In the Central Pacific Ocean

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... 

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. 

Open Ocean Dissolution Experiments. The first direct studies of calcium carbonate dissolution in deep seawater were made by Peterson (41) and Berger (42). Peterson suspended spheres of Iceland spar calcite, held in pronged plastic containers, at various depths in the Central Pacific Ocean for four months. The amount of dissolution was determined by weight loss, which was small relative to the total weight of the spheres. On the same mooring Berger suspended sample chambers, which consisted of... 

Figure 6. Distribution of calcite saturation states in the Central Pacific Ocean...

Figure 11. Plot of the Peterson (41) and Berger (42) results for their water-column dissolution experiments in the Central Pacific Ocean, and the Morse and Berner (45) laboratory experiments as a function of equivalent depth. The depth of the lysocline was calculated from the data of Bramlette (49) (after Bef. 45).

Quinn et al. (1988) report a mean concentration of 16 7 nmol L (ranging from 4.9 to 22 nmol L ) for NH3 measurements in the coastal area of the northeastern Pacific Ocean. This is agreement with data reported by Genfa et al. (1998) from coastal waters of Coconut Island, Hawaii (17.4 6.9 nmol L ). Comparable concentrations have been found on a transect along 170°W in the central Pacific Ocean 10 7 nmol L (ranging from 2.8 to 21 nmol L ) (Quinn... 

McCarthy, M. D., Benner, R., Lee, C., and Fogel, M. (2007). Amino acid nitrogen isotopic fractionation patterns as indicators of zooplankton and microbial heterotrophy in plankton, dissolved and particulate organic matter in the central Pacific ocean. Qeochim. Cosmochim. Acta. 71,... 

Roy-Barman M., Chen J. H., and Wasserbtrrg G. J. (1996) 230Th—232rh systematics in the central Pacific Ocean the sotrrces and fates of thorium. Earth Planet. Sci. Lett. 139, 315-363. 

Ohkouchi N., Kawamura K., Kawahata H., and Okada H. (1999) Depth ranges of alkenone production in the central Pacific Ocean. Global Biogeochem. Cycles 13, 695-704. 

Basically, it can be stated that the sedimentation rate decreases with increasing distance from a sediment source, may this either be a continent or an area of high biogenic productivity. The highest rates of terrigenous mud formation are recorded on the shelf off river mouth s and on the continental slope, where sedimentation rates can amount up to several meters per one thousand years. Distinctly lower values are observed at detritus-starved continental margins, for example of Antarctica. The lowest sedimentation rates ever recorded lie between 1 and 3 mm ky. and are connected to deep-sea red clay in the offshore deep-sea basins (Table 1.7), especially in the central Pacific Ocean. 

Roy-Barman M, Chen JH, and Wasserburg GJ (1996) 230Th-232Th systematics in the central Pacific Ocean the sources and the fates of thorium. Earth and Planetary Science Letters 139 351-363. 

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>. 

Wen X., DeCarlo E. H., and Li Y. H. (1997) Inter-element relationships in ferromanganese crusts from the central Pacific Ocean their implications for crust genesis. Mar. Geol. 136, 277-297. 

Figure 4 Vertical profiles of total dissolved inorganic carbon (TIC) in the ocean. Curve A corresponds to a theoretical profile that would have been obtained prior to the Industrial Revolution with an atmospheric CO2 concentration of 280 ixmol mol The curve is derived from the solubility coefficients for CO2 in seawater, using a typical thermal and salinity profile from the central Pacific Ocean, and assumes that when surface water cools and sinks to become deep water it has equilibrated with atmospheric CO2. Curve B corresponds to the same calculated solubility profile of TIC, but in the year 1995, with an atmospheric CO2 concentration of 360 xmol moPk The difference between these two curves is the integrated oceanic uptake of CO2 from anthropogenic emissions since the beginning of the Industrial Revolution, with the assumption that biological processes have been in steady state (and hence have not materially affected the net influx of CO2). Curve C is a representative profile of measured TIC from the central Pacific Ocean. The difference between curve C and B is the contribution of biological processes to the uptake of CO2 in the steady state (i.e. the contribution of the biological pump to the TIC pool.) (courtesy of Doug Wallace and the World Ocean Circulation Experiment).

Gordon, D.C., 1971. Distribution of particulate organic carbon and nitrogen at an oceanic station in the central Pacific. Deep-Sea Res., 18 1127—1134. 

Sorokin, Ju.I., 1962. Microflora of the water mass of the Central Pacific Ocean. Okeanologiya, 2 922—931 (in Russian). 

In surface current systems away from the continents, Ra becomes a powerful tracer for waters that have been in contact with the continental shelf. The Ra enrichment in surface waters in the equatorial Pacific point to shelf sources off New Guinea, from where the isotope is carried eastward in the North Equatorial Counter Current. In this plume, the vertical distribution of the isotope has been used to derive vertical mixing rates. A very high accumulation of Ra is observed in the transpolar drift in the central Arctic Ocean, a signal derived from the extensive Siberian shelves. 

Pacific Ocean As shown in, nodules are abundant in the Pacific Ocean in a broad area, called the Clarion-Clipperton Zone, between about 6°N and 20°N, extending from approximately 120°W to 160°W. The limits of the area are largely determined by sedimentation rates. Nodules are also locally abundant further west in the Central Pacific Basin. Sediments in the northern part of the areas of abundant nodules in the North Pacific are red clays with accumulation rates of around 1 mm per thousand years whereas in the south they are siliceous oozes with accumulation rates of 3 mm per thousand years, or more. 

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