A normal polarity subchron which occurs within the Matuyama reversed chron and is dated between 0.98 and 1.05 Ma ago (Bowen, 1978).
科学参考收录了60776条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。