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综述了近年来国际上在 Sr同位素研究应用方面的新成果 ,着重讨论了如何应用海相沉积岩 (物 ) 87Sr/ 86Sr比值来研究海平面变化和全球对比问题。综合分析表明 ,海水 Sr同位素组成受 Sr的来源控制 ,海水87Sr/ 86Sr比值随时间变化与海平面变化有内在的联系 ,高频旋回 (时限约 2 .0Ma)的87Sr/ 86Sr变化与三级海平面变化相对应。研究认为牙形石是分析 Sr同位素组成最理想的样品 ,用之建立的 87Sr/ 86Sr变化曲线最具全球对比意义。与国外相比 ,我国在这方面研究成果较少 ,但从地质条件分析 ,我国独有的一些地质记录 ,在古海平面变化和全球对比研究中占据着不可缺少或不可代替的地位 ,其中扬子地块西南缘二叠—三叠纪界限附近的 87Sr/ 86Sr变化曲线 ,可以弥补国外一些学者建立的自显生宙以来全球海水87Sr/ 86Sr变化曲线在该时段存在的“断层”现象。
In this paper, the recent achievements in the application of Sr isotopes in the world are reviewed. The application of the 87Sr / 86Sr ratios of marine sediments to the study of sea level changes and global comparisons are discussed. Comprehensive analysis shows that the Sr isotope composition of seawater is controlled by the source of Sr. The 87Sr / 86Sr ratio of 87Sr / 86Sr ratio changes with time and sea level is intrinsically linked with the sea level change. The 87Sr / 86Sr variation of high frequency cycle (time limit of about 2.0Ma) Corresponds to changes in the plane. The study shows that conodont is the most ideal sample for analyzing the composition of Sr isotopes, and the 87Sr / 86Sr curve established by it is the most globally significant. Compared with other countries, our country has less research results in this respect. However, from the analysis of geological conditions, some geological records unique to our country occupy an indispensable or irreplaceable position in the study of the change of the ancient sea level and the global comparative study. Among them, The 87Sr / 86Sr curve near the Permian-Triassic boundary in the southwestern margin of the block can make up for the “fault” phenomenon of 87Sr / 86Sr curves of global seawater 87Sr / 86Sr developed by some scholars abroad since the Phanerozoic.