The results indicate that the B/M boundary appears at the top of L7 and that the Jaramillo normal polarity subzone of the Matuyama negative polarity zone appears in the lower part of the section.

• 结果表明，B/M界线出现在L7的底部，并且在剖面下部出现了松山负向期的贾拉米洛正向极性亚带。