• 责任者：Zhao Tianyu (Faculty of Earth Science ; China University of Geosciences ; Wuhan 430074 ; China) ; Feng Qinglai
• 刊名：Geological Bulletin of China
• 出版年：2013
• 卷期：32(9)
• 关键词：粘土岩 ; claystone ; 火山活动 ; volcanicity ; 广西 ; Guangxi Province
• 页码：p.1402-1409
• 图表：3 illus., 3 tables, 33 refs.
• 分类号：0803
• issnNo：ISSN1671-2552
• isbnNo：CN11-4648/P

     There exist Penman Dalong Fomaation and Lower Triassic Luolou Formation along Dongpan section crossing PTB. Da- long Formation contains Ophiceras sp., and Luolou Formation contains Ophieeras tingi Tien, suggesting that they are continuous. The evidence from paleontology indicates the PTB lies between 12-3 and 13-1A. There exists several claystone layers near the Penman Triassic boundary, and the layers have obvious volcanic debris and tuffite structure. Geochemical data also show that clay- stones have volcanogenic features. U-Th-Pb zircon isotope data show a weighted mean ^206Pb/^238U age of 254.7Ma±3.7Ma, which represents the crystallization age of the protolith of the clays, roughly identical with the zircon U-Pb age 253.4Ma±0.2Ma of the bottom boundary of the Changhsingian period. It is also shown that strong volcanic eruptions occurred in this area.