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花海地区位于河西走廊的西段,在全新世早期和中期亚洲季风增强时,该区域降水是否很好地响应亚洲季风的变化,以及季风的水汽输送是否会影响到该区域是仍需继续探讨的问题。本文通过对花海古湖泊沉积物样品的矿物测定,分析了花海古湖泊早、中全新世湖相沉积阶段中外源碎屑矿物含量的变化,并以此重建了该区域早全新世(10.47~8.87cal ka BP)和中全新世(8.87~5.5cal ka BP)的降水变化。结果显示,早全新世时期花海湖泊外源碎屑矿物含量高于中全新世时期,表明了该区域早全新世时期的降水高于中全新世时期,反映了该区域早、中全新世千年尺度的降水变化响应了印度季风的强弱变化,降水量受到了印度季风强度的影响。在全新世中期,由于西风环流的增强,花海地区水汽输送可能受到了印度季风和西风环流的双重影响。但全新世最湿润期出现在中全新世,与早全新世降水强度高于中全新世的结果并不一致。这种差异可能主要是由于中全新世时期较低的湖面蒸发所造成的。
The Huaihai area is located in the western section of the Hexi corridor. Whether the rainfall in this region responds well to the changes in the Asian monsoon during the early and mid-Holocene Asian monsoons and whether the monsoon water vapor transport will affect this area is still to be explored The problem. In this paper, through the mineralogical determination of the samples from the sediments of Huahai ancient lakes, the changes of the extrinsic detrital minerals in the early and middle Holocene lacustrine depositional stages of the Huahai ancient lake were analyzed, and the results of the early Holocene (10.47 ~ 8.87 cal ka BP) and mid-Holocene (8.87-5.5 cal ka BP). The results show that the Exoclastic minerals in the Huaihai Lake during the Early Holocene were higher than that of the mid-Holocene, indicating that the precipitation in the Early Holocene was higher than that in the middle Holocene during the Early Holocene, indicating that the Early and Middle Holocene millennia The changes in precipitation in response to changes in the intensity of the Indian monsoon, precipitation by the Indian monsoon intensity. In the mid-Holocene, due to the enhanced westerly circulation, the water vapor transport in the flower-sea area may be affected by the Indian monsoon and the westerly circulation. However, Holocene wetlands occur in the middle Holocene, which is inconsistent with the results of the Early Holocene precipitation higher than that of the middle Holocene. This difference may be mainly due to the lower evaporation of the lake during the middle Holocene.