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Denis-Didier Rousseau

Publications and source records attributed to Denis-Didier Rousseau.

2 recordsLinked to original sources

Loess records

Loess is an eolian deposit, composed mainly of silt grains, which can be identified in the field as a distinct sedimentary body. It covers a significant portion of the land surface of the Earth and is one of the most important terrestrial archives of long-term dust deposition. Loess appears on almost all continents, and ranges in thickness up to several hundred of meters. Most loess sequences include buried soils (paleosols), alternating with unaltered loess layers. As the formation of loess is controlled, at least partly, by climate, alternating loess deposits and buried soils hold valuable information of Quaternary climatic and environmental conditions, especially of past wind regimes.

Book chapter

Loess records

Loess is aeolian sediment, dominated by silt-sized particles, that is identifiable in the field as a distinct sedimentary body. It covers a significant portion of the land surface of the Earth and as such constitutes one of the most important archives of long-term dust deposition. Large tracts of loess cover Europe, Asia, South America, and North America, and smaller loess bodies are found covering parts of Africa, the Middle East, New Zealand, and Australia. Loess thickness, particle size, and carbonate content decrease downwind from sources, trends that are powerful tools for reconstructing paleowinds. Many loess sections consist of relatively thick deposits of mostly unaltered sediment with intercalated paleosols. Paleosols represent periods of landscape stability when loess deposition ceased or at least slowed significantly. Studies from several continents show that loess in most regions was deposited during glacial periods and paleosols formed during interglacial and interstadial periods.

Book chapter