STUDY OF MICROSPHERULES IN THE PERMIAN-TRIASSIC BOUNDARY OF WANMO SECTION, GUIZHOU PROVINCE, CHINA, BY PIXE ANALYSIS

Many microspherules were extracted from the shale of the Permian-Trias sic boundary of Wanmo section in the Guizhou province of China. Their number abruptly increased at one place leading to an interesting patte rn similar to previous studies. The chemical patterns of these microsp erules determined by PIXE analysis were compared with previous results from magnetic components of shale and meteorites. In contention with previous studies illustrating the intrusion of microspherules into the Solar System, it is postulated that the Solar System encountered the giant molecular clouds and the microspherules of the present study cam e from there.