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A SHORT HISTORY AND LONG FUTURE FOR PALEOPEDOLOGY GREGORY J. RETALLACK Department of Geological Sciences, University of Oregon, Eugene, Oregon 97302, USA e-mail: gregr@uoregon.edu ABSTRACT: The concept of paleosols dates back to the eighteenth century discovery of buried soils, geological unconformities, and fossil forests, but the term paleopedology was first coined by Boris B. Polynov in 1927. During the mid-twentieth century in the United States, paleopedology became mired in debates about recognition of Quaternary paleosols, and in controversy over the red-bed problem. By the 1980s, a new generation of researchers envisaged red beds as sequences of paleosols and as important archives of paleoenvironmental change. At about the same time, Precambrian geochemists began sophisticated analyses of paleosols at major unconformities as a guide to the long history of atmospheric oxidation. It is now widely acknowledged that evidence from paleosols can inform studies of stratigraphy, sedimentology, paleoclimate, paleoecology, global change, and astrobiology. For the future, there is much additional potential for what is here termed “nomopedology,” using pedotransfer functions derived from past behavior of soils to predict global and local change in the future. Past greenhouse crises have been of varied magnitude, and paleosols reveal both levels of atmospheric CO 2 and degree of concomitant paleoclimatic change. Another future development is “astropedology”, completing a history of soils on early Earth, on other planetary bodies such as the Moon and Mars, and within meteorites formed on planetismals during the origin of the solar system.
CARBON STABLE ISOTOPE COMPOSITION OF MODERN CALCAREOUS SOIL PROFILES IN CALIFORNIA: IMPLICATIONS FOR CO 2 RECONSTRUCTIONS FROM CALCAREOUS PALEOSOLS NEIL J. TABOR AND TIMOTHY S. MYERS Roy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, Texas 75275-0395, USA e-mail: ntabor@smu.edu ERIK GULBRANSON Department of Geosciences, University of Wisconsin, Milwaukee, Wisconsin 53201, USA CRAIG RASMUSSEN Soil, Water and Environmental Science, University of Arizona, Tucson, Arizona 85721, USA AND NATHAN D. SHELDON Department of Geological Sciences, University of Michigan, Ann Arbor, Michigan 48105-1005, USA ABSTRACT: Fourteen soil profiles from California were collected in order to measure the δ 13 C of coexisting soil calcite and organic matter. Thirteen of the profiles contained a measurable amount of calcite ranging from 0.04 to 54.6 wt %. Soil calcite δ 13 CPDB (δ 13 C value vs. the calcite standard Peedee Belemnite) values range from -14.4 to 1.3‰, whereas organic matter δ 13 CPDB values range from -24.0 to - 27.7‰. The hydrology of these profiles is divided into two broad groups: (1) soils characterized by gravitydriven, piston-type vertical flow through the profile and (2) soils affected by groundwater within the profile at depths where calcite is present. The difference between soil calcite and organic matter δ 13 CPDB values, ∆ 13 C cc-om , is smaller in profiles affected by groundwater saturation as well as most Vertisols and may be a product of waterlogging. The larger ∆ 13 C cc-om values in soils with gravity-driven flow are consistent with open-system mixing of tropospheric CO 2 and CO 2 derived from in situ oxidation of soil organic matter with mean soil PCO 2 values potentially in excess of ~20,000 ppmV at the time of calcite crystallization. There is a correlation between estimates of soil PCO 2 and a value termed “E PPT-U ” (kJm2/yr) among the soil profiles characterized by gravity-driven flow. E PPT-U is the energy flux through the soil during periods of soil moisture utilization, and it is the product of water mass and temperature in the profile during the growing season. Thus, soils with high water-holding capacity/storage and/or low/high growing season temperature may form soil calcite in the presence of high soil PCO 2 , and vice versa. The results of this research have important implications for reconstructions of paleoclimate from stable carbon isotopes of calcareous paleosol profiles.
Page 2 and 3: New Frontiers in Paleopedology and
Page 6 and 7: CO 2 CONCENTRATIONS IN VERTISOLS: S
Page 8 and 9: SOIL AND LANDSCAPE MEMORY OF CLIMAT
Page 10 and 11: PALEOCLIMATIC APPLICATIONS AND MODE
Page 12 and 13: ALLUVIAL STACKING PATTERN ANALYSIS
Page 14 and 15: PROGRADING DISTRIBUTIVE FLUVIAL SYS
Page 16 and 17: SOIL DEVELOPMENT ON MODERN DISTRIBU
Page 18 and 19: A PEDOSTRATIGRAPHIC APPROACH TO NON
Page 20 and 21: oth higher temperatures and an inte
Page 22: EARLY CAMBRIAN HUMID, TROPICAL, COA

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