福建的长兴阶

CHANGXING EPOCH IN FUJIAN

福建长兴期地层发育,包括碎屑岩相的大隆组和灰岩相的长兴组,长兴组分布于大田及其与永安、漳平交界处,大隆组主要分布于闽西南地区。根据生物群特征,建立了全省长兴阶7个生物带,并和华南地区长兴阶生物群作了对比。论证了福建长兴阶底界应划在大隆组下部,以Oldhamina squamosa 为代表的含海相腕足化石层下部砂岩之底。省内通常划归翠屏山组第四段的海相层应划归长兴阶。福建的长兴组含长兴阶上部生物群,其下含长兴阶下部生物群,福建长若灰岩应为长兴阶上部,大致为大隆组中上部的相变,其所含 Palaeofusulina sinensis带相当于大隆组上部 Pseudotirolites-Pleuronodoceras 带。

There are complete strata of Changxing Epoch in Fujian Province.They consist of Dalong Formation with clastic rocksand Changxing Formation with limestoes.The distribution of Changxing Formation is restricted in the area between Zhang-ping County and Yong'an County.But Dalong Formation is distribution in Southwest Fujian area.This pape set up sevenfauna assemblages in Fujian Changxing Epoch according to the characteristics of the fauna assemblages,which are correlat-ed with the fauna assemblages of Changxing Epoch in South China.It is proved that the lowest limit of Changxing Epoch inFujian should be limited to the bottom of marine brachiopoda-bearing sandstone of the Lower Dalong Formation with Old-hamia squamosa as the representative.The Fourth member of Cuipingshan Formation in Fujian,which is the marine sedi-mentary face,should belong to Changxing Epoch.Changxing Formation in Fujian possesses the faunas of the UpperChangxing Epoch.The strata underlied it possess the faunas of the Lower Changxing Epoch.The conclusion is that theChangxing limestones in Fujian should belong to the Upper Changxing Epoch and should be the facies change of the Middle-Upper Dalong Formation.The Palaeofusulina sinensis zone in Changxing Formation is accordance with the Pseudotirolites-Pleu-ronodoceras zone in Dalong Formation.