华南玻璃陨石的原生层位及其事件地层学意义

华南大玻璃陨石分布于广西、广东和海南。根据广东西部和海南岛实测的两类含玻璃陨石的地层剖面——第四系北海组与湛江组界线附近的连续剖面和与湛江组顶部剥蚀面相当的原始台地剖面。玻璃陨石从产状来看可分为埋藏的原生撒落型、暴露的原生撒落型和次生搬运型等几类,赋存的原生层位是北海组中-下部的组内剥蚀面,而不是北海组与湛江组的界面;发现了玻璃陨石及其层位附近的某些元素异常以及早更新世晚期-中更新世早期存在的环境事件与灾变,指出将华南玻璃陨石事件与华北黄土和南海深海盆沉积中的微玻璃陨石进行准确地层对比的必要性,并从玻璃陨石的研究中引入事件地层学及其与全球变化关联研究的新思路。谨以此文深切悼念我国第四纪地质及第四纪冰川地质的优秀科学家吴锡浩先生。 

INITIAL STRATA OCCURRENCE OF THE SOUTH CHINA TEKTITE IN STRATA AND ITS IMPLICATION FOR EVENT-STRATIGRAPHY

The South China tektite,especially a type of big tektite,is solely found in Chinese continent at the early time,belonging to Asia-Australia strowed area. The tektites were distributed in the areas of Guangxi, Guangdong and Hainan Provinces. According to the investigations in two types of the stratigraphic profiles, which are the boundary section of Beihai Formation and Zhanjiang Formation and the section of weathering crust on the 3rd tableland, it is suggested that there are three type of big tektites in South China continent, which are imbeded-initial-strowed type,exposed-initial-strowed type and deuterogenic moved-type;the initial occurrence of the South China tektite in strata is in the middle horizon within Beihai Formation, which is the erosion surface on the top of the lower part of Beihai Formation, but not on the top of Zhanjiang Formation. The chemical compositions, average grain size and the palynology characteristics indicate that a seriesd of geological events occurred in the period of 0.1~0.8 MaBP, so that the tektite event and its initial stratum are a good time scale for the correlation of marine and continental event-stratigraphy as well as the global geodynamics. This paper is in memory of Prof. Wu Xihao who was an excellent scientist in the field of Neozoic geology.