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对我国北方新生界地层的研究已有較长久的历史。在华北地区的許多不同时期的第三紀化石地点都已成为标准剖面。这些标准地层剖面多仅代表某一个时期的地层,在一个剖面上可以找到两个地貭时代的还不多。这可能是由于在第三紀时期,在华北地区的沉积較少,或者是已有的沉积遭受到剝蝕以致剖面不完整,也可能是由于研究得較少,化石发現得不多以致对若干地层未及詳細划分之故。所以含有丰富化石的比較完整的第三紀地层剖面无論对于研究
The study of the North China Cenozoic strata has a long history. Tertiary fossil sites in many different periods of North China have become standard profiles. These standard stratigraphic sections are mostly representative of strata during a certain period. There are not many times that two places can be found in one section. This may be due to the fact that during the Tertiary period there was less deposition in North China, or the existing sediments were denuded so that the profiles were incomplete. It may also be due to less research and few discoveries of fossils Stratum did not date in detail. Therefore, rich in fossils of more complete Tertiary stratigraphic profile for both research