Precise geologic and paleoclimate data to constrain changes in the Amazon presently are restricted to time slices of the Quaternary and concentrated in specific geographic areas, whereas chronological data about species diversification span a longer time scale and are available for much larger areas. Thus, new efforts to evaluate geologic and climate changes as forcing mechanisms for the emergence of the Amazon rainforest and diversification of its biota require access to the entire Cenozoic sedimentary sequence that allows documentation of the history of Amazon environments in space and time far beyond our present state of knowledge. In some of the selected drilling sites, the Penatecaua diabase sills (CAMP representatives in Amazon), hosted in Paleozoic organic-rich shales, carbonates, and evaporites underlying the Cenozoic and Cretaceous sequences, can be continuously sampled for the first time.
One of the greatest challenges of the TADP will be to establish a reliable and well resolved chronology at all sites. To this end, a diverse and integrated set of methods will be used to establish chronological control dependent on basin, lithology, and stratigraphic unit. Multiple tools will be applied, as appropriate, to establish chronological control of sediment accumulation in lowland Amazon. The chronological methods include
● Biostratigraphy,
● Paleomagnetism,
● Radiogenic nuclides (U-Pb, 40Ar39Ar and U/Th-He),
● Cosmogenic nuclides (10Be and 26Al) dating and
● Luminescence dating (OSL, ITL, TT-OSL and pIRIR).
This suite of methods covers a broad age range allowing to determine the chronology of sediment deposition during the whole Cenozoic. The chronology of CAMP rocks will be determined by coupling paleomagnetism and radiogenic isotopes dating methods (U-Pb and 40Ar-39Ar). This will allow obtaining high-resolution chronologies for the emplacement of magmatic sills within the Paleozoic sedimentary succession.
Este é um projeto estritamente acadêmico, dedicado ao avanço das ciências, sem qualquer finalidade financeira ou econômica.
Copyright © 2025 TADP – todos direitos reservados
