Mid-Neoproterozoic protoliths of high–ultrahigh-pressure metamorphic rocks in the northeastern margin of the Yangtze Block preserve one of the best examples of ¹⁸O-depleted magmatic provinces worldwide, which is the significant record for lithospheric extension associated with continental rifting. In this contribution, we report the depleted ¹⁸O signature of felsic meta-volcanic rocks from the Zhangbaling Uplift (ZBLU), a segment of the Tan–Lu fault zone, which is located between the Dabie and Sulu orogenic belts. The low-δ¹⁸O signature of these rocks provides crucial information for understanding their origin and tectonic setting. Zircons yield UPb protolith ages of 771 ± 5 Ma to 761 ± 5 Ma and show a narrow range in δ¹⁸O values of 1.97‰ to 3.11‰. The typical syn-magmatic characteristics of these zircons indicate that they record inheritance from low-δ¹⁸O magmas during the mid-Neoproterozoic, which suggests the occurrence of high-temperature surface-water–rock interaction in a continental rift setting. Quartz keratophyres in the ZBLU exhibit A-type granite geochemical compositions with high contents of high-field-strength elements (Zr + Nb + Ce + Y > 350 ppm) and a zircon saturation temperature of 829 °C. The zircon grains have slightly depleted ε_Hf(t) values of −3.4 to +1.9, which suggest Mesoproterozoic juvenile crustal formation in response to the amalgamation of the Yangtze Block with the Rodinia supercontinent. A few coeval spilites (758 Ma) crop out sporadically in the ZBLU. Their geochemical characteristics include high SiO₂ contents (51.06–57.03 wt%), low Mg^# values (42–53), and arc-like trace-element distribution patterns. The variable zircon ε_Hf(t) values for the spilite samples can be divided into two groups: negative ε_Hf(761 Ma) values of −16.4 to −11.1, and positive ε_Hf(744 Ma) values of +5.9 to +8.5, which supports source mixing between enriched mantle and residual oceanic crustal material. In conclusion, the ZBLU spilite–keratophyre sequence is composed of a typical bimodal rock association, providing new petrological evidence for the origin of low-δ¹⁸O magmas and for a continental rift setting related to the separation of the Yangtze Block from the Rodinia supercontinent at ca. 771 Ma.

扬子地块东北缘的中新元古代高变质原岩保留了全世界^18个O耗竭岩浆省的最佳实例之一，这是与大陆裂谷有关的岩石圈扩张的重要记录。在这项贡献中，我们报告了位于大别山和苏鲁造山带之间的Tan庐断裂带的一段张巴岭隆起（ZBLU）的长英质火山岩的¹⁸ O特征。低δ ¹⁸ Ø这些岩石的签名为了解它们的起源和构造环境的关键信息。锆石得到ü的771±5马铅原岩年龄至761±5 Ma和显示δ窄幅¹⁸O值为1.97‰至3.11‰。典型的顺这些锆石-magmatic特性表明它们从低δ记录继承^18个在新元古代中期，这表明高温表面水岩相互作用在大陆裂谷设置发生Ò岩浆。ZBLU中的石英角膜岩显示出A型花岗岩地球化学成分，其中高含量的高场强元素（Zr + Nb + Ce + Y> 350 ppm）和锆石饱和温度为829°C。锆石颗粒略有耗尽ε_铪（t）值介于-3.4到+1.9之间，这表明中子生代幼体地壳是响应于扬子地块与罗丹尼亚超大陆的合并而形成的。ZBLU中偶尔散生出一些同时代的早霞石（758 Ma）。它们的地球化学特征包括高SiO ₂含量（51.06–57.03 wt％），低Mg ^＃值（42–53）和弧状痕量元素分布模式。可变锆ε_的Hf（t）值的细碧样品可以被分成两组：负ε_的Hf的-16.4（761 Ma）的值-11.1，和正ε_铪（744 Ma）值在+5.9到+8.5之间，这支持了富集地幔与残余海洋地壳物质之间的源混合。总之，ZBLU细碧-角斑岩序列由典型的双峰岩石组合，低δ起源提供了新的岩石学的证据^18个Ø岩浆和相关扬子陆块从Rodinia超分离大陆裂谷环境在约。771马。