丹麦哥本哈根大学Andreas Petersson团队在研究Fennoscandian地盾的太古代地壳核与北大西洋克拉通的联系中取得进展。相关论文于2023年12月28日发表于国际顶尖学术期刊《地质学》杂志上。
研究人员展示了来自芬兰三条主要河流的碎屑锆石的U-Pb、O和Hf同位素数据，以及来自芬兰中部太古带Suomujrvi和Pudasjrvi杂岩的早期岩石的锆石O和Hf同位素数据。综合来看，这些数据证明在Fennoscandian地盾中，存在一个以前未被识别的ca.3.75 Ga的地壳核。
该成果强调了这些核对大陆地壳生长的重要性，促进了研究人员在全球各地太古代地体中识别出的越来越多的太古宙核。Fennoscandian地核的同位素特征与格陵兰的等年龄岩石相对应，并与Fennoscandia和北大西洋克拉通共同的太古代演化相一致。
据悉，促进大陆地壳的形成是稳定克拉通岩石圈的重要步骤。然而，这些初始的地壳核要么被再循环破坏，要么被较新的岩石掩埋。在Fennoscandian地盾中，最古老的岩石地质年龄约为ca. 3.5 Ga，但继承的（约ca.3.7 Ga）和岩屑中的锆石表明，存在一个更古老、且未暴露的地壳基底。
附：英文原文
Title: An Eoarchean continental nucleus for the Fennoscandian Shield and a link to the North Atlantic craton
Author: Andreas Petersson, Tod Waight, Anthony I.S. Kemp, Martin. J. Whitehouse, John W. Valley
Issue&Volume: 2023-12-28
Abstract: Enabling the build-up of continental crust is a vital step in the stabilization of cratonic lithosphere. However, these initial crustal nuclei are commonly either destroyed by recycling or buried by younger rocks. In the Fennoscandian Shield, the oldest rocks are ca. 3.5 Ga, but ca. 3.7 Ga inherited and detrital zircons suggest the presence of an older, unexposed crustal substrate. We present U-Pb, O, and Hf isotope data from detrital zircons of three major Finnish rivers as well as zircon O and Hf isotope data from previously dated rocks of the Archean Suomujrvi and Pudasjrvi complexes, central Finland. Combined, these data indicate a previously unidentified ca. 3.75 Ga crustal nucleus in the Fennoscandian Shield. This adds to the growing number of Eoarchean nuclei recognized in Archean terranes around the globe, highlighting the importance of such nuclei in enabling the growth of continental crust. The isotope signatures of the Fennoscandian nucleus correlate with equivalent-aged rocks in Greenland, consistent with a common Eoarchean evolution for Fennoscandia and the North Atlantic craton.
DOI: 10.1130/G51658.1
Geology：《地质学》，创刊于1973年。隶属于美国地质学会，最新IF：6.324
官方网址：https://pubs.geoscienceworld.org/geology
投稿链接：https://geology.msubmit.net/cgi-bin/main.plex