龙门山地区中泥盆统养马坝组风暴沉积中的遗迹化石及其环境意义  

Ichnofossils and Their Environmental Significance in Storm Deposit from the Middle Devonian Yangmaba Formation in Longmenshan Area

作　　者：荆锡贵 陈政安 李凤杰[2] 文胜男 谢胜军 JING XiGui;CHEN ZhengAn;LI FengJie;WEN ShengNan;XIE ShengJun(Siping Oil Production Plant of Northeast Oil & Gas Company,SINOPEC,Changchun 130062,China;Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,China;Wenliu Oil Production Plant of Zhongyuan Oilfield Company,SINOPEC,Puyang,Henan 457171,China)

机构地区：[1]中国石油化工股份有限公司东北油气分公司四平采油厂,长春130062 [2]成都理工大学沉积地质研究院,成都610059 [3]中国石油化工股份有限公司中原油田分公司文留采油厂,河南濮阳457171

出　　处：《沉积学报》2019年第4期749-757,共9页Acta Sedimentologica Sinica

基　　金：国家自然科学基金项目（41172100）;四川省教育厅自然科学重点项目（12ZA012）;成都理工大学沉积地质学创新团队基金（KYTD201703）~~

摘　　要：龙门山地区泥盆纪地层中含有种类丰富、数量众多的海相遗迹化石。以野外剖面实测为基础,对北川甘溪石沟里剖面中泥盆统养马坝组风暴沉积中的遗迹化石进行了系统描述,共识别出5种类型的遗迹化石属种,包括Chondrite、Changchengia、Rhizocorallium、Skolithos和Zoophycos。根据遗迹化石的组合特征,将其划分为Chondrites-Zoophycos遗迹化石组合类型,反映了受风暴影响的浅水沉积环境。通过遗迹化石的分布位置、相互间的切割关系,建立了龙门山地区石沟里剖面养马坝组风暴岩中各种遗迹化石形成的先后顺序,依次为Chondrites、Zoophycos、Rhizocorallium、Changchengia和Skolithos。发育于风暴岩中的Chondrites和Zoophycos遗迹化石,具有鲜明的机会种特征,对沉积环境有重要的指示意义。保存于龙门山地区泥盆系养马坝组风暴岩中丰富的具细小分支直径的Chondrites遗迹化石,反应水体氧含量并非控制Chondrites潜穴直径大小的唯一控制因素,可能与造迹生物生活环境的恶劣与否间存在着一定关系;风暴沉积中发育的Zoophycos遗迹化石,指示其在泥盆纪可以沉积于浅海环境。Abundant marine trace fossils are preserved in Devonian strata in the Longmenshan area. Geological investigation of the Shigouli outcrop in the Jiangyou area found trace fossils preserved in tempestite from the upper Yangmaba Formation,and are systematically described. A total of five ichnogenera were identified:Chondrites,Changchengia,Rhizocorallium,Skolithos and Zoophycos. Of these,Chondrites-Zoophycos ichnofacies reflect a shallow shelf environment affected by storm action. The order in which the trace fossils appeared was identified from the cross-cutting relationship between the traces and their positions:Chondrites,Zoophycos,Rhizocorallium,Changchengia and Skolithos. The Chondrites and Zoophycos ichnofossils in the tempestite had the distinctive features of opportunistic species,and are important indicators of the sedimentary environment. Numerous thick branched Chondrite burrows reflect the oxygen content of the water at that time. This not only controlled the burrow diameter,it may also imply a link between burrow diameter and the severity of the living environment. The Zoophycos in the tempestite revealed that its trace maker was living in shallow shelf deposits in the Devonian.

关 键 词：龙门山地区 泥盆纪 遗迹化石 古环境 

分 类 号：Q911.28[天文地球—古生物学与地层学]