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热心网友 时间:2023-09-29 09:36
全区义县期标志性代表分子及综合地层柱状对比见表2-3-1。
义县、北票地区的义县阶自下而上分为5个主要沉积层,即老公沟层、业南沟层、砖城子层或尖山层、大康堡层、朱家沟层。前面4个沉积层均含动、植物化石,后1个沉积层目前尚未见化石。老公沟层、尖山层或砖城子层和大康堡层的动物化石分为3个组合,但植物和孢粉各划分为1个组合。现分别简要论述如下:
1.义县初期
(1)Jeholosaurus-Eosestheria(Diformograpta)ovata-Cypridea reheensis(热河龙-卵圆双形雕饰东方叶肢介-热河女星介)组合
该生物化石组合以义县、北票地区的老公沟层(陆家屯层)化石为代表,与之相当的层位有建昌盆地的要路沟层,滦平盆地大店子层的底部。在义县地区,本组合主要的成员有Psittacosaurus sp.;叶肢介Eosestheria(Diformograpta)ovata;介形类 Cypridea reheensis-Limnocypridea subplana-Djungarica camarata亚组合带,其中主要有Cypridea reheensis,C.priva,C.cf.tubercularis,Limnocypridea subplana,Djungarica camarata,Eoparacypris dadianziensis,Mongolianella yixianensis,M.sanhaoensis,Rhinocypris subechinata;双壳类Arguniella sp.;腹足类Procalia sp.;鱼类 Lycoptera sp.和昆虫、植物等化石。北票陆家屯等地本组合以Jeholosaurus-Repenomamus(热河龙-爬兽)动物群为代表,主要成员有鸟臀类的Jeholosaurus shangyuanensis(上园热河龙),Liaoceratops yanzigouensis(燕子沟辽宁角龙)和Psittacosaurus sp,蜥臀类Sinovenator changii(常氏中国猎龙),Incisivosaurus gauthieri(高氏切齿龙),哺乳类Repenomamus robustus(强壮爬兽)和Gobiconodon zofiae(索菲娅戈壁兽)。
业南沟层的生物化石类型多见于义县阶下部,目前尚未发现可单独建立生物化石组合带的特征分子,暂归入Jeholosaurus—Eosestheria(Difoemograpta)ovata—Cypridea rehensis 组合内叙述。义县地区的业南沟层含恐龙类的Psittacosaurus sp;鱼类Lycoptera davidi 和Sinamia sp.;叶肢介Eosestheria(Diformograpta)cf.gongyingziensis 等,昆虫Ephemeropsis trisetalis,Sinaeschnidia cancellosa,Anthoscytina aphthosa等,尚有腹足类、植物和藻类化石。北票地区的业南沟层(下土来沟层)产叶肢介Eosestheria(Diformograpta)ovata,Clithrograpta cf.lingyuanensis;介形类Cypridea sp.,Darwinula contracta;双壳类Arguniella sp.;恐龙类Psittacosaurus sp.。
(2)冀北滦平地区大店子层下部以Yanjiestheria(Yanshania)-Cypridea stenolonga(燕山延吉叶肢介-窄长女星介)为代表,属义县初期化石组合范畴
其中叶肢介类被称为Eosestheria(Diformograpta)-Yanjiestheria(Yanshania)-Taenies theria-Eosestheria(Isoestheria)亚组合,以Eosestheria(Diformograpta),Clithrograpta 和Yanjiestheria(Yanshania)较发育为特征。介形类称Yanshanina-Cypridea-Rhinocypris 组合带,以Yanshanina繁盛,Cypridea 初步发展和较多属种的出现为特征,主要有Cypridea stenolonga,C.xitaiyangpoensis,C.tubercularis,Yanshanina elongate,Y.dabeigouensis 等。此外有鱼类Lycoptera davidi;双壳类 Arguniella liaoxiensis,A.lingyuanensis,并常伴有较多螺口盖化石。张家沟门至大店子东沟及围场清泉、隆化张三营义县阶中下部的叶肢介主要有 Eosestheria qingquanensis,E.erisopsiformia,E.aff.opima,Eosestheria(Clithrograpta)lingyuanensis,E.(C.)reticulata,Eosestheria(Dongbeiestheria)bella,Eosestheria(Diformograpta)gibba,E.(D.)ovata,E.(D.)donggouensis,E.(D.)lahaigouensis,E.(D.)ramulosa,E.(D.)cf.primitiva,E.(D.)minor,E.(D.)fengningensis,E.(D.)longiquadrata,E.(D.)takechenensis,E.(D.)heshanggouensis,E.(D.)radiata,E.(D.)weichangensis,E.(D.)shangshixiaensis,E.(D.)cf.middendorfii,Eosestheria(Filigrapta)phalosana,Eosestheria(Asioestheria)cf.sangouensis,Yanjiestheria(Yanshania)dabeigouensis,Y.(Y.)subquadrata,Y.(Y.)fengningensis,Diestheria dadianziensis,D.yixianensis,D.ovata,D.suboblonga,D.dahuichangensis,D.gigantean,Taeniestheria suboblonga,T.subququadrata,T.qingquanensis,T.reticulata,T.ovata,Jiliaoestheria sp.,Eosestheria(Isoestheria)yanbizigouensis,E.(I.)qingquanensis,Fengninggrapta huajiyingensis等;代表性成员为Eosestheria(Clithrograpta)lingyuanensis,Eosestheria(Dongbeiestheria)bella,E.(Diformograpta)gibba等,并有鱼类Lycoptera davidi 伴生。
2.义县早期
Confuciusornis-Sinosauropteryx-Haopterus 脊椎动物群,Cypridea(Cypridea)liaoningensis—Yanshanina dabeigouensis介形类亚组合带,Eosestheria-Diestheria-Jiliaoestheria-Chaoyangestheria(Digrapta)叶肢介亚组合。
该脊椎动物群是义县阶中最著名、最重要的生物化石群,拥有较庞大的生物类群。它们主要分布在义县地区的砖城子层(阜新义县盆地),金岭寺羊山盆地北票地区的尖山层,凌源三十家子盆地大新房子层,建昌盆地罗家沟层,滦平盆地大店子层,森吉图盆地桥头层(表2-3-1)。各主要盆地形成一些地方性组合和亚组合。现将几个基本并列的同期化石组合、亚组合分述于下。
(1)义县砖城子层 Eosestheria(Filigrapta)Cypridea yingwoshanensis Chrysogomphus beipiaoensis(线雕东方叶肢介英窝山女星介北票丽箭)组合
该组合产于义县地区的砖城子层,叶肢介地方性的组合为Eosestheria(Filigrapta)-Diestheria-Eosestheria(Clithrograpta)组合内的Eosestheria(Filigrapta)-Eosestheria(Diformograpta)-Eosestheria(Clithrograpta)亚组合。主要有Eosestheria sihetunensis,Eosestheria(Filigrapta)zhuanchengensis,E.(F.)jianshangouensis,E.(F.)taipinggouensis,E.(F.)phalosana,Eosestheria(Diformograpta)sp.,E.(D.)gongyingziensis,Eosestheria(Clithrograpta)cf..lingyuanensis,Neimongolestheria(Zhaomengestheria)sp.;介形类以Cypridea yingwoshanensis—Jinzhouella为代表,与Cypridea(Cypridea)liaoningensis-Yanshannina亚组合相当;昆虫主要有Sinaeschnidia cancellosa,Hagiphasma paradoxa,Karatavoblatta formosa,Habrohagla curtivenata,Anthoscytina sp.,Tetraphalerus laetus,Geotrupoides sp.,Sophogramma ple cophlebia等。此外有鸟类、植物、孢粉及藻类等化石。
(2)北票尖山层
A.Confuciusornis-Sinosauropteryx-Haopterus(孔子鸟-中华龙鸟-郝氏翼龙)脊椎动物群
该动物群多集中分布于尖山层下部沉积旋回,即双壳类、腹足类和介形类化石富集层之上。重要成员有鸟类Confuciusornis sanctus,C.sunae,C.chuanzhous,C.i,Changchen-gornis hengziensis,Jinzhouornis zhangjiyingia,Eoenantiornis buhleri,Liaoningornis longiditris;兽脚类Sinosauropteryx prima,Protarchaeopteryx robusta,Caudipteryx zoui,C.dongi,Beipiaosaurus inexpectus,Sinornithosaurus millenii;鸟臀类 Psittacosaurus sp.;翼龙类 Eosipterus yangi,Haopterus gracilis,Dendrorhynchoides curvidentatus;有鳞类Yabeinosaurus tenuis,Dalinghosaurus longidigitus;离龙类Monjurosuchus splendens;龟类Manchurochelys liaoxiensis;蛙类Liaobatrachus grabaui,Callobatrachus sanyanensis;兽类Zhanghotherium quinquecupidens,Jeholodens jenkinsi。
B.Lycoptera sinensis-Peipiaosteus-Sinamia(中华狼鳍鱼-北票鲟-中华弓鳍鱼)组合以Lycoptera sinensis,L.davidi,Peipiaosteus pani,Sinamia sp.为主。
C.Cypridea(Cypridea)liaoningensis-Yanshanina dabeigouensis(辽宁女星介-大北沟燕山介)亚组合
除亚组合代表分子外,主要有Cypridea(Ulwellia)beipiaoensis,Limnocypridea subplana,Mantellian cirdeltata,Yumenia heitizigouensis,Y.shangyuanensis,Damonella formosa,Darwinula lahailiangensis,D.dadianziensis,Timiriasevia jianshangouensis 等。珍稀脊椎动物组合带之下介形类化石类型丰富,之上较单调。
D.Ephemeropsis trisetalis Sinaeschnidia cancellosa(三尾拟蜉蝣 多室中国)组合
北票地区尖山层的昆虫化石群是构成义县期 Ephemeropsis trisetalis—Sinaeschnidia cancel-losa(三尾拟蜉蝣—多室中国)组合的主体。前述产于砖城子层的绝大部分属种亦见于尖山层,在此将其名单省略,但尖山层的箭科、古蝉科、蛉类、虻类和蜂类昆虫较发育。目前常见于尖山层的昆虫化石主要有箭科的 Liogomphus yixianensis,伪科的 Meso-corlia boreala,中生蜚蠊科的 Nipponoblatta acerba,Karatavoblatta formosa,古蝉科的 Liaocos-sus beipiaoensis,原沫蝉科的 Anomoscytina anomala,菱蜡蝉科的 Lapicixius decorus,丽脉科的Sophogramma papilionacea,Kalligramma liaoningensis,翼蛉科的 Lasiosmylus newi,草蛉科的Lembochrysa miniscula,长角蛉科的 Mesascalaphus yangi,蚊蝎蛉科的 Megabittacus beipiaoensis,Sibirobittacus atalus,巴依萨蛇蛉科的 Baissoptera grandis,Rudiraphidia liaoningensis,中蛇蛉科的 Mesoraphidia sinica,异蛇蛉科的 Xynoraphidia shangyuanensis,Alloraphidia longistigmosa,虻科的 Palaepangonius eupterus,Eopangonius pletus,鹬虻科的 Orsobrachyceron chinensis,Pauromia oresbis,原棘虻科的 Protapiocera megista,独须虻科的 Alleremonomus xingi,原舞虻科的 Helem-pis yixianensis,细蜂科的 Guvanotrupes stolis,Liaoserphus perrarus,Steleoserphus beipiaoensis,柄腹细蜂科的 Protocyrtus valis,长节锯蜂科的 Angaridyela robusta,Lethoxyela excurva,Liaoxyela antiqua 等。另外,该层的洞虾类个体数量较多,主要为 Liaoningogriphus quadripar-titus;蜘蛛类以Araneidae(圆蛛科)的成员为主。
E.Eosestheria(Filigrapta)-Eosestheria(Diformograpta)-Eosestheria(Clithrograpta)-Jiliaoestheria(线雕叶肢介-双形雕饰东方叶肢介-网雕叶肢介-冀辽叶肢介)亚组合
尖山层的叶肢介化石较丰富,亦归属于Eosestheria-Eosestheria(Filigrapta)-Eosestheria(Clithrograpta)—Diestheria 组合内的Eosestheria-Diestheria-Jiliaoestheria-Chaoyangestheria(Digrapta)亚组合范畴,北票地区地方性的组合称为Eosestheria(Filigrapta)-Eosestheria(Diformograpta)-Eosestheria(Clithrograpta)-Jiliaoestheria亚组合。
主要属种有Eosestheria sihetunensis,Eosestheria(Filigrapta)taipinggouensis,E.(F.)procta,E.(F.)jianshangouensis,E.(F.)phalosana,E.(F.)corpulepta,E.(Filigrapta)equilateralis,Eosestheria(Diformograpta)ovata,E.(D.)aff.middendorfii(Jones),E.(D.?)aff.huanghuagouensis,E.(D.)gongyingziensis,E.(D.)cf.valida,Eosestheria(Clithrograpta)lingyuanensis,Jiliaoestheria ovata,J.longipoda,J.libalanggouensis,J.huangbanjigouensis,J.zhangjiawanensis,J.nematocomperta,J.clithroformis,J.hengziensis,J.corpulepta,Eosestheria(Dongbeiestheria)yushugouensis,E.(D.)siliqua,E.(D.?)nematocomperta,Diestheria?sp.,Neimongolesthria(Zhaomengestheria)cf.exmia,Chaoyangestheria?sp.,Diestheria longinqua,D.shangyuanensis,Asioestheria sp.等。
F.Arguniella lingyuanensis-Sphaerium jeholense(凌源额尔古纳蚌-热河球蚬)组合
该组合主要分布在辽宁、冀北地区的义县阶,目前在辽西地区多见于北票地区的尖山层,主要成员有组合的代表分子和Arguniella yanshanensis,A.curta,Sphaerium anderssoni等。
G.Ptychostylus harpaeformis-Procalia vitimensis(钩形褶柱螺-维季姆前贝加尔螺)组合带
该组合带主要产于义县阶尖山层,除组合带的代表分子外,尚有Ptychostylus cf.phi-lippii,Zaptychius(Omozaptychius)angulatus,Bithynia haizhouensis等。
(3)凌源地区大新房子层
A.Confuciusornis-Sinosauropteryx-Jeholodens(孔子鸟-中华龙鸟-热河兽)组合
该组合产于凌源地区大新房子层中部,与北票地区尖山层脊椎动物化石组合带可相对比,层位亦相当。主要化石有鸟类Confuciusornis sanctus,Liaoxiornis delicatus;兽脚类 Sinosauropteryx prima,Sinornithosaurus sp.和驰龙类的成员,角龙类Psittacosaurus sp.;翼龙类;有鳞类Yabeinosaurus tenuis;离龙类Monjurosuchus splensens,Hyphalosaurus lingyuanensis;哺乳类Jeholodens jenkinsi,Sinobaata lingyuanensis,尤其出现早期具胎盘的真兽类 Eomania scansoria(攀援始祖兽)。
B.Lycoptera-Protopsephurus-Yanosteus(狼鳍鱼-原白鲟-燕鲟)组合
主要成员为Lycoptera davidi,Protopsephurus liui,Yanosteus longidorsalis,Peipiaosteus fengningensis,P.pani。
C.Eosestheria(Diformograpta)ovata-Eosestheria(Clithrograpta)lingyuanensis(卵圆双形雕饰东方叶肢介-凌源网雕东方叶肢介)亚组合
该亚组合归属于Eosestheria-Eosestheria(Filigrapta)-Eosestheria(Clithrograpta)-Diestheria组合内Eosestheria-Diestheria—Jiliaoestheria-Chaoyangestheria(Digrapta)亚组合范畴,地方性亚组合为Eosestheria(Diformograpta)ovata—Eosestheria(Clithrograpta)lingyuanensis。该亚组合主要属种除该代表分子外,还有Eosestheria(Clithrograpta)xiaodong-gouensis,Eosestheria(Diformograpta)cf.pudica,E.(D.)opipera,Paraliograpta sp.,Chaoyangestheria sp.等。
D.Cricoidoscelosus aethus-Palaeocambarus licenti(奇异环足虾-桑氏古蝲蛄)组合以大型的螯虾类(Astacids)为主,主要成员为该组合的代表分子。
除上述大新房子层的鸟类、爬行类、哺乳类、鱼类、叶肢介和虾类外,还有双壳类 Arguniella lingyuanensis,A.guadrata,Sphaerium jeholense;昆虫Karatavoblatta formosa,Alloxyelula lingyuanensis,Liaotoma linearis,Xyelites lingyuanensis,Sinocuoes valis,Lixoximordella hongi 等;介形类Cypridea sulcata,Limnocypridea subplana,Djungarica camarata,Mantelliana cirideltata,Mongolianella palmosa,Yumenia cadida等和植物化石。
(4)建昌罗家沟层Eosestheria(Clithrograpta)gujialingensis-Lycoptera davidi-Cypridea biventricostata(卵形网雕东方叶肢介-戴氏狼鳍鱼-双腹脊女星介)组合
该组合分布于建昌地区义县阶的罗家沟层下部,与凌源地区大新房子层中部在层位上基本相当。除组合的代表分子外,叶肢介还有Eosestheria(Filigrapta)taipinggouensis,Eosestheria(Diformograpta)gongyingziensis,Eosestheria(Clithrograpta?)sp.,Eosestheria sp.,Paraliograpta sp.等。隶属于Eosestheria(Filigrapta)-Eosestheria(Diformograpta)-Eosestheria(Clithrograpta)亚组合;介形类有Cypridea sinensis,Ziziphocypris linchengensis等;昆虫Sinoraphidia viridis,Alloma faciata;双壳类Arguniella sp.,Sphaerium sp.;鸟类、爬行类和鲎虫等。
(5)滦平大店子层中部Jiliaoestheria-Chaoyangestheria(Digrapta)-Cypridea subgranulosa(冀辽叶肢介-双雕朝阳叶肢介-近颗粒女星介)组合
滦平大店子层中部相当原大店子层上段(王思恩,1999)或大店子层3-4段(牛绍武等,2003)。Jiliaoestheria-Chaoyangestheria(Digrapta)-Cypridea subgranulosa组合中叶肢介归属于Eosestheria-Eosestheria(Filigrapta)-Eosestheria(Clithrograpta)-Diestheria 组合内的Eosestheria-Diestheria-Jiliaoestheria-Chaoyangestheria(Digrapta)亚组合范畴。滦平地区地方性组合为Eosestheria(Clithrograpta)-Jiliaoestheria-Chaoyangestheria(Digrapta)亚组合。以Jiliaoestheria 和Chaoyangestheria(Digrapta)为主,主要成员为Eosestheria(Clithrograpta)lingyuanensis,Eosestheria(Diformograpta)weichangensis,Jiliaoestheria striaris,J.clithroformis,J.florovalvaris,J.polyreticulata,Chaoyangestheria(Digrapta)zhangjiagouensis,C.(D.)luanpingensis,Diestheria sp.,Yanjiestheria(Yanshania)dabeigouensis,Y.(Y.)subquadrata 等;介形类化石中Cypridea较繁盛,与下伏Yanshanina-Cypridea-Rhinocypris组合带相比,Yanshanina和Djungarica两属的成员减少,被称为 Cypridea-Yanshanina-Timiriasevia(女星介-燕山介-季米里亚介)组合带,主要有 Cypridea subgranulosa(其中包括庞其清等1984年定名的Cypridea granulosa granulosa,C.granulose protogranulosa,C.granulosa subgranulosa,C.verians),C.luanpingensis,C.sulcata,Yanshanina elongate,Timiriasevia polymorpha等。此外,有双壳类Arguniella curta 和昆虫Ephemeropsis trisetalis等。
(6)丰宁森吉图桥头层Jibeinia-Yanosteus-Eosestheria(Clithrograpta)(冀北鸟-燕鲟-网雕东方叶肢介)组合
该组合分布在丰宁森吉图地区义县阶下部桥头层的中部,层位与辽西地区的大新房子层和尖山层基本相当。鸟类化石可称为Jibeinia-Hebeiornis(冀北鸟-河北鸟)组合带,成员有Jibeinia luanhera 和Hebeiornis fengningensis.。鱼类化石为Lycoptera-Yanosteus-Protopsephurus 组合带,主要有Lycoptera davidi,Yanosteus longidorsalis,Peipiaosteus fengningensis,Protopsephurus liui;叶肢介主要为Eosetheria(Diformograpta)donggouensis,Eosestheria(Clithrograpta)lingyuanensis;昆虫有Aeschnidium heishankowense(=Hebeiaeschnidia fengningensis Hong),Mesosirex volantis 等。此外,尚有腹足类、介形类和植物化石。
3.义县晚期
Jinzhousaurus-Diestheria yixianensis-Karataviella pontoforma(锦州龙-义县叠饰叶肢介-舟形卡拉达划蝽)组合
该组合分布在义县地区义县阶的大康堡层,滦平大店子层上部。大康堡层脊椎动物化石可称Jinzhousaurus-Yixianosaurus-Hyphalosaurus爬行动物群,以体大的Jinzhousaurus,个体数量颇多的Hyphalosaurus,Yixianosaurus以及反鸟类、翼手龙类较繁盛为特征,其主要代表是Jinzhousaurus yangi,Yixianosaurus longimanus;叶肢介归属于Eosestheria-Eosestheria(Filigrapta)-Eosestheria(Clithrograpta)-Diestheria 组合内的Eosestheria-Diestheria-Neimongolestheria(Plocestheria)亚组合范畴。义县地区地方性组合为Eosestheria(Filigrapta)-Eosestheria(Diformograpta)-Diestheria-Eosestheria(Clithrograpta)-Eosestheria(Dongbeiestheria)亚组合。其重要特征是Diestheria和Eosestheria(Dongbeiestheria)两属较繁盛,而与下伏Eosestheria-Diestheria-Jiliaoestheria-Chaoyangestheria(Digrapta)亚组合范畴内义县地区地方性Eosestheria(Filigrapta)-Eosestheria(Diformograpta)-Eosestheria(Clithrograpta)亚组合有所不同。目前所见,在辽西地区仅从本亚组合开始出现较发育的类型有Diestheria yixianensis,D.lijiagouensis,D.hejiaxinensis,Eosestheria(Dongbeiestheria)fuxingtunensis等,由下伏叶肢介亚组合延续来的有Diestheria longinqua,Eosestheria(Filigrapta)jianshangouensis,E.(F.)taipinggouensis,Eosestheria(Diformograpta)gongyingxziensis,Eosestheria(Dongbeiestheria)yushugouensis等。昆虫化石Ephemeropsis trisetalis,Sinaeschnidia cancellosa,Mesolygaeus laiyangensis 和Coptoclava longipoda 较常见,较重要的是Karataviella pontoforma。洞虾类Liaoningogriphus quadripartitus 个体颇多。此外,尚有植物、硅化木和少量介形类Cypridea sp.,Lycopterocypris infanitilis。
大店子层上部(王思恩于1999年称花吉营组下部的26层和27层)产叶肢介Eosesthe-ria(Clithrograpta)songyingensis,Eosestheria(Diformograpta)cf.middendorfii,Diestheria yixianensis,D.shangyuanensis。从叶肢介方面看,大店子层上部的生物组合可能相当于义县地区大康堡层的化石组合,就层位对比而言,大致相当于大康堡层至金刚山层之底但不包括金刚山层。
4.义县期Brachyphyllum longispicum-Otozamites turkestanica(长穗短叶杉-土耳其斯坦耳羽叶)植物组合
该植物化石组合主要分布在义县、北票和凌源地区的老公沟层、业南沟层、砖城子层和尖山层及大新房子层、大康堡层。由苔藓类、石松类、有节类、真蕨类、种子蕨、苏铁类、本内苏铁类、银杏类、茨康类、松柏类、买麻藤类、被子植物类组成。其中,松柏类植物占组合的首位,其余依次为本内苏铁及苏铁类、真蕨类、银杏类与茨康类、买麻藤类、被子植物类,还有一些目前无法归类的植物化石。重要分子有Selaginellites fausta,Equisetites longivaginatus,Coniopteris angustiloba,C.simplex,Eboracia lobifolia,Onychiopsis elongata,Todites major,Cladophlebis asiatica,Tyrmia acrodonta,Otozamites turkestanica,Neozamites verchojanensis,Weltrichia huangbanjigouensis,Williamsonia bella,Williamsoniella jianshangouensis,Baiera furcata,Phoenicopsis angustissima,Solenites murrayana,Leptostrobus sinensis,Pityoclas densiforlius,Scarburgia minor,Cephalotaxopsis sinensis,Podocarpites reheensis,Brachyphyllum longispicum,Pagiophyllum beipiaoense,Liaoningoclas boii,Ephedrites chenii,Gurvanella exquisita,Archaefructus liaoningensis,Problematospermum ovale等。
5.义县期Cicatricosisporites-Densoisporites-Jugella(无突肋纹孢-层环孢-纵肋单沟粉)孢粉组合
该孢粉组合分布于北票地区的尖山层和义县地区的砖城子层。据余静贤(19)研究,尖山层孢粉组合中裸子植物花粉占优势(80%~90%),主要是松柏类两气囊的花粉,另有个别的Jiaohepollis verus,Quadraeculina limbata,Classopollis classoides,Jugella sibirica;蕨类植物孢子居次(9%~16%),以Densoisporites 为主,有D.perinatus,D.microrugulatus,海金砂科孢子Cicatricosisporites australiensis 和C.mirabilis 常见,但数量较少;此外还有Cyathidites minor,Cibotiumspora juncta,Dictyotriletes granulatus,Bayanhuaspora obiculata等。王宪曾等(2000)在北票地区尖山层发现少量原始被子植Paraknemapollis,Cyclolophopollis,Magnoliapollis,Liliacidites,Prototricolpites等。义县地区砖城子层除未见被子植物花粉外,其余成分与尖山层孢粉面貌基本一致。