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...

In rocks of late Paleoproterozoic and Mesoproterozoic age (ca. 1700-1000 million years ago), probable eukaryotic microfossils are widespread and well preserved, but assemblage and global diversities are low and turnover is slow. Near the Mesoproterozoic-Neoproterozoic boundary (1000 million years ago), red, green, and chromophytic algae diversified; molecular phylogenies suggest that this was p...

The Conlara Metamorphic Complex, the easternmost complex of Sierra de San Luis, is a key unit to understand relationship between late Proterozoic-Early Cambrian Pampean and Upper Cambrian-Middle Ordovician Famatinian orogenies Eastern Sierras Pampeanas. Complex extends east foothills Comechingones west up Río Guzmán shear zone. main rock types CMC are metaclastic metaigneous rocks that intruded...

Cambrian sedimentary facies are exposed throughout north part of Kerman region. Trilobites’ faunas are the most common invertebrate fossils within the Cambrian strata. The section is made of 217 m of sandstone, shale, limestone and dolomite. In this study, 153 trilobite samples including seven species and genera were identified from the Dahu section 12 Km. east of Zarand. This trilobite’s assem...

New U-Pb ages for detrital and igneous zircons constrain the depositional age and sedimentary provenance of the Beardmore Group, a siliciclastic succession that records transformation of the East Antarctic margin during Rodinia breakup and subsequent Gondwana amalgamation. We divide rocks previously mapped as the Beardmore Group into (1) an inboard late Neoproterozoic assemblage (probably ≤670 ...

During the latest Neoproterozoic to Mid-Cambrian time (580–505 Ma ago), the Earth underwent significant changes in palaeogeography that included rifting of a possible supercontinent and the near simultaneous formation of a second, slightly smaller supercontinent. It is against this tectonic backdrop that the Cambrian radiation occurred. Although the general tectonic setting during this interval...

The Meishucun Section (Yunnan Province, South China) is considered to be an important Precambrian–Cambrian boundary section, primarily because of its rich small shelly fossil record. In this article, we report the results of a sulphur isotope study of phosphate-bound sulphate from the Meishucun Section and several correlative sections in South China. Forty clastic, granular phosphorites from Me...

The increase in trace fossil diversity across the Neoproterozoic-Cambrian boundary often is presented in terms of tabulations of ichnogenera. However, a clearer picture of the increase in diversity and complexity can be reached by combining trace fossils into broad groups defined both on morphology and interpretation. This also focuses attention on looking for similarites between Neoproterozoic...

cambrian sedimentary facies are exposed throughout north part of kerman region. trilobites’ faunas are the most common invertebrate fossils within the cambrian strata. the section is made of 217 m of sandstone, shale, limestone and dolomite. in this study, 153 trilobite samples including seven species and genera were identified from the dahu section 12 km. east of zarand. this trilobite’s assem...