四川盆地自流井组东岳庙段植物化石及下中侏罗统的界线  

FOSSIL PLANTS FROM DONGYUEMIAO MEMBER OF THE ZILIUJING FORMATION AND LOWER-MIDDLE JURASSIC BOUNDARY IN SICHUAN BASIN, CHINA

作　　者：孟繁松[1] 李旭兵[1] 陈辉明[1] 

机构地区：[1]中国地质调查局宜昌地质矿产研究所,湖北宜昌443003

出　　处：《古生物学报》2003年第4期525-536,共12页Acta Palaeontologica Sinica

基　　金：中国地质调查局资助课题 (No .2 0 0 113 90 0 0 72 )

摘　　要：对采自四川盆地云阳一带自流井组东岳庙段 1 4属 1 8种植物化石进行了研究 ,其中描述 1个新种Stachypteris ?anomalaMeng(sp .nov .)和 1个首见于区内的种Klukiaexilis (Phillips)。东岳庙段植物组合的重要分子是从下伏珍珠冲段延续而来的 ,这表明此组合基本承袭了珍珠冲段的组合面貌。依据Dictyophyllumnilssoni,D .nathorsti,Otozamiteshsiangchiensis等尚未见于中侏罗世和自流井组明显分为两大沉积旋回 ,指出东岳庙段的时代属早侏罗世托尔期 (Toarcian)和四川盆地下In recent years, more fossil plants, including 14 genera and 18 species, have been found from the Dongyuemiao Member of the Ziliujing Formation in Sichuan Basin. Of them, a new species and a species discovered for the first time in this basin, i.e. Stachypteris? anomala Meng (sp. nov.) and Klukia exilis (Phillips), are described here. All the important elements of the plant assemblage from the Dongyuemiao Member were extended up from the Zhenzhuchong Member, which shows that this assemblage basically inherited the assemblage aspect of the Zhenzhuchong Member. On the ground that Dictyophyllum nathorsti, D. nilssoni and Otozamites hsiangchiensis have not been recorded in Middle Jurassic and the Ziliujing Formation is subdivided into two sedimentary cycles, it is suggested that the Dongyuemaio Member is of Toarcian age and the Lower Middle Jurassic boundary is placed between the Dongyuemiao Member and the Ma'anshan Member of the Ziliujing Formation.

关 键 词：下-中侏罗统 植物化石 时代 界线 东岳庙段 四川盆地 

分 类 号：Q914[天文地球—古生物学与地层学]