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罗布泊地区的AK1孔,是目前为止该区唯一的、最深的钻孔,深465.55m。依据AK1孔的岩性特征、热释光年龄、古地磁极性倒转、磁化率变化和Fe2O3含量的研究,将该地区第四纪地层划分如下:全新世为灰色—浅灰绿色色系,与晚更新世的界线划在深8.80m处,年龄值为11.5kaBP;晚更新世为杂色色系,与中更新世的界线在牙买加反向极性亚带的底界面上,深66.25m,年龄值为0.20MaBP;中更新世为褐黄色—土黄色色系,与早更新世的界线划在布容正向极性带—松山反向极性带的界面上,深235.00m,年龄值为0.73MaBP;早更新世为灰色色系,与上新世的界线在松山反向极性带—高斯正向极性带的界面上,357.50m深,年龄值为2.48MaBP;上新世为土黄色与灰色交替色系,顶部为厚8.78m的土黄色粘土层,与下更新世底部厚25.27m的灰色粗砂和含砾粗砂层相接,界限清晰。本区第四纪岩石地层、磁性地层和气候地层的底界,完全一致。因此,它是一条具有全球等时性的界线,可用以与世界其他地区的第四纪地层进行对比。
The AK1 hole in the Lop Nur area is by far the only and deepest hole in the area with a depth of 465.55m. Based on the lithology characteristics, age of thermoluminescence, reversal of paleomagnetic polarity, change of magnetic susceptibility and content of Fe2O3, the Quaternary stratigraphy of AK1 is divided as follows: Holocene is gray-light gray-green color, and Late Pleistocene boundary delineated at a depth of 8.80m, the age value of 11.5kaBP; Late Pleistocene as a variegated color, and the mid-Pleistocene boundary line in Jamaica reverse polarity sub-bottom interface, deep 66.25m, age With a value of 0.20MaBP. The mid-Pleistocene was a tawny-earthy yellow color. The boundary between the Pleistocene and Early Pleistocene was marked as 235.00 m deep at the interface of Songshan reverse polarity zone with age of 0.73MaBP. The Early Pleistocene was a gray color. The boundary between Pliocene and Pliocene was at the interface of Songshan reverse polarity -Gaussian positive polarity zone, with a depth of 357.50m and an age of 2.48MaBP. Yellow and gray alternating color, the top of the earthy clay layer 8.78m thick, and the bottom of the Pleistocene 25.27m thick gray grit and gravel grit phase phase boundaries clear. Quaternary rock strata, magnetic strata and climate strata bottom boundary, exactly the same. It is therefore a global, isochronic boundary that can be compared to Quaternary formations in other parts of the world.