摘要
松辽盆地发育我国最好的白垩纪地层 ,岩石地层系统早已确立 ,但年代地层系统仍存不少争议。泉头组时代的确定是解决盆地内上、下白垩统界线的关键。泉头组上部孢粉化石丰富 ,孢粉组合以频繁出现Quanto nenpollenitescrassatus,及Schizaeoisporites,Asterisporites,Foraminisporis,Cibotiidites等属孢子 ,Quantonen pollenitestarimensis及被子植物花粉Cranwellia ,Scollardia ,Lythraites,Xinjiangpollis等少量出现为主要特征 ,与塔里木盆地库克拜组上段的孢粉组合可以比较 ,时代应为土仑期。泉头组为一套连续沉积 ,与其下的登楼库组 (阿尔必期 )为平行不整合关系。泉头组下部的孢粉组合中被子植物花粉的分异度尚低 ,但已有相当含量 (最高达30 .3% ) ,可与塔里木盆地库克拜组中、下段的孢粉组合比较 ,时代为赛诺曼期。孢粉化石的研究表明 ,松辽盆地上、下白垩统的界线应在泉头组的底界 ,即泉头组与登楼库组之间 ,而不是在泉头组的顶界。文内描述 1新种 :In terulobitesradialimbosussp .nov .,5新组合 :Neoraistrickiarareverrucosa (Chlonova)comb .nov .,Asterisporitesmontanensis (Tschudy)comb .nov .,Cranwelliastriatella (Mtschedlishvili)comb .nov .,Quantonenpollenitescausea(Stover)comb .
In the Songliao Basin of northeastern China is well-developed a non-marine Cretaceous sequence composed of 10 lithological formations (see Li Wen-ben and Liu Zhao-sheng, 1994, fig.16). Although all the formations are rich in fossils including bivalves, gastropods, conchostracans, ostracods, fishes, reptiles, charophytes, sporomorphs and plant megafossils, researchers on different fossil groups have not yet reached a consensus to chronological problems for each formation. Unfortunately, the divergence of view-points even exists among the palynologists. For the Upper-Lower Cretaceous boundary, palynologists have given two different proposals: between the Quantou and Denglouku formations (Li Wen-ben and Liu Zhao-sheng 1994) and between the Qinshankou and Quantou formations (Gao Rui-qi, 1982; Gao Rui-qi et al., 1999). Obviously, the dispute is mainly caused by the different datings of the Quantou Formation.
出处
《古生物学报》
CAS
CSCD
北大核心
2001年第2期153-176,共24页
Acta Palaeontologica Sinica
基金
国家自然科学基金!项目 1999年奖励经费成果
关键词
孢粉化石
泉头组
下白垩统界线
上白垩统
松辽盆地
地质时代
palynoflora, Quantou Formation, Cenomanian—Turonian, Upper Lower Cretaceous boundary, Songliao Basin
