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This note reports the first discovery of Middle-Late Ordovician acritarchs from the Buqingshan ophio-lite complex of the southern ophiolite zone of East Kunlun. The acritarch assemblage is dominated with acanthomor-phids (approx. 32%) and sphaeromorphds (approx. 63%) and contains more characteristic forms, such as Lophos-phaeridium edenense, L. varum, Nothooidium sp.,? Bued-ingiisphaaeridium sp., Visbysphaera sp., Strophomorpha sp., etc. In addition, some tube-like fragments and tetrads, which are recognized as affinity to terrestrial plants and usual occurrence in Late Ordovician-Early Silurian strata, are preserved together with acritarchs. All the known fossil evi-dence indicates that the strata should be Middle-Late Ordo-vician in age. It not only provides paleontological proof for the existence of Ordovician ophiolite, but also challenges the usual ideas on strata composition of the studied area and the southern ophiolite zone of East Kunlun, and the models on tectonic framework and evolution of thi
This note reports the first discovery of Middle-Late Ordovician acritarchs from the Buqingshan ophio-lite complex of the southern ophiolite zone of East Kunlun. The acritarch assemblage is dominated with acanthomor-phids (approx. 32%) and sphaeromorphs (approx. 63% ) and contains more characteristic forms, such as Lophos-phaeridium edenense, L. varum, Nothooidium sp., Bued-ingiis alphaaeridium sp., Visbysphaera sp., Strophomorpha sp., etc. In addition, some tube-like fragments and tetrads, which are recognized as affinity to terrestrial plants and usual occurrence in Late Ordovician-Early Silurian strata, are preserved together with acritarchs. All the known fossil evi-dence indicates that the strata should be Middle-Late Ordo-vician in age. It not only provides paleontological proof for the existence of Ordovician ophiolite, but also challenges the usual ideas on strata composition of the studied area and the southern ophiolite zone of East Kunlun, and the models on tectonic framework a nd evolution of thi