鄂东武汉地区志留纪红层的发现及其地质意义  

Discovery of the Silurian Red Beds and Its Geological Significance in Wuhan area, Eastern Hubei

作　　者：纵瑞文 刘一龙 尹家一 黄烈斌 ZONG Rui-Wen;LIU Yi-Long;YIN Jia-Yi;HUANG Lie-Bin(State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences,Wuhan 430074,China;School of Earth Sciences,China University of Geosciences,Wuhan 430074,China;Faculty of Land and Resources Engineering,Kunming University of Science and Technology,Kunming 650000,China)

机构地区：[1]中国地质大学(武汉)生物地质与环境地质国家重点实验室,武汉430074 [2]中国地质大学(武汉)地球科学学院,武汉430074 [3]昆明理工大学国土资源工程学院,昆明650000

出　　处：《华南地质》2022年第1期110-119,共10页South China Geology

基　　金：国家自然科学基金项目(42072041)

摘　　要：鄂东地区的志留纪地层为一套碎屑岩相沉积,因出露不佳且化石稀少,研究程度较低。本文报道了近期在武汉东部原划为“坟头组”的地层中新识别出来的一套紫红、红褐色夹少量黄绿色的碎屑岩组合,并将其厘定为清水组,相当于扬子地区的“下红层”,根据该组中新发现的三叶虫、腕足类、棘皮类和鱼类等化石,其时代相当于埃隆中晚期至特列奇早期。武汉地区清水组的发现说明了扬子地区的“下红层”在某些区域埃隆期就已沉积,即“下红层”的底界具有明显的穿时性,从埃隆中晚期穿时至特列奇早期。结合古流向和古地理分析,清水组下部的物源主要来自于东部,至上部才与扬子其他地区的“下红层”一样来自于南部的华夏古陆,物源区的不同可能也是造成武汉地区“下红层”底界明显低于其他地区的主要原因。The Silurian strata is mainly composed of clastic rocks in eastern Hubei,which is poorly studied due to poor outcrops and rare fossils.A newly identified set of purplish red,reddish brown with a few yellowish green clastic rocks assemblage in eastern Wuhan,which was classified as the Fentou Formation previously,was redivided as the Qingshui Formation,equivalent to the“Lower Red Beds”in the Yangtze region.And its age was limited to the middle-late Aeronian to early Telychian characterized by the newly found trilobites,brachiopods,echinoderms,and fish fossils from the Formation.The discovery of Qingshui Formation in Wuhan indicates that the“Lower Red Beds”was deposited during the Aeronian in some areas of Yangtze region,that is,the lower boundary of the“Lower Red Beds”is likely diachronous,ranging from the middle–late Aeronian to the early Telychian.Based on the analysis of paleocurrent and paleogeography,the provenance of the lower part of Qingshui Formation is mainly from the east,while that of the upper part is from Cathaysian Oldland in the south,just like the“Lower Red Beds”in other areas of Yangtze region.The difference source area may prove that the bottom of“Lower Red Beds”in Wuhan area is obviously lower than that in other areas.

关 键 词：清水组 下红层 埃隆阶 特列奇阶 志留系 穿时性 鄂东 

分 类 号：P534.43[天文地球—古生物学与地层学]