湖南省震旦系西冲组的建立

湖南省祁东县西冲一带震旦系，通过地层清理，发现在长安组之上、大塘坡组之下，出露的以板岩为主（下部有少量铁矿层）的一套地层，与富禄组虽有相似之处，但岩性组合的比例有较大的差异，因此，将该套地层另建新组──西冲组，其时代为早震旦世。

THE ESTABLISHMENT OF THE SINIAN XICHONG FORMATION IN HUNAN

There occur Sinian strata in the vicinity of Xichong,Qidong county , Hunan province.Through sorting strati-graphic units,it is found that a sequence of strattq dominated by slate （ with some iron-formations in the lowerpart）exposed above the Chang ’ an Formation and below the Datagpo Formation has some similarities to the FuluFormation but is nobably different from the latter in respect to the ratios of the lithologic associations. Therefore,a new formation named the Xichong Formation is establishd for this sequence of strata,whose age is Early Sinian.