摘要
引言根据中国科学院和西德Max-Plank协会的合作课题“上白垩统,特别是白垩系-第三系交界的全球事件”的陆相部分项目,由中国科学院古脊椎动物与古人类研究所、南京地质古生物研究所和西德波恩大学古生物研究所组成的综合考察队,分别于1983和1984年9-10月,在广东南雄盆地进行野外工作。我们在南雄盆地的杨梅坑-大塘、堂田-飒门垭、百花潭-武台岗以及南雄县附近的古子坑剖面,采集了近500层孢粉样品。在大塘剖面的南雄组、上湖和罗佛寨组中获得了孢粉化石。其中南雄组中的化石孢粉极少。
In the Nanxiong basin of northern Guangdong, the Upper Cretaceous and Lower Tertiary deposits have been divided into four stratigraphical units, namely, Nanxiong Formation of Upper Cretaceous, Shanghu Formation, Lofochai Formation and Danya Formation of Lower Tertiary. So far as we know, very few spores have been recorded from the Nanxiong Formation, though sporo-pollen assemblages have been reported from the Lofochai and Danya Formations (Li Man-ying, 1983). This paper deals mainly with the sporo-pollen of the Shanghu Formation which is composed of dark purple silt-mudstone and argillaceous siltstone intercalated with greyish-green calcareous siltstone lenses.The fossil pollen grains and spores analyzed were from the beds of dark purple silt-mudstone. The average percentages of the main groups in this microflora are listed as follows: Pteridophyta 3.40％ Gymnospermae 12.10％and Angiospermae 84.12％ Among them, the pollen grains of Angiospermae are very abundant and are dominated by porate pollen grains which reach 41.6％ of the total number, mainly belonging to Ulmipollenites and Ulmoideipites. The less numerous are Alnipollenites, Engelhardtioidites, Pterocaryapollenites, Juglanspoilenites, with small amounts of Sporopollis, Plicapollis, Tiliaepollenites, Subtriporopollenites and Triporopollenites. Tricolpate pollen grains :amount to 27.2％ The high f requence of the genus Quercoidites. is notable, which is about 25.6％ of the totalnumber, whereas such genera as Salixipollenites, Striatopollis, Tricoipites and .Tricolpopollenites only account fox about 1.2％. The tricolporate pollen grains chiefly, consist of Cupuliferoipollenires, with some other genera of this group such as Callistopollenites, Syncolporites, Caprifoliiporites, Bochlensipollis, Symplocospollenites, Fraxinoipollenites and Margocolporites, accounting for 14.63％ of the total assemblage. Gymnospermous pollen grains occupy 12.10％ ofthetotal number, in which the, most common genus is Taxodiaceaepollenites, with small amounts of the genera Monosulcites, Laricoidites, Ephedripites and Abletineaepollenites. The spores of Pteridophyta are represented by Schizaeoisporites, Pterisisporites and Lygodiumsporites, but with an extremely low quantity reaching to only 3,4％ of the total number. The stratigraphical range and geographical distribution of some important forms in the assemblage are listed below: Species Age Distribution Alnipollenites fushunensis Paleocene Liaoning d. of. speciipites Paleocene Liaoning; America A. tenaipolus Paleocene Liaoning Caprfoliiporites microratus Late Cretaceous—Early Tertiary Yunnan, Guangdong Carpinipollenites spackmanii Eocene—Oligocene Jiangsu Caryapollenites triangulus Late Cretaceous—Early Tertiary Jiangsu; Europe Cupuliferoipollenites cingulum Early Tertiary Jiangsu, Guangdong C. fusus Late Cretaceous—Earfy Tertiary Jiangsu, Guangdong C. pusillus Paleocene Jiangxi Engelhardtioidites microcoryphaeus Late Cretaceous—Early Tertiary Yunnan Early Tertiary Europe Fraxinoipollenites granulatus Late Cretaceons—Earty Tertiary Yunnan Juglanspollenites verus Early Tertiary Guangdong Margocolporites elegans Early Tertiary Jiangsu Plicapollis serta Late Cretaceous—Early Tertiary Yunnan, Guangdong Pterocaryapollenites sellatus Late Cretaceous—Early Tertiary Jiangsu, Guangd0ng; Europe Quercoidites asper Late Cretaceous—Early Tertiary Jiangsu, Jiangxi, Guangdong microhenrici Late Cretaceous—Early Tertiary Jiartgsu;Europe Q. minar Eocene Jiangxi Salixipollenites. elegans Paleocene Liaonong, Early Tertiary Guangdong S. discoloripites Paleocene—Early Eocene Jiangxi S. hians Paleocene—Early Eocene Jiangxi Sporopollis fushunensis Paleocene Liaoning S. singuleris Late cretaceous Guangdong, Jiangsu; Paleocene Russia Subtriporopollenites.granulatus Late Cretaceous—Early Tertiary Yunnan, Jiangsu Species Age Distribution S.intraconstans Late Cretaceou—Earty Tertiary YUnnan; Eurrope Striatopollis microstriatus Late Cretaceous—Early Tertiary Yunnan Tiliaepollenites minimus Early Tertiary Jiangsu, Hebei Triporopollenites nointelensis Paleocene—Eocene Liaoning, Jiangxi T. palanulatus.Paleocene Liaoning Ulmipollenites granopollenites Paleocene Jiangxi U. minor Late Cretaceous—Early Tertiary 3iangsu, Jiangxi, Liaoning; Ulmoideipites krempii Paleocene Late Cretaceous—Early Tertiary America Jiangsu, Jiangxi,America, RuSsia Ephedripites (D.) zigzagus Paleocene Jiangxi Pterisisporites zonatus Late Cretaceous—Early Tertiary Yunnan As shown in the list, some genera and species denote their flourishing age in Paleocene, such as Alnipollenites tenai'polus, A. fushunensis, A. soeciipites, Cupuliferoipollenites pusillus, Triporopollenites polanulatus, Ulmipollenites granopollenites, U. minor, Sporopollis funshunensis, Ephedripites (D.) zigzagus, Carpnipollenites spackmanii, Salixipollenites elegans, S. discoloripites, Ulmoideipites krempii and Subtriporopollenires intraconstans. Other forms of the assemblage occurred in Late Cretaceous—Early Tertiary, with only a few forms appearing in the Paleocene—Eocene or Eocene. The assemblage comparable with this was obtained from the Early Paleocene deposits in the Xinfeng basin, Jiangxi. Preponderance of the Ulmipollenites, Ulmoideipites and Quercoidites is one of the common features in these two assemblages. Besides, porate grains such as Alnipollenites, Engelhardtioidites and Subtriporopollenites usually made tip the most abundant elements. Tricolporate pollen are less common in both assemblages than in those assemblages of Late Paleocene or Paleocene—Early Eocene in China, Pollen grains of Jiangsupollis, Jianghanpollis and aquilapollen are important elements of Late Cretaceous in South China or North China. However, there is no positive evidence showing the occurrence of those forms in this assemblage, indicating that this assemblage is different from the Late Cretaceous assemblages of South China and North China. The pollen grains and spores of the assemblage can be inferred as belonging to a mixed forest of evergreen broad-leaf, deciduous broad-leaf and some evergreen needleleaf trees, indicating a warm temperate to subtropic climate.
出处
《古生物学报》
CAS
CSCD
北大核心
1989年第6期741-750,828-830,共10页
Acta Palaeontologica Sinica
