抚顺盆地东露天煤矿早始新世孢粉组合特征及其古气候意义

系统研究了抚顺盆地东露天煤矿主煤层古城子组植物孢粉组合特征,并采用共存分析法(coexistence approach)定量分析了该区早始新世古气候。笔者在古城子组共发现孢粉化石71属159种,其中,被子植物花粉莫米粉(Momipites)、山核桃粉(Caryapollenites)、榆粉(Ulmipollenits)和栎粉(Quercoidites)含量较高;裸子植物花粉含量高,以杉粉(Taxodiaceaepollenites)和无口器粉(Inaperturopollenites)占绝对优势;蕨类植物孢子以水龙骨单缝孢(Polypodiaceaesporites)及紫萁孢(Osmundacidites)为主。亚热带类群丰富且花粉含量较高(56.3%~91.8%)。孢粉组合反映了该盆地分布以杉科(Taxodiaceae)丰富为特征的沼泽湿地林,可能为重要的成煤植物;盆地低山地带分布有常绿和阔叶落叶混交林为主的森林植被。通过共存分析法获得抚顺盆地早始新世年均温为14.9℃~15.8℃,年均降水量为1011.3~1163 mm。孢粉植物群特征及古气候参数综合分析,抚顺盆地早始新世属于温暖湿润的亚热带气候。

Early Eocene palynological assemblages from Donglutian Coal Mine in Fushun Basin and their paleoclimatic significance

This research systematically studies the palynoflora of the Guchengzi Formation,the main coal-bearing formation in the Donglutian CoalMine(East Open-Cut Coal-Mine)in Fushun Basin,and quantitatively analyzes the climate in the Early Eocene using method of coexistence approach.71 genera and 159 species are identified in the Guchengzi Formation,in which the angiosperm pollen Momipites,Caryapollenites,Ulmipollenites and Quercoidites are abundant,gymnosperm pollen are also higher in contents with overwhelming predominance of Taxodiaceaepollenites and Inaperturopollenites;while the fern spores,Polypodiaceaesporites and Osmundacidites.The subtropical taxa are abundant and high in contents(56.3%~91.8%).The palynological assemblages show that the distribution around the basin of swamp wetland forests is characterized by Taxodiaceae which may be the important coal-forming plants,and the forest vegetation is dominated by a mixture of evergreen and deciduous broad-leaved forest in uplands of the basin.Through the coexistence approach,the average annual temperature of the Early Eocene in the Fushun Basin is 14.9℃~15.8℃and the average annual precipitation is 1011.3~1163 mm.Based on the characteristics of sporopollen flora and quantitative analysis of paleoclimate parameters,the Early Eocene climate in Fushun Basin belongs to the subtropical warm and humid climate in nature.