نتایج جستجو برای: acritarchs

تعداد نتایج: 104  

Journal: :Precambrian Research 2021

As part of the most common eukaryotic fossils in early Ediacaran strata, acanthomorphic acritarchs are crucial for understanding biostratigraphy and evolutionary dynamics marine eukaryotes after Marinoan global glaciation. Abundant diverse have been reported from Doushantuo Formation Yangtze Gorges area, South China, different biozonation schemes proposed. However, these previously published bi...

Journal: :Earth-Science Reviews 2022

Phytoplankton form the base of most marine trophic chains and studying their past diversity at regional global scales can provide valuable insights into evolution ecosystems climate history. Using a new database more than 4000 species acritarchs prasinophytes, comprehensive investigation taxonomic trajectories this (micro)phytoplankton throughout Paleozoic is performed for first time. This data...

M. Ghavidel-syooki

Sixty-four surface samples from the Lower Palaeozoic rock units (mainly Lalun,Abastu and Abarsaj formations) near Kholin-Darreh village in the Fazel Abad area,southeastern the Caspian Sea, Northern Iran, were analyzed to determine their agerelationships. The samples of Lalun Formation were barren, but those of Abastu andAbarsaj formations contained well-preserved and abundant palynomorph entiti...

Journal: :Minerals 2023

During the Early-Middle Ordovician, Upper Yangtze Platform experienced extensive development of a distinctive set mixed siliciclastic-carbonate deposits known as Meitan Formation. To conduct comprehensive study relationship between sedimentation and sea-level changes, Hailong section, situated at southwest margin in SW China, was selected area due to its typical sedimentary sequence. This secti...

2004
Shuhai Xiao Huiming Bao Haifeng Wang Alan J. Kaufman Chuanming Zhou Guoxiang Li Xunlai Yuan Hongfei Ling

The Neoproterozoic Quruqtagh Group in eastern Chinese Tianshan consists of, in ascending order, the Bayisi, Zhaobishan, Altungol, Tereeken, Zhamoketi, Yukkengol, Shuiquan, and Hankalchough Formations. Diamictite units occur in the Bayisi–Altungol, Tereeken, and Hankalchough Formations. Our field observations confirm the glacial origin of the Tereeken and Hankalchough diamictites, but the glacia...

The Paleozoic sediments of the Chal-i-Sheh area in southwestern Iran comprising of Mila Formation, Ilebek Formation and Faraghan Formation, were studied palynologically. The samples containing well-preserved palynomorphs include acritarchs, chitinozoans, scolecodonts and pollenlspores. A palynological zonation has been established and comparison was made with other parts of the world. Based...

The excellent preservation of the acritarchs, their great abundance, diversity and good stratigraphic control permit establishment of a detailed Middle and Late Cambrian acritarch biozonation. A total of 56 palynomorph species form the basis of 10 local acritarch assemblage zones. Assemblage zones I-II occur in the lower and middle parts of the Member C of the Mila Formation and suggest Early-m...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید