clay mineralogy record of the YDY05 core

The clay minerals were dominated by illite (34%-57%) and smectite (18%-50%), with minor components of kaolinite (5%-10%) and chlorite (7%-21%). The illite contents were relatively higher during YD (with average of 53%) than during H1 (with average of 48%), exhibiting an obvious decreasing trend during the Holocene.

However, the smectite contents showed the opposite tendency, exhibiting an increasing trend throughout the Holocene. There was an overall increase in the proportions of kaolinite over the last 20 kyr. The chlorite contents varied between 7%-21%, with an average of 13%.