Detrital zircon grains analyzed for U–Pb ages for sedimentary provenance studies: tectonic-driven deposition of the Resende Basin (Eocene–Oligocene) in Southeast Brazil

Journal of Sedimentary Environments(2023)

引用 0|浏览5
暂无评分
摘要
The Resende Basin (Eocene–Oligocene) is a continental taphrogenic structure associated with the Continental Rift of Southeast Brazil and includes the Itatiaia and Acácias members. While the sediment provenance of the Itatiaia member is known, such knowledge regarding the Acácias Member is lacking. This work studies U–Pb ages and Lu–Hf data analyzed by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) in detrital zircons to investigate the sandstone provenance of the Acácias Member. The results suggest that Acácias Member rocks are composed predominantly of Neoproterozoic sources (60%), significant Paleoproterozoic sources (34%), and smaller contributions from Mesoproterozoic (4%) and Archean (2%) sources. The orthogneisses of the Juiz de Fora and Quirino complexes and the metasedimentary rocks of the Andrelandia Complex and Paraíba do Sul were probably the source rocks of Archean and Paleoproterozoic materials. The metasedimentary Embú Complex may be the source of Mesoproterozoic sediments, and the granitoid bodies located south of the Resende Basin (namely, the Rio Turvo granitoid) were important Neoproterozoic origins. No Late Cretaceous ages were found in the 611 analyzed zircons, suggesting that the extensional process that originated in the basin occurred before the Itatiaia alkaline intrusions. In addition, other causes for the lack of zircon grains with the age of alkaline intrusive rocks (Morro Redondo ≈ 72–70 Ma; Itatiaia ≈ 70 Ma) is related to the basin location with a structural high. This feature could have prevented the alkaline detritus from the Itatiaia and Morro Redondo intrusive bodies from reaching the study area and restricted the supply of sediments from a fluvial system with tributaries on the northern edge. In conclusion, the U–Pb ages in the detrital zircons obtained in this work reveal that the sediments of the Resende basin were tectonically driven. Interpretations of tectonic environments that affected sediment deposition require a thorough understanding of this basin stratigraphy and factors that partitioned the sedimentary processes, such as the directions of currents and the presence of structures.
更多
查看译文
关键词
LA-ICP-MS, Geochronology, U–Pb isotopes, Lu–Hf isotopes, Detrital zircons, Sedimentary basin
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要