Atmosphere Paleozoic

Berner, R.A. (1987) Models for carbon and sulfur cycles and atmospheric oxygen application to paleozoic geologic history. Am. J. Sci., 287, 177-196. 

Calmels D, Gaillerdet J, Brenot A, France-Lanord C (2007) Sustained sulfide oxidation by physical erosion processes in the Mackenzie River basin climatic perspectives. Geology 35 1003-1006 Came RE, Eiler JM, Veizer J, Azmy K, Brand U, Weidman CR (2007) Coupling of surface temperatures and atmospheric CO2 concentrations during the Paleozoic era. Nature 449 198-201 Cameron EM (1982) Sulphate and sulphate reduction in early Precambrian oceans. Nature 296 145-148... 

Quasi A, Hoefs J, Paul J (2006) Pedogenic carbonates as a proxy for palaeo-C02 in the Paleozoic atmosphere. Palaeogeogr Palaeochmatol Palaeoecol 242 110-125 Quay PD, TUbrook B, Wong CS (1992) Oceanic uptake of fossil fuel CO2 carbon-13 evidence. Science 256 74-79... 

D. M. Hunten, Atmospheric evolution of the terrestrial planets. Science 259, 915-920 (1993) J. F. Kasting, Earth s early atmosphere. Science 259, 920-926 (1993) R. A. Berner, Atmospheric carbon dioxide levels over phanerozoic time. Science 249, 1382-1386 (1990) R. A. Berner, Paleozoic atmospheric CO2 importance of solar radiation and plant evolution. Science 261, 68-70 (1993). 

Dudley, R. (1998). Atmospheric oxygen, giant Paleozoic insects, and the evolution of aerial locomotor performance. J. Exp. Biol. 201 1043-1051. 

The next stage in the development of the atmosphere began when formation of oxygen exceeded its consumption (Mason, 1971). This occurred in the period between 1.7 and 1.2 b.y. ago at about 1 b.y., at the boundary of the Proterozoic and Paleozoic, the amounts of Oj reached the level of the Pasteur point ( 1% of the present oxygen content), as a result of which more complex organisms could appear in the biosphere. The CO2 content at this stage was controlled by carbonate-silicate equilibria in the hydrosphere. 

Mora C. 1., Driese S. G., and Colarusso L. A. (1996) Middle to late Paleozoic atmospheric CO2 levels from soil carbonate and organic matter. Science 271, 1105—1107. 

Berner R. A. (2003) The rise of trees and their effects on Paleozoic atmospheric CO2, climate and geology. In A History of Atmospheric CO2 and its Effect on Plants, Animals, and Ecosystems (eds. T. E. Cerling, M. D. Dearing and J. R. Ehleringer). Springer (in press). 

McElwain J. C. and Chaloner W. G. (1995) Stomatal density and index of fossil plants track atmospheric carbon dioxide in the Paleozoic. Ann. Bot. 76, 389-395. 

Figure 9 Early Paleozoic changes in (a) soil differentiation as indicated by clay content (volume percent) and alumina/bases (molar ratio) of the most weathered horizon of calcareous red paleosols (b) soil bioturbation as indicated by proportion of transect in paleosols occupied by roots or burrows (percent) and by measured rooting depth (m) (c) atmospheric CO2 levels (PAL) calculated from a sedimentary mass balance model (d) maximum coal seam thickness and average thickness of at least 10 consecutive seams (m) (e) diameter of fossil plant stems and roots (m) (f) diversity of fossil land plants (number of species) (g) diversity of soil animals (number of families) (Retallack, 1997c) (reproduced from Dinofest, 1997, pp. 345-359).

A Paleozoic oceanic impact at a time of widespread anoxia would instantaneously replace the surface ocean with anoxic, sulfidic, high pco deep waters. CO2 and H2S would degass to the atmosphere CO2 would equilibrate, and H2S would oxidize. However, an H2S-rich plume could last days to weeks, and spread across the land surface (A. Pavlov, personal communication). Such a scenario may explain the F-F and P-Tr extinction events if the impactor was a comet, a smaller iridium anomaly would result and may have escaped detection. If so, only the Late Ordovician extinction remains as a likely candidate for a purely terrestrial extinction mechanism (glacio-eustatic sea-level fall causing shallow-marine habitat loss). 

Mora C. I., Driese S. G., and Seager P. G. (1991) Carbon dioxide in the Paleozoic atmosphere evidence from carbon-isotope compositions of pedogenic carbonate. Geology 19, 1017-1020. 

Berner R. A. (2000) The effect of the rise of land plants on atmospheric CO2 during the paleozoic. In Plants Invade the Land Evolutionary and Environmental Approaches (eds. P. G. Gensel and D. Edwards). Columbia University Press, New York, pp. 173-178. 

There is evidence to suggest that the late Paleozoic was a time of very elevated po, to concentrations substantially greater than observed in the modern atmosphere. Coals from the Carboniferous and Permian contain a greater abundance of fusain, a product of woody tissue combustion and charring, than observed for any period of the subsequent geologic past (Robinson, 1989, 1991 Glasspool, 2000), suggesting more abundant forest fires and by implication possibly... 

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