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 CO2 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.
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New Frontiers in Paleopedology and Terrestrial Paleoclimatology: Paleosols and Soil Surface Analog Systems
After initial breakthroughs in the discovery of fossil soils, or paleosols in the 1970s and early 1980s, the last several decades of intensified research have revealed the much greater role that these deposits can play in reconstructing ancient Earth surface systems. Research currently focuses on terrestrial paleoclimatology, in which climates of the past are reconstructed at temporal scales ranging from hundreds to millions of years, using paleosols as archives of that information. Such research requires interdisciplinary study of soils conducted in both modern and ancient environments. These issues and many others were discussed at the joint SEPM-NSF Workshop “Paleosols and Soil Surface Analog Systems”, held at Petrified Forest National Park.