Some well-preserved conifer leafy shoots and female cones from the Lower Cretaceous Changcai Formation near Fudong of Helong, eastern Jilin, Northeast China are studied. Based on gross morphological and cuticular study, a new species, Elatides helongensis Sun et Zhao (sp. nov.) is described systematically. The new species is characterized by persistent, linear or slightly falcate leaves with obtusely acute apex, attached helically on the shoots. Female cones of the new species are terminal and oval, composed of persistent helically-arranged rhomboidal scales and erect seeds. One erect seed is growing on each scale. Leaf cuticles are hypostomatic. Monocylic stomata are ellipse, composed of 2 sunken guard cells and 4-8 subsidiary cells. Moreover, the cuticles of a young female cone of Pityostrobus yingchengensis Yang are described for the first time.
Abundant palynological fossils are found from the drill core in the west slope of Songliao Basin, the first full coring borehole that drilled throughout the Neogene. Two Palynological assemblages are recognized according to their vertical distributions, i.e., the late early Miocene–middle Miocene assemblage from the Da'an Formation named as Caryapollenites simplex-Momipites coryloides-Celtispollenites sp.-Tsugaepollenites igniculus, and the late Miocene-early Pliocene assemblage from the Taikang Formation named as Artemisiaepollenites minor-Betulaceoipollenites sp.-Carpinipites sp.-Polypodiaceaesporites sp. On the basis of the composition of each assemblage, we infer that the climate was warm-temperate to sub-tropic during the late early Miocene–middle Miocene and the vegetation was mainly deciduous broadleaved forest and subordinate coniferous and broad-leaved mixed forest with few understory ferns, and probably some shallow fresh water wetlands. The climate then turned cooler and drier in the late Miocene–early Pliocene, represented by the development of xerophytic herbs and temperate plants, although the canopy of the forest remained relatively stable. The results significantly improve the understanding of the Cenozoic palynostratigraphy in the Songliao Basin, and provide new data for both stratigraphical correlation and paleovegetational and paleoclimatical analysis in adjacent area.
WAN ChuanBiaoSUN YueWuXUE YunFeiQIAO XiuYunJIN YuDongZHANG YiYong
Based on the palynological data from Well Ta-19-36 and Well Ta-19-37 in the Ta'nan Sag, and Well Ta-22-1 and Well Ta-21-1 in the Bayin Gobi Sag, a spore-pollen assemblage from the Damoguaihe Formation is named as Cicatricosisporites minutaestriatus- Aequitriradites spinulosus-Protopinus sp. assemblage in the Tamutsag Basin, Mongolia. The assemblage is characterized by abundant gymnosperm pollen and diverse fern spores, counted 46.35%–65.57% and 34.43%–52.58% in percentage respectively. Among the gymnosperm pollen, Pinuspollenites sp.(2.66%–16.94%), Protopinus sp.(0–11.38%) and Protopicea sp.(0–10.81%) are dominant; and Alisporites sp., Cerebropollenites sp., Podocarpidites sp., and Abietineaepollenites sp. are common. Some important elements, such as Chasmatosporites sp., Callialasporites prominulus, Parvisaccites sp., Parcisporites sp., Jiaohepollis cf. annulatus, J. bellus, J. verus, Polycingulatisporites sp., Schizaeoisporites certus, Classopollis annulatus are seen. Within the fern spores, Osmundacidites wellamanii(0.85%–4.93%), Appendicisporites sp.(0–4.45%), Baculatisporites comaumensis(0.80%–2.87%), Cicatricosisporites sp.(0.51%–2.66%), C. minor(0–2.14%), Foraminisporis asymmetricus(0–2.40%), Aequitriradites sp.(0– 2.19%) and Cyathidites minor(0–2.13%) are dominant; and some specie of Densoisporites, Cooksonites, Impardecispora, Pilosisporites, Schizaeosprites, Fixisporites, Leptolepidites, Trilobosporites, Kuylisporites, Klukisporites, Hsuisporites, Couperisporites, Maculatisporites are seen. The angiosperm pollen are rare in the assemblage, characterized by Clavatipollenites sp.(0–0.80%) and Songipollis sp.(0–0.27%). The geological age of the Damoguaihe Formation is assigned to Hauterivian – Barremian of Early Cretaceous according to the palynological data, due to the fact that there existed a lot of diverse spores of the family Schizaeaceae and prosperous gymnosperm saccat pollen which the corpus and sacci are differentiated completely, and the presence of early angiosper
Objective The Hailar Basin is situated in the northwestern margin of the Jiamusi-Mongolia Block.It was a continent marginal basin to the south of the Mongolia-Okhotsk Ocean during the Jurassic and Cretaceous.The basement of the basin is a late Paleozoic marine deposit.The filling of the basin is characterized by terrestrial volcanic rocks。
WAN ChuanbiaoXUE YunfeiSUN YuewuHOU YanpingJIN YudongZHANG XinLI Ti
This study identified two palynological assemblages,namely Bayanhuasporites-Cycadopites-Protoconiferus and Cicatricosisporites-Cedripites-Perinopollenites,in the Tongbomiao Formation in the Hongqi Sag in the Hailar Basin,Inner Mongolia,China for the first time.The former is distributed in the lower part of the Tongbomiao Formation and is characterized by abundant gymnosperm pollen and diverse fern spores.Among them,the gymnosperm pollen is dominated by Paleoconifer(4.98%-31.62%)and Cycadopite(8.55%-25.23%)pollen grains and also includes other pollen grains such as Classopollis,Parcisporites,Erlianpollis,Callialasporites,and Jiaohepollis.The fern spores in the former palynological assemblage contain Bayanhuasporite(0-8.96%),Granulatisporites(0.93%-6.97%),and some important Cretaceous genera,such as Cicatricosisporites,Concavissimisporites,Densoisporites,Hsuisporites,Foraminisporis,and Leptolepidites.The Cicatricosisporites-Cedripites-Perinopollenites palynological assemblage is distributed in the upper part of the Tongbomiao Formation.Gymnosperm(77.30%),Pinaceae(31.9%),and Paleoconiferus(19.02%)pollen predominate this palynological assemblage,and Quadraeculina,Erlianpollis,and Jiaohepollis pollen are also common in this assemblage.The fern spores in this palynological assemblage include abundant Cicatricosisporites(4.29%).Besides,Concavissimisporites,Aequitriradites,and Leptolepidites are also common in this palynological assemblage.No angiosperm pollen has been found in both palynological assemblages.The identification of both palynological assemblages provides important evidence for the biostratigraphic correlation between the Hailar Basin and its adjacent areas.It also enables the reconstructions of the Berriasian-Valanginian(Early Cretaceous)vegetation and the paleoclimate on the eastern Mongolian Plateau during 141-132 Ma.The vegetation reconstructed on the palynological data of the represented by Hailar Basin in eastern Mongolian Plateau(141.6-141.4 Ma),form conifer forest or conifer broad-leaved mixed fores
Yan ZhangYun-fei XueChun-yang BuTi LiXin ZhangYu-dong JinYue-wu Sun
