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塔里木盆地北缘库车坳陷白垩系年代地层归属以往争议颇大.通过对库车坳陷北部库车河剖面和克孜勒努尔沟辅助剖面共约927.4m的地层265个采点446个样品进行的详细的磁性地层学研究,建立了该区白垩系的磁极性变化序列.钙质超微化石研究揭示巴什基奇克组顶部有晚白垩世沉积,文中进一步确认其大致与晚白垩世坎潘(Campanian)中晚期~马斯特里赫特期(Maastrichtian)相当,跨越时限约为79.1~65.6Ma,这与钙质超微化石所反映的时代特征有可比性;而亚格列木组-巴西盖组地层连续,可对比M18负向带~M3极性时,相当于贝里阿斯期(Berriasian)至巴列姆(Barremian)早期,年龄约为141.9~124.1Ma,属于早白垩世早中期.巴什基奇克组与下伏地层很可能为不整合接触,其间缺失了巴列姆(Barremian)晚期~坎潘(Campanian)早期地层.
In the northern margin of the Tarim Basin, the cretaceous chronostratigraphy of the Kuqa Depression is quite controversial.According to a total of 265 stations and 446 sites of about 927.4 m in the Kuqahe and Kizilurou gully sections in the north of the Kuqa Depression, The detailed magnetic stratigraphic study of the samples has established the sequence of magnetic polarity change of the Cretaceous in this area.The study of calcareous nannofossils reveals Late Cretaceous sediments on the top of the Bashijiqike Formation and further confirms that it is roughly consistent with the late Cretaceous The mid-late Campanian-Maastrichtian period was equivalent to a spanning period of 79.1-65.6 Ma, comparable with the age characteristics as reflected by calcareous microfossils; The Muji-Brasilian formation is continuous and can be comparable to the early Berriasian to the Barremian with an age of ~ 141.9 ~ 124.1Ma in the negative zone of M3 ~ M18, belonging to the early In the early and middle Cretaceous, the Bashijiqike Formation is likely to be unconformity with the underlying strata, with the late Barremian ~ Early Campanian formation missing.