期刊
EARTH-SCIENCE REVIEWS
卷 115, 期 3, 页码 163-172出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/j.earscirev.2012.08.006
关键词
Mass extinction; Conodont biostratigraphy; Carbon isotopes; Volcanic event beds; Biomarkers; Geomicrobial functional groups
资金
- National Basic Research Program of China [2011CB808800]
- NSFC Program for Innovative Research Team [40921062]
- 111 Project [B08030]
High-resolution stratigraphic records through the Permian-Triassic boundary (PTB) interval of the global stratotype section and point (GSSP) at Meishan, Zhejiang Province, China reveal that the PTB crisis was not a single, abrupt catastrophe. A bed-by-bed analysis of environmental and biotic changes makes clear that the crisis can be resolved into two discrete episodes, each consisting of three stages: A) unstably oscillating conditions, B) peak crisis conditions, and C) ameliorating conditions. The first crisis episode commenced in Bed 23, peaked in Beds 24e-26, and ameliorated in Beds 27 and 28, while the second crisis episode commenced in Bed 29, peaked in Beds 34-38, and ameliorated in Beds 39 and higher. The macroscopic mass extinctions happened not at the beginning, nor the end of each cycle, but at times when the crisis or perturbation of environments began. These extinction events do not show detectable feedbacks to concurrent environmental changes. In each episode, cyanobacteria proliferation postdated the macroscopic extinction while proliferation of green sulfur bacteria predated the environmental crisis. Causational analysis between environmental and microbial changes show that geomicrobial functional groups exercised pronounced effects on the marine C-N-S cycles and ocean redox conditions during the PTB crisis. It is possible thus that the microbial crises played an important role in strengthening or evening triggering the environmental crisis. (C) 2012 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据