Stalagmite gray scale record from Wanxiang Cave during the last deglaciation and its climatic significance

• 1、College of Earth and Environmental Sciences, Lanzhou University

Abstract：The Wanxiang Cave stalagmite gray scale during the last deglaciation is mainly controlled by the chemical component and the water dynamics of the seepage water. Through the comparison with the δ18O record from Hulu Cave which reflects the variation of the Asian monsoon strength, found that the gray scale turns higher corresponds to the high δ18O value of Hulu stalagmite during H-1, indicates that during this time period, responded to the dramatic retreat of the Asian monsoon, the soil and vegetation conditions kept turn worse, the seepage water carried down more clay and detrital materials, lead to the increase of impurity in the cave sediments, weakened the transmit and enhanced the reflection of the stalagmite. On the high frequency variations, the decrease of the gray scale corresponds to the increase of stalagmite density and the higher δ18O value of Hulu stalagmite records, meanwhile, the crystal style and arrangements turns more ordinarily, and impurity in the stalagmite also reduced, this may reflects the increase of super saturation and decrease of seepage water dynamics when the monsoon retreated abruptly, illustrated that during the last deglaciation, the abruptly retreat of the Asian monsoon may coupled with the dramatically drop of environment temperature.

Keywords： Wanxiang Cave Stalagmite gray scale last deglaciation Asian monsoon Heinrich-1 event