西藏尼玛北部图北湖一带硅质岩中发现中三叠世放射虫化石

Discovery of Middle Triassic radiolarian fossils incherts in the vicinity of the Tubei Lake, northern Nyima, Tibet, China

摘要: 在龙木错-双湖缝合带之北图北湖一带的一套浅变质劈理化石英砂岩、粉砂质泥岩、（含砾）长石岩屑杂砂岩夹硅质岩、安山岩、含砾基性岩屑凝灰岩、安山质岩屑凝灰岩、玄武岩等组舍中发现中三叠世拉丁期放射虫动物群Sepsagon robustum Lahm，Triassocampe cE．coronata，Tcflevigata，Pararuesticyrtium cf．trattoense，Hindeosphaera spinulosa。放射虫化石的发现对北羌塘地区三叠纪地层的划分对比和地质构造发展演化的研究具有重要意义。

Abstract: A Middle Triassic Ladinian radiolarian fauna consisting of Sepsagon robustum Lahm, Triassocampe cf. coronata, T. cf. levigata, Pararuesticyrtium cf. trattoense and Hindeosphaera spinulosa is discovered in an association of low-grade metamorphic foliated quartzose sandstone, silty mudstone and (pebbly) feldspathic lithic graywacke with cherts, andesite, pebbly basic lithic tuff, andesitic lithic tuff and basalt. The discovery of the radiolarian fossils has great significance for the stratigraphic division and correlation of the Triassic and study of tectonic evolution in the northern Qiangtang area.