论文部分内容阅读
论文材料采自甘肃玉门红柳峡地区实测的5条剖面,共采集孢粉样品51件,涉及下白垩统下沟组和中沟组、渐新统火烧沟组、中新统白杨河组和上新统疏勒河组等。其中下白垩统下沟组与中沟组含有丰富的孢粉化石,火烧沟组、白杨河组和疏勒河组未发现孢粉化石。论文依据孢粉化石类别及时空分布特征划分孢粉组合,根据孢粉生态特征恢复研究区古气候,取得如下认识:1、经鉴定,下沟组蕨类植物孢子计有14属31种,包括Maculatisporites pachydermus,Lygodiumsporites pseudomaximus,L.subsimplex,Cyathidites australis,C.medicus,C.minor,C.punctatus,Deltoidospora triangulais,D.balowensis,D.minor,Pilosisporites trichopapillosus,P.notensis,P.parvus,Punctatisporites triangularis,Tenuicontactosporites cretacius,Todisporites minor,T.rotundiformis,Impardecispora purverulentar,I.granulosus,I.planiverrucata,Osmundscidites specious,O.granulata,O.parvus,Concavissmisporites punctatus,C.emarcidus,Cicatricosisporites augustus,C.australiensis和C.gracilis等;下沟组裸子植物花粉计有30属53种,包括Podocarpidites cacheutensis,P.biformis,P.major,Piceapollenites complanatiformis,Callialasporites prominulus,Jiaohepollis verus,J.priscus,Platysaccus luteus,Araucariacites australis,Cycadopites nitidus,C.subgranulosus,Pinuspollenites divulgatus,P.insignis,Parvisaccites nolus,Alisporites indarraensis,A.thomsaii,A.parvus,A.australis,Cedripites permirus,C.admirabilis,C.globulisaccatus和Pseudopicea magnifica等。中沟组蕨类植物孢子计有3属4种,包括Maculatisporites pachydermus,Impardecispora purverulentar,Lygodiumsporites pseudomaximus和L.subsimplex;中沟组裸子植物花粉30属47种,包括Piceapollenites complanatiformis,Alisporites indarraensis,A.thomsaii,A.parvus,A.australis,Callialasporites prominulus,Cedripites permirus,C.admirabilis,C.globulisaccatus,Pseudopicea magnifica,Jiaohepollis verus,J.priscus,Podocarpidites cacheutensis,P.biformis,P.major,Cycadopites nitidus,C.subgranulosus,Araucariacites australis,Pinuspollenites divulgatus,P.insignis和Parvisaccites nolus等。2、甘肃玉门红柳峡地区下白垩统孢粉化石丰富,可划分为三个组合,自下而上依次为Pinuspollenites-Cicatricosisporites-Impardecispora组合,Piceaepollenites-Monosulcites-Cyathidites组合和Piceaepollenites-Classopollis-Quadraeculina组合,所对应时代分别为Hauterivian—Barremian和Aptian—Albian期。3、孢粉组合面貌显示红柳峡地区早白垩世整体植被景观以针叶林为主,间有常绿阔叶植物,反映半湿润的温带-亚热带气候类型特征。