摘要
描述黑龙江省东部鸡西盆地典型的城子河组下部海相层 (包括南部条带海相层 ,即原“石河北组”)的沟鞭藻类化石 15属 19种 ,含 1新种和 1新组合种。它们可分出两个沟鞭藻组合 :Odontochitinaoperculata Muderon giatetracantha组合 (下部)和Vesperopsiszhaodongensis组合 (上部) ;讨论沟鞭藻组合的特征及其地质时代 ,并与国际上有关地层进行对比 ,认为典型的城子河组下部海相层的时代为Hauterivian晚期。据此 ,推测城子河组下部 ,即海相层及其下的地层时代属Valanginian晚期—Hauterivian晚期。
ChengziheFormationwidelydistributedineast ernHeilongjiangprovince,NEChinaisrepresented byclasticcoal bearingmeasureswithathicknessof 35 0— 2 30 0mandisgroupedbysandstone,siltstone, mudstonesandtuffs.Itstypesectionislocatedinthe JixiBasin ,easternHeilongjiang .Thepresentpaper dealswithdinoflagellatesrecoveredfromamarine blackmudstonebedintercalatedinthelowerpart(in cluding“ShihebeiFormation” ,bothareapproximate lyequivalenttoeachother)oftheChengziheForma tionintheJixiBasin .Atotalof 2 2dinoflagellatecyst taxaarerecorded ,ofwhich 19speciesreferringto 15 generaaredescribedandillustratedinthispaper,in cludingonenewspeciesandonenewcombination , Oligosphaeridium jixiensesp .nov .andCirculo diniumasymmetricum (Burger)comb .nov.They aresubdividedintotwoassemblages:( 1)TheOdon tochitinaoperculata MuderongiatetracanthaAssem blageinthelowerpartand ( 2 )TheVesperopsizhaodongensisAssemblageintheupper part.The firstassemblageischaracterizedbythepresenceof Odontochitinaoperculata ,Muderongiatetracantha , Batioladinium ?exiguum ,Gardodiniumtrabeculo sum ,Oligosphaeridium jixiensesp .nov.andby abundantPalaeoperidiniumcretaceum ,withasmall numberofKiokansium polypes,Circulodinium asymmetricum ,C .colliveri,Oligosphaeridiumcf. complex,O .totum ,Prolixosphaeridiumsp .,and rareEscharisphaeridiapocockii,Laciniadiniumxin jiangense,Nyktericystapuyangensis,etc .Thesecondassemblagerepresentsalowsalinedepositionalenvi ronmentduringtheregressionandismarkedbyusu allyabundantVesperopsiszhaodongensisandrare Palaeoperidiniumcretaceum ,Sentusidiniumminor andScenedesmuscf.dimorphus,etc.Basedon charactersofthedinoflagellateassemblagesandthe globalstratigraphicrangesofmanysignificant dinocystspecies (tableⅡ ) ,thetwoassemblagesare consideredtobeofLateHauterivianinage .Thus, theageofthelowerpartoftheChengziheFormation ispossiblytheLateValanginian—LateHauterivian .
出处
《古生物学报》
CSCD
北大核心
2000年第1期46-62,共17页
Acta Palaeontologica Sinica
基金
中国科学院古生物与古人类学科基础研究特别支持费资助!(No.96 0 3 )
中国科学院留学经费择优支持回国工作基金项目!(No.940 70 3 )资助
关键词
沟鞭藻类
城子河组
欧特里夫晚期
早白垩世
Dinoflagellates
LowerChengziheFormation
LateHauterivian
JixiBasin
