Junpeng Wang, Yunzhe Jiao, Kang Jiang, Timothy Kusky, Lu Wang, Hao Deng

School of Earth Sciences, State Key Laboratory of Geological Processes and Mineral Resources, Center for Global Tectonics, China University of Geosciences, Wuhan, China

Tectono-thermal records older than ca. 1.8 Ga in the North China craton have been poorly resolved given that they have been strongly overprinted by younger events, despite being key to understanding the tectonic evolution of the craton. We report results of monazite Th–U–Pb isochron geochronology via electron probe microanalysis on the Zanhuang massif in the North China craton, to determine its detailed Precambrian tectono-thermal history. Results suggest that the ca. 2.1 Ga tectonothermal event can be divided into distinct ca. 2.17 Ga and ca. 2.10 Ga stages, reflecting metamorphism related to retroarc regional extension of the North China craton. Similarly, the previously established ca. 1.8 Ga metamorphic event can be divided into distinct ca. 1.88 Ga and ca. 1.79 Ma stages. Through a detailed summary and comparison, we interpret that the ca. 1.88 Ga monazite age reflects the timing of peak metamorphism, which was followed by ca. 1.79 Ga retrogression.

Original source: Wang J P, Jiao, Y.Z., Jiang, K., Kusky, T., Wang, L., Deng, H. Two Paleoproterozoic tectono- thermal events in the Central Orogenic belt, North China craton, determined from EPMA Th– U– Pb monazite geochronology of the Zanhuang massif. Terra Nova. 2023; 00: 1-18. https://doi.org/10.1111/ter.12680