Altered volcanic ash with highly-elevated concentrations of Nb (Ta), Zr (Hf), Ga, and rare
earth elements and yttrium (REY) is an untraditional type of critical metal deposit that has …

A Middle Permian mass extinction, first discovered in 1994, has become known as the “end-
Guadalupian event” in the literature. However, recent studies of foraminifera-and brachiopod …

Permian continental sequences from North China contain previously unrecognized
episodes of plant radiation and elevated extinction. The earliest extinction, in the Lower …

PREMISE OF THE STUDY: Noeggerathiales are an extinct group of heterosporous shrubs
and trees that were widespread and diverse during the Pennsylvanian–Permian Epochs …

Premise of research. Fern fronds are common in Late Paleozoic and Mesozoic strata. Large
tri-or multipinnate fronds are mainly preserved as impression/compressions, while …

Pteridosperms are common in the Permian floras of China and are known from both
vegetative and fertile organs in adpression assemblages and as dispersed ovules and …

Taeniopterid leaves with entire margins, prominent midribs and simple or bifurcate lateral
veins are present in many Paleozoic and Mesozoic floras globally and were a typical and …

This paper describes an osmundalean stem from the Lopingian (upper Permian) Xuanwei
Formation in eastern Yunnan Province, southwestern China. The stem of T. resinus sp. nov …

A new species of the marattialean fern trunk Psaronius Cotta is described from the Upper
Permian Cathaysian flora in the Xuanwei Formation of Guizhou Province, SW China, and …

Isolated ovules occur in many fossil plant assemblages, where they provide important
insights into seed-plant diversity and evolution. However, in many cases, the ovules cannot …