in low-order streams and valley heads in the Araucaria Plateau--record of continental environmental conditions in Southern Brazil at the end of MIS 3.
Unraveling the effects of potassium metasomatism in sedimentary rocks and paleosols
, with implications for paleo weathering conditions and provenance.
Geochemical analysis of ancient soils, called paleosols
, reveal an unexpected and mysterious abrupt transition from dry to wet.
1995: Unraveling the effects of potassium metasomatism in sedimentary rocks and paleosols
, with implications for the paleoweathering conditions and provenance.
Briefly, 10 major sedimentary deposits are distinguishable, containing two major paleosols
and reaching 130 cm in total depth (Fig.
Landscape evolution in Roraima, North Amazonia, Pianation, paleosols
Reddish and greenish siliciclastic mudstone (F10) commonly displaying green mottling and carbonate nodules is interpreted as deposited in a flood plain, which underwent periodical subaerial exposure and development of paleosols
This aspect, taken in conjunction with other environmental interpretations based on paleo-dietary inferences deciphered from the meso-and micro-wear analysis of cheek teeth of several other mammalian groups as well as the changes in stable Carbon and Oxygen isotopes analyses on carbonate nodules of paleosols
, could be used towards a better understanding of the local environment and regional climate changes during the Neogene in South Asia.
Stigmaria occur in association with mineral paleosols
and beneath organic-rich horizons.
Retallack, professor of geological sciences and co-director of paleontology research at the UO Museum of Natural and Cultural History, is an internationally known expert on the recognition of paleosols
-- ancient fossilized soils contained in rocks.
The proposed environments of deposition of these deposits and their lateral and vertical variations from fluvial--lacustrine to fluvial in cycles culminating by the development of anoxic paleosols
, reflecting humid to subhumid paleoclimate are elaborated in Fig.
Paleopedology: origin, nature and dating of paleosols