The sediments, at bore-hole T-3 in the upper reaches of the Urumqi River, are 10.7 mthick, and are composed mainly of till, slope-washed materials, solifluction and glacial-waterdeposits. The borehole can be divided i...The sediments, at bore-hole T-3 in the upper reaches of the Urumqi River, are 10.7 mthick, and are composed mainly of till, slope-washed materials, solifluction and glacial-waterdeposits. The borehole can be divided into six sections based on the pollen distribution, magneticsusceptibility , δ<sup>13</sup>C determinations and the diatoms distribution. There were three cold and dryperiods during the past 10.0 Ka （10<sup>3</sup> years）: before 9.3 KaBP, from 8.1 to 5.6 KaBP and 3.0 to 1.0KaBP. The three warmer periods were from 9.3 to 8.1 KaBP, 5.6 to 3.0 KaBP and since 1.0 KaBP.The Holocene maximum was between 5.6 and 3 KaBP. However, the vegetation compositions,mainly C<sub>3</sub> plants, the magnetic susceptibility and the δ<sup>13</sup>C were little changed in the study region inthe past 10 Ka. Indications are that the climate was relatively cold and stable during the past 10Ka.展开更多
文摘The sediments, at bore-hole T-3 in the upper reaches of the Urumqi River, are 10.7 mthick, and are composed mainly of till, slope-washed materials, solifluction and glacial-waterdeposits. The borehole can be divided into six sections based on the pollen distribution, magneticsusceptibility , δ<sup>13</sup>C determinations and the diatoms distribution. There were three cold and dryperiods during the past 10.0 Ka （10<sup>3</sup> years）: before 9.3 KaBP, from 8.1 to 5.6 KaBP and 3.0 to 1.0KaBP. The three warmer periods were from 9.3 to 8.1 KaBP, 5.6 to 3.0 KaBP and since 1.0 KaBP.The Holocene maximum was between 5.6 and 3 KaBP. However, the vegetation compositions,mainly C<sub>3</sub> plants, the magnetic susceptibility and the δ<sup>13</sup>C were little changed in the study region inthe past 10 Ka. Indications are that the climate was relatively cold and stable during the past 10Ka.
