天山哈密翼龙化石围岩风化机理初步分析  

THE WEATHERING MECHANISM OF SURROUNDING ROCKS IN HAMIPTERUSFOSSIL

作　　者：李颖 罗武干[1,2] 杨益民 汪筱林[1,3] LI Ying;LUO Wu-gan;YANG Yi-min;WANG Xiao-lin(Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences,Institute of Vertebrate Paleontology and Paleoanthropology,Chinese Academy of Sciences,Beijing100044,China;Department of Archaeology and Anthropology,University of Chinese Academy of Sciences,Beijing100049,China;College of Earth and Planetary Sciences,Beijing100049,China)

机构地区：[1]中国科学院古脊椎动物与古人类研究所脊椎动物演化与人类起源重点实验室,北京100044 [2]中国科学院大学考古学与人类学系,北京100049 [3]中国科学院大学地球与行星学院,北京100049

出　　处：《古生物学报》2019年第4期515-525,共11页Acta Palaeontologica Sinica

基　　金：国家自然科学基金(41572020,41688103);中国科学院大学校所科研合作课题(Y65201WY00);哈密市政府合作项目资助。

摘　　要：哈密翼龙及其3D蛋与胚胎化石的发现,具有重要的科学价值。然而,这些化石在离开原始埋藏环境之后,就会出现粉化剥落等严重自然风化现象。本文拟利用XRF等多种方法对代表性化石的赋存围岩样品进行分析检测,以探讨其风化破碎机理。分析表明,化石围岩为含泥砾的砂岩,含有蒙脱石等黏土类矿物,胶结物为钙质和盐类,且围岩中含有大量的Cl-、NO3-、Na+和Mg2+等可溶盐。因此,本文指出围岩产生风化的主要机制是当湿度发生变化时,盐胶结溶解,同时围岩中的可溶盐溶解重结晶产生的巨大结晶压力,以及蒙脱石等矿物吸水膨胀产生巨大的挤压力,促使围岩在巨大内部应力等综合作用下逐渐粉化脱落,最终导致围岩彻底破碎。基于以上认识,也给出了化石的保护建议。The value of the discoveries of Hamipterus tianshanensis and their 3D egg fossils are of great importance.These fossils have been preserved in Beijing for several years,the surrounding rocks have been powdering and flaking,which seriously endangers the safety of fossils.This paper intends to explore the corrosion mechanism of the surrounding rock of fossils by means of XRF and other methods. The analysis shows that the surrounding rock of fossils is composed of sandstone with boulder clay,which contains some clay minerals such as montmorillonite. The sandstone with calcareous and salt cementation contains large amounts of soluble ions such as Cl-,NO3-,Na+ and Mg2+.The mechanism of the deterioration is as followed,when the humidity changes,the soluble salt generates large crystal pressure,as well as the expansion of clay minerals produces huge pressing force, leading the surrounding rocks to powder and flake gradually.The solution of salt existing as the cement results in the escape and migration of particles,which is an important reason for fossil deterioration.Based on the above understanding,this paper also gives suggestions about the protection of fossils.

关 键 词：天山哈密翼龙 化石围岩 风化机理 化石病害 化石保护 

分 类 号：Q911.2[天文地球—古生物学与地层学]