加拿大滑铁卢大学Qǐháng Wú研究团队取得一项新突破。他们报道了基于碎屑伴生矿物U-Pb年代学和微量元素地球化学的，同造山盆地缺失源造山带的识别与表征。相关论文于2024年4月18日发表于国际顶尖学术期刊《地质学》杂志上。

在超大陆分散碎片中确定同造山带沉积物的造山带，为研究超大陆组合过程中造山带的构造演化和古地理重建提供了重要信息。以锆石、金红石、磷灰石、独居石等多种碎屑矿物的U-Pb年代学和微量元素为主题的研究方法，比单独研究碎屑锆石具有重要的优势。研究表明，这些岩石沉积在两个不同但重叠的同造山盆地中，这些同造山盆地与东冈瓦纳组合有关。

埃迪卡拉系岩石的碎屑可能来自澳大利亚的帕特森-彼得曼造山带(PPO)，而占主导地位的650碎屑金红石和磷灰石的600 Ma种群和微量元素组成表明，造山带发生了一次重要的埃迪卡拉纪热高压变质事件。寒武系和冬系岩石中金红石和磷灰石碎屑群的出现表明，寒武系造山带起源于一个具有多热事件特征的不同强度造山带，最有可能是Kuunga-Pinjarra造山带(KPO)。

他们的数据表明，西华夏古陆位于PPO和KPO附近，并支持PPO是一个碰撞的假设，而不是一个长期存在的后格伦维利亚板内造山带。他们的数据还表明，保存较差的KPO北部地区和更大范围的大印度地区存在多变质历史。

附：英文原文

Title: Identifying and characterizing missing source orogens for syn-orogenic basins based on detrital accessory mineral U-Pb geochronology and trace element geochemistry

Author: Lijun Wang, Shoufa Lin, Wenjiao Xiao, John M. Hanchar, William J. Collins, Donald W. Davis, Chris Yakymchuk, Guangfu Xing, Zhijun Niu, Dunfeng Xiang, Cees R. van Staal, Qǐháng Wú

Issue&Volume: 2024-04-18

Abstract: Identifying source orogens for syn-orogenic sediments in dispersed fragments of a supercontinent provides key information on the tectonic evolution of the orogens involved in supercontinent assembly and on paleogeographic reconstruction. An approach using U-Pb geochronology and trace elements of multiple detrital minerals including zircon, rutile, apatite, and monazite has major advantages over detrital zircon studies alone. Application of this multi-pronged approach to Ediacaran and Cambrian clastic sedimentary rocks from the West Cathaysia terrane of the South China block demonstrates that these rocks were deposited in two distinct, but overlapping, syn-orogenic basins related to the assembly of eastern Gondwana. The Ediacaran rocks have detritus likely sourced from the Paterson-Petermann orogen (PPO) in Australia, and the dominant 650600 Ma populations and trace element compositions of detrital rutile and apatite indicate a significant Ediacaran thermal and high-pressure metamorphic event in the orogen. The appearance of Cambrian and Tonian detrital rutile and apatite populations in the Cambrian rocks indicates derivation from a different source orogen characterized by multiple thermal events, most likely the Kuunga-Pinjarra orogen (KPO). Our data suggest that West Cathaysia was located adjacent to both the PPO and the KPO and support the hypothesis that the PPO was a collisional, rather than a long-lived post-Grenvillian intraplate, orogen. Our data also suggest a poly-metamorphic history for the poorly preserved northern part of the KPO and a larger expanse of Greater India.

DOI: 10.1130/G52212.1

Source: https://pubs.geoscienceworld.org/gsa/geology/article/doi/10.1130/G52212.1/638411/Identifying-and-characterizing-missing-source