微区X射线荧光技术揭示宏体化石骨骼以及埋藏环境元素特征——以中三叠世盘县混鱼龙为例  

Micro X-Ray Fluorescence Technology Reveals Macrofossil Bones and Surrounding Matrix Element Characteristics——A Case Study of the Middle Triassic Mixosaurus panxianensis

作　　者：王一诺 付宛璐[1,2] 周敏 鲁昊[3] 孙作玉 姚明涛[1] 江大勇 WANG Yi-nuo;FU Wan-lu;ZHOU Min;LU Hao;SUN Zuo-yu;YAO Ming-tao;JIANG Da-yong(Department of Geology and Geological Museum,Peking University,Beijing 100871,China;State Key Laboratory of Palaeobiology and Stratigraphy(Nangjing Institute of Geology and Palaeontology,Chinese Academy of Sciences),Nangjing 210008,China;School of History,Beijing Normal University,Beijing 100875,China)

机构地区：[1]北京大学地球与空间科学学院与地质博物馆,北京100871 [2]现代古生物学和地层学国家重点实验室(中国科学院南京地质古生物研究所),江苏南京210008 [3]北京师范大学历史学院,北京100875

出　　处：《光谱学与光谱分析》2024年第7期1974-1981,共8页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(41920104001,41572008);现代古生物学和地层学国家重点实验室(中国科学院南京地质古生物研究所)(213102);安徽省自然资源厅科技项目(2021-k-13);安徽省公益性地质工作项目(2021-g-2-16)资助。

摘　　要：应用可对脊椎动物骨骼化石及其围岩元素特征进行原位无损检测的微区X射线荧光技术(Micro-XRF)对距今约2.44亿年的中三叠世海生爬行动物盘县混鱼龙(Mixosaurus panxianensis)正模及副模化石标本进行扫描,将获取的整体元素分布模式可视化,并以手持式X荧光光谱仪对部分相关特征区域进行辅助扫描。扫描结果显示,骨骼化石与围岩的元素分布呈现明显差异,骨骼化石以Ca、P、Sr、Y等元素富集为代表;围岩以Ca、K、Fe、Mn等为特征元素。此外,Zn在副模标本中呈现差异分布,躯干部位Zn富集,高于头骨。研究认为Micro-XRF扫描结果可详细揭示盘县混鱼龙的骨骼解剖学特征,补充了在一般光学显微镜下无法从化石上看到的右前肢及腹膜肋等重要信息,并可以更好地区分钙质围岩和骨骼。同时,经海陆对比,发现埋藏环境对不同元素的分布特征具有一定程度的影响,部分元素如Th、Ce、Cu、Sr表现出对埋藏环境的响应,而与骨骼相关的部分元素如Ca、P、Y受埋藏环境影响较小。另外,Zn在骨骼化石不同部位的差异分布很可能受骨骼发育影响,在副模化石标本上Zn富集的椎体及肋骨可能处于快速骨化阶段,推断该个体可能为亚成年个体。We apply the Micro-XRF,which can be used to in situ non-destructively study the element distribution of the skeleton and surrounding matrix in vertebrate fossils to scan the holotype and paratype of the Middle Triassicmarine reptile Mixosauruspanxianensis(~244 Ma),visualizing the overall element distribution of the specimens.Additionally,the paratype's regions of interest are tested using a handheld X-ray fluorescence spectrometer as an adjunct.The research results show that the bone and matrix elements present a different distribution pattern.The skeleton clearly controls Ca,P,Sr and Y.The matrix where the fossil is preserved is rich in Ca,K,Fe,and Mn.In addition,Zn is variouslydistributed in different fossil bone parts of the paratype specimen,where the Zn content is higher in the trunk region than in the skull.In terms of fossil morphology,the maps clearly resolve the fossil morphology.The right forelimb and gastralium of the paratype specimen,which are invisible in regular light,are particularly well-resolved by the elemental maps.At the same time,the calcareous matrix and bone can be distinguished better.In taphonomy,comparing the elemental features of fossilized marine and terrestrial fossils demonstrates how the burial environment affects the distribution characteristics of certain elements.Th,Ce,Cu and Sr responded to the burial environment,while some elements related to bone,such as Ca,P,and Y,were less affected by the burial environment.The distribution of Zn in different bone regions was altered by bone development,and the paratype specimen's centrums and ribs,where Zn is elevated,are likely to be in the stage of rapid ossification,indicating that the paratype specimen was subadult.

关 键 词：微区X射线荧光 盘县混鱼龙 化石 围岩 元素分布 

分 类 号：Q915[天文地球—古生物学与地层学]