International Workshop on the Meishan-Cores Project

The Permian-Triassic boundary succession exposed in quarries at Meishan, South China has been extensively studied during the past twenty years. Critical results on paleontological and geochemical evidence for the Permian-Triassic mass extinction have been reported; nevertheless, many ambiguous or conflicting data remain to be clarified. Since much of the disagreements about the boundary succession could be the result of outcrop alteration of samples and/or missing very thin beds that contain anomalous geochemical signals, blind tests using a complete and fresh core are urgently needed. In order to obtain a complete succession of rock samples free from any outcrop contamination and weathering, we have launched a drilling project aimed at resolving the timing and geochemistry of Permian-Triassic Events (PTEs) at Meishan. On October 9th & 10th, an international workshop on the Meishan-cores Project was held in Nanjing Institute of Geology and Palaeontology (NIGPAS). Participants include Luann Becker (UC Santa Barbara), Samuel A. Bowring (MIT), Douglas Erwin (NMNH, Smithsonian Institution), Charles Henderson (University of Calgary, Calgary), Frank Kyte (UCLA), Richard Lane (NSF, USA), Roger Summons (MIT), Yao Yupeng (NSF China), Shang Qinghua (IVPP, CAS), Wu Yasheng (IGG, CAS), Cao Changqun, Jin Yugan, Liu Lujun, Shen Shuzhong, Wang Jun, Wang Xiandong, Wang Wei, Wang Yue, Yang Qun, and Zhu Huichen from NIGP, CAS. A morning session for eight talks was taken on October 9th. These are Characteristics of the PTB interval in NW Pangea and global Correlation problems using conodont biostratigraphy (Ch. Henderson), Evidence for an Impact Event at the Permian-Triassic boundary (L. Becker ), Primary Mineralogical and Chemical Characteristics of the Major K/T and Late Eocene Impact (F. Kyte), Molecular evidence for widespread photic zone anoxia in the Tethys sea during P-T times (R. Summons), A preliminary report on the continental Permian-Triassic boundary sections in southwestern China (Shen Shuzhong), Isotope carbon profile of the PTB continental section in N. Tianshan (Cao Changqun), The EARTHTIME Initiative, Problems and progress in High-precision U-Pb geochronology, with examples from P/Tr and Ediacaran/Cm transition (S. Bowring). The afternoon session focused on the working plan, which consists of introducing reports on the cores, microstratigraphy of Permian-Triassic boundary succession, and the proposals received, and a discussion meeting in the core chambers in which the cores from Meishan are housed are treated.