A Holocene Sedimentary Record from Lake Silvana, SE Brazil
Evidence For Paleoclimatic Changes From Mineral, Trace-metal And Pollen Data
- Editore:
Springer Berlin Heidelberg
- Collana:
- Lecture Notes In Earth Sciences
- EAN:
9783540662051
- ISBN:
3540662057
- Pagine:
- 112
- Formato:
- Paperback
- Lingua:
- Tedesco
Descrizione A Holocene Sedimentary Record from Lake Silvana, SE Brazil
Mineralogical-sedimentological and geochemical investigations in combination with pollen data of a 12.7-m-long dated sediment core from Lake Silvana, SE Brazil, permit the reconstruction of the climatic history over the past 10,000 years. The lowermost section (I) reflects a coarse paleosol-type sediment with abundant plant debris and rootlets; pollen indicates grassland vegetation. Section II represents fine-grained lake sediments; pollen indicates a savanna-like vegetation. Section III represents a pollen-free, coarse-grained allogenic sediment deposited under high transportation energy (increased precipitation). Section IV, a greenish sequence with increasing C content towards the top, has a pollen spectrum of present-day vegetation (semideciduous forest). The different sediment sections show a connection with erosional phases in the catchment of the lake, based on mineralogy and geochemistry, which are a response to climate development.
