April 1975. A project coordinator's office was also established 

 during this interval. 



Phase II of the study began in 1974 and was composed 

 of a series of cruises in an area of the northern equatorial 

 Pacific that contains extensive deposits of nodules enriched in 

 copper and nickel. Recovered samples have been distributed 

 to participating institutions for studies of the physical and 

 chemical structure of nodules, chemistry of sediments and 

 interstitial fluids, composition and structure of biogenic com- 

 ponents, rate of nodule growth, and characteristics of environ- 

 ments in which nodules occur. 



Perhaps the most significant aspect of the program dur- 

 ing Phase II was the development, deployment, and recovery 

 of a bottom ocean monitor (BOM) package. This package 

 was deployed for a period of 4 months near 11° N, 140° W. 

 It contained a camera, current meter, and nephelometer for 

 measuring suspended sediment concentration in the near-bot- 

 tom water. A preliminary analysis of the data reveals a notice- 

 able variation in suspended material over relatively short pe- 

 riods. Abundant animal life is indicated in bottom photo- 



graphs, but detailed analysis of time-lapse photographs is nec- 

 essary to determine whether the organisms significantly disturb 

 or move the nodules. 



The third phase of the program, beginning in 1977, will 

 concentrate on a detailed study of the influx, remobilization, 

 and final disposition of transition metals supplied to the deep- 

 sea floor of the central eastern Pacific. The ocean bottom moni- 

 toring package will be further developed to contain a number 

 of passive and active experiments to measure in situ chemical 

 fluxes between nodules and the surrounding sea-floor environ- 

 ment. During the remainder of phase III these instrument 

 packages will be deployed at five sites in the eastern Pacific 

 (fig. 29). 



During 1976, the program surveyed two sites in the cen- 

 tral Pacific (fig. 30) using the deep-tow system of Scripps 

 Institution. The fine scale bathymetry, side-looking sonar, and 

 photographic coverage, as well as the acoustic navigation pro- 

 vided by the deep tow allowed accurate sampling of nodules 

 from the survey areas. Two bottom monitor packages were 

 deployed in the station 20 area during August 1976 and will 

 be recovered during late February 1977. 



Manganese Nodule Data 



Manganese Nodule data are available from NGSDC as follows: 

 Hawaii Institute of Geophysics. -J. Andrews, data report 

 containing descriptions of 250 cores collected during RV 

 Kana Keoki Cruise 1971. 



Hawaii Institute of Geophysics - S. Margolis, magnetic 

 tape containing 1,734 references to literature relating to 

 manganese nodules for the period 1874-1975. 

 Scripps Institution of Oceanography-J. Greenslate, digital 

 data and descriptive information for 196 core, grab, and 

 dredge samples. 



Manganese Nodule Bibliography 



Andrews, J. E., E. Callender, C. J. Bowser, J. L. Mero, M. 

 Gauthier, M. E. Meylan, J. D. Craig, K. Binder, P. Volk, 

 A. Chave, and W. Bachman. 1974. Ferromanganese de- 

 posits of the ocean floor; Cruise Rep. MN-74-01 RV 

 Moan A Wave, Honolulu to San Diego, July 17- August 

 10, 1974. HIG-74-9, Hawaii Inst. Geophys., Univ. 

 Hawaii, 194 p. 



BOMDROP Expedition, RV Kana Keoki, MN 75-03. Opera- 

 tions report and index of samples, navigation, depth, and 

 subbottom profiler Data, Honolulu, Hawaii, 20 Nov. to 

 Honolulu, Hawaii 9 Dec. 1975, S.l.O. 31 p. 



Bonatti, E., M. Zerbi, R. Kay, and H. Rydell. 1976. Metal- 

 liferous deposits from the Apennine ophiolites: Mesozoic 

 equivalents of modern deposits from oceanic spreading 

 centers. Geol. Soc. Am. Bui. 87: 83-94. 



Greenslate, J. 1976. The IDOE'NSF Manganese Nodule 

 Project: a review of progress. MTS-IEEE Symp. Oceans- 

 76 2D1-2D9. 



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