Pacific Ocean, Central

Important ore deposits are found in Zaire, Morocco, and Ganada. The U.S. Geological Survey has announced that the bottom of the north central Pacific Ocean may have cobalt-rich deposits at relatively shallow depths in water close to the the Hawaiian Islands and other U.S. Pacific territories. 

A major opportunity to test the use of " Th as a proxy for POC flux arose with the Joint Global Ocean Flux Study (JGOFS). JGOFS had as a central goal a better understanding of the ocean carbon cycle, including the flux of POC leaving the euphotic zone. Process studies were carried out in the Atlantic Ocean, Pacific Ocean, Arabian Sea and Southern Ocean. " Th profiles were obtained as a part of each process study. 

Marcantonio F, Anderson RF, Higgins S, Stute M, Schlosser P, Kubik PW (2001b) Sediment focusing in the central equatorial Pacific Ocean. Paleoceanography 16(3) 260-267 Marcantonio F, Kumar N, Stute M, Anderson RF, Seidl MA, Schlosser P, Mix A (1995) A comparative study of accumulation rates derived by He and Th isotope analysis of marine sediments. Earth Planet. Sci. Letters 133 549-555... 

Murray RW, Knowlton C, Leinen M, Mix AC, Polsky CH (2000) Export production and carbonate dissolution in the central equatorial Pacific Ocean over the past 1 Myr. Paleoceanography 15(6) 570-592... 

Saturation profiles for the northern Atlantic and Pacific oceans, and the central Indian Ocean (GEOSECS stations 31,221,450). 

Chu N-C, Johnson CM, Beard BL, German CR, Nesbitt RW, Usui A (2003) Secular Fe isotope variations in the central Pacific Ocean. Geochim Cosmochim Acta 67 A66... 

Parameters influencing the distribution of calcium carbonate with increasing water depth in equatorial Pacific sediment. Note that fi is reported as a percentage (%). Source From van Andel, Tj. H., et al. (1975). Cenozoic History and Paleoceanography of the Central Equatorial Pacific Ocean, Geological Society of America, Boulder, CO, p. 40. 

The vertical trends in POM fluxes exhibit temporal and geographic variability. This was shown in Figure 23.3, in which seasonal shifts in surface productivity were seen to affect the subsurface particle fluxes even in deep waters. Other processes that can affect the sinking flux of POM include (1) in situ production by mid-water microbes or zooplankton and (2) lateral transport of POM via advective currents. Both can produce mid-water maxima in the sinking organic matter fluxes. Geographic variability in these fluxes is common. As illustrated in Figure 23.6 for the central equatorial Pacific Ocean,... 

Relative primary productivity, POC fluxes at 105 and 3000 m, and POC sediment accumulation rates versus latitude in the central equatorial Pacific Ocean. Data are normalized to the maximum value in each transect. Survey 1 was conducted during February-March 1992 under El Nino conditions and Survey 2 from August to September 1992 under non-El Nino conditions at longitudes ranging from 135 to 140°W. Ordinate scale is reset to 1.0 at each maximum, and the absolute magnitude (mmolCm ij-i) of each parameter is given next to its maximum. Source-. From Flernes, P. J., et al. (2001). Deep-Sea Research I 48, 1999-2023. 

Atoll in the Marshall Islands, located in the West Central Pacific Ocean. Although the atoll was obliterated, literally wiped off the face of the Earth, several heavy elements, both known and unknown at that time, were detected in the aftermath of the explosion by a team of scientists led by Albert Ghiorso of the Berkeley laboratory. Einsteinium was one of these trace elements that was detected. Its existence, as well as several other discovered elements, was not announced until 1955, due to secrecy related to this new type of thermonuclear bomb. The melting and boiling points as well as the density of einsteinium are not known because of the extremely small amounts that have been produced. 

CARROLL (D.), 1969. Chlorite in central north Pacific ocean sediments. 

Fig. 2. Type of manganese nodules found in north central Pacific Ocean zone. (Woods Hole Oceanographic Institution)...

Greenhut, G.K., and Bean, B.R., Aircraft measurements of boundary-layer turbulance over the central equatorial pacific ocean, Boundary Layer Meteorology, 20, 221-41, 1981. 

Williams, P. M., and E. R. M. Druffel. 1987. Radiocarbon in dissolved organic matter in the central north Pacific Ocean. Nature 330 246—248. 

CEPEX Experiment to study the central equatorial sectors of the Pacific Ocean. 

In 1999 a band of maximum annual mean positive SAT anomalies stretched from the North American continent eastward across the Atlantic Ocean and the Eurasian continent toward the equatorial western sector of the Pacific Ocean. Minimum SAT anomalies were observed in a broad band of the central and northeastern region of the Pacific Ocean (including a decrease of SAT). Analysis of the observational data revealed the prevalence of positive temperature anomalies in many regions of the globe. The most vivid anomalous situations include both warming and cooling events (Scafetta et al., 2004). Here are some aspects of temperature variations in 1999 ... 

Cosca C.E. Feely R.A. Boutin J. Ercheto J. McPhaden M.J. Chavez F.P. and Strutton P.J. (2003). Seasonal and interannual C02 fluxes for the central and eastern equatorial Pacific Ocean as determined from fC02-SST relationships. J. Geophysical Research, 108, doi 10.1029/2000JC000677. 

Roy-Barman, M., Chen, J.H. and Wasserburg, G.J. (1996) 230Th-232Th systematics in the Central Pacific Ocean. Earth Planet. Sri. Letts, 139, 351-363. 

Typical vertical saturation profiles for the North Atlantic, North Pacific, and Central Indian oceans are presented in Figure 4.10. The profiles in the Atlantic and Indian oceans are similar in shape, but Indian Ocean waters at these GEOSECS sites are definitely more undersaturated than the Atlantic Ocean. The saturation profile in the Pacific Ocean is complex. The water column between 1 and 4 km depth is close to equilibrium with calcite. This finding is primarily the result of a broad oxygen minimum-C02 maximum in mid-water and makes choosing the saturation depth (SD) where Oc = 1 difficult (the saturation depth is also often referred to as the saturation level SL). 

A new survey designed to cover six city areas in the U.S. is now under way 187>. This will determine if the previous conclusions are still valid, and whether there have been any significant changes in lead levels in five years in either the atmosphere or people as a result of the present types of lead use. Lead levels in the marine atmosphere over the central Pacific Ocean have recently been studied for comparison with the land atmosphere 92>. 

Jahnke, R.A., Heggie, D., Emerson, S., and Graham, D. (1982) Pore waters of the central Pacific Ocean nutrient results. Earth Planet. Sci. Lett. 61, 233-256. 

Jeffrey, S.W. (1976b) A report on green algal pigments in the central North Pacific Ocean. Mar. Biol. 37, 33-37. 

Mn crusts grow slowly over millions of years, sequestering high concentrations of Pb and providing a long-term record of such changes (Christensen et al., 1997). The analysis of Fe-Mn crusts for Pb isotopic composition using laser ablation MC-ICP-MS has been employed to produce a record of Pb contributions to the central Pacific Ocean (Christensen et al., 1997). 

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