晋北中新世汉诺坝玄武岩中木化石的发现及其古气候意义  

The discovery of fossil woods in Miocene Hannuoba basalt in northern Shanxi Province and its paleoclimate significance

作　　者：董黎阳 王瑾 郝思宇 吕波 DONG Liyang;WANG Jin;HAO Siyu;LüBo(Shanxi Museum of Geology,Taiyuan 030021,Shanxi,China)

机构地区：[1]山西地质博物馆,山西太原030021

出　　处：《地质通报》2018年第10期1820-1824,共5页Geological Bulletin of China

基　　金：山西省国土资源厅项目<山西晚古生代锯齿龙类脊椎动物化石与地层系统调查>

摘　　要：首次在晋北中新统汉诺坝玄武岩沉积夹层中发现了木化石。通过木化石的沉积环境分析,认为其为洪积扇上发育的辫状河道环境。对树木高度进行了估算,结果表明其为中等高大的乔木。结合前人对中新世中国北方孢粉、古植物、哺乳动物化石等的分析认为,中中新世晋北左云一带处于湿润的森林,且已向较干旱的疏林草原环境过渡,季节性降水导致的洪水携带大量砂砾将平缓地带的乔木迅速埋藏。这一发现,对于研究中新世时中国北方古气候变化及植物地理区系演化具有重要意义。Fossil woods were discovered recently in sedimentary intercalation in Miocene Hannuoba basalt in northern Shanxi Prov?ince.Primary analysis indicates that the sedimentary environment of these fossil woods belonged to braided channels developed on proluvial fan,and the estimation of tree heights shows that they belongs to averagely tall arbor.Combined with palynological assem?blage,paleobotany and mammal fossils,the authors inferred a landscape of moist forest with trend of transition to arid sparse forest steppe,in which sand-gravel mixtures were rapidly carried to lowland by floods caused by seasonal precipitation,and hence these ar?bors were buried and petrified rapidly.

关 键 词：左云 汉诺坝玄武岩 木化石 古气候 

分 类 号：P534.621[天文地球—古生物学与地层学] P588.145[天文地球—地质学]