Carbonate pelagic

Heat flow affects the rate of alteration of pelagic ooze to chalk the higher the temperature, the greater the degree of cementation of the sediment. This effect on the ooze/chalk transition has been convincingly demonstrated by Wetzel (1989) in a study of compositionally similar pelagic carbonate sediments at DSDP sites 504 and 505 located south of the Costa Rica Rift zone. 

Figure 10.21. Variations in the Mg and Sr content of pelagic carbonates during the past 140 million years. (After Renard, 1986.)...

Figure 10.46. Mass-age relationships of sedimentary carbonates and examples of model fits to the mass-age data. (A) Global carbonates fitted using two approaches the best statistical approximation of total mass ("mass fit," dark line), and the best statistical mass fit constrained to intercept the value of the Pliocene mass remaining ("flux fit," dashed line). (8) Cratonic carbonates fitted using least-squares fit of mass-age data compared with exponential fit. (C) Pelagic carbonates fitted using "mass fit (solid line) and "flux fit" (dashed line) models. (After Wilkinson and Walker, 1989.)...

Manghnani M.H., Schlanger S.O. and Milholland P.D. (1980) Elastic properties related to depth of burial, strontium content and age, and diagenetic stage in pelagic carbonate sediments. In Bottom Interacting Ocean Acoustics (eds. W.A. Kupferman and F.D. Jensen), pp. . Plenum Press, New York. 

Quay et al. (1995) reported lower respiration to production ratios (1 to 1.7) in seven Amazon floodplain lakes. These ratios were derived from stable isotope ratios of dissolved oxygen in surface waters where light availability and photosynthesis are often high. The higher ratios calculated by B. R. Forsberg were based on depth-integrated rates and thus more accurately reflect the total pelagic carbon balance. 

Watkins D. K. (1989) Nanoplankton productivity fluctuations and rhythmically bedded pelagic carbonates of the Greenhorn Limestone (Upper Cretaceous). Palaeogeogr. Palaeo-climatol. Palaeoecol. 74, 75-86. 

Paull, C. K. Thierstein, H. R. 1990. Comparison of fine fraction with monospecific foraminiferal stable isotope stratigraphies from pelagic carbonates across the last Glacial termination. Marine Micropaleontology, 16, 207-217. 

Fig. 9.2 Environments of pelagic carbonate deposition a) deep-sea distribution of carbonate-rich sediments (new compilation from Archer 1996a) and b) factors controlling pelagic carbonate production and dissolution (modified from Morse and Mackenzie 1990).

Milliman, J.D. and Droxler, A.W., 1996. Neritic and pelagic carbonate sedimentation in the marine environment ignorance is not a bliss. Geologische Rundschau, 85 496-504. 

Coccolithophorids made their first appearance in the geological record in the earliest Jurassic, while planktonic foraminifers evolved somewhat later in the middle Jurassic. The appearance of these two dominant pelagic carbonate producers, and their rapid diversification in the Cretaceous, would have had major effects upon the carbonate geochemistry of the oceans. Before this, most carbonate was deposited in shallow seas, accounting for the high proportion of limestones among older rocks on the continents. Since the Mesozoic, deep-ocean basins have become enormous sinks for carbonate deposition. 

Middelboe, M., N. Kroer, N. O. G. Jorgensen, and D. Pakulski. 1998. Influence of sediment on pelagic carbon and nitrogen turnover in a shallow Danish estuary. Aquat. Microb. Ecol. 14 81-90. 

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