Late Mesozoic magmatism at Xiaokelehe Cu Mo deposit in Great Xing'an Range, NE China: Geodynamic and metallogenic implications

Petrogenesis and Tectonic Setting of Early Cretaceous Intrusive Rocks in the Northern Ulanhot Area, Central and Southern Great Xing’an Range, NE China

“…In terms of the regional structure, the Tayuan-Xiguitu fault zone, Heihe-Hegenshan fault zone, and Yilan-Yitong fault zone indicate the boundaries of these blocks from northwest to southeast [6,18,40,67,68], and the Solonker-Xar Moron suture zone marks the final collage demarcation line between the North China Craton and the blocks of NE China during the Late Permian-Middle Triassic period [17,35,69,70]. Since the Mesozoic era, NE China has experienced multi-stage structural superposition and tectonic reformation of the PPO and Mongol-Okhotsk Ocean tectonic domains, forming extensive Mesozoic volcanic and granitic rocks (Figure 1c) [16,17,26,43,53,71] and constraining the patterns of crustal growth and crust-mantle interaction in this region [7,24,25,32,63,72]. With the development of research, the subduction of the Mongol-Okhotsk Ocean plate dated from the early Mesozoic [45,73,74], and this paleo-ocean closed in a scissor-like mode from west to east and eventually disappeared in the Amur region in the Late Jurassic [55,74].…”

“…From the point of view of plate tectonics, NE China belongs to the eastern section of the Central Asian Orogenic Belt (Figure 1a) [4][5][6]8,9,18,24,39,63] and is confined between the Solonker-Xar Moron suture zone on the northern margin of the North China Craton and the Mongol Okhotsk suture zone on the southern margin of the Siberia Craton, with the western Pacific coastal zone to the east (Figure 1b) [7,[10][11][12][13]16,17,19,20,32,53,65]. The main body of NE China is actually composed of Erguna, Xing'an, Songnen, and Jiamusi block systems, interspersed with a series of microcontinental masses, which correspond to subduction and closure of the events in the Paleo-Asian Ocean during the Palaeozoic to Early Mesozoic eras [25,26,29,35,66]. In terms of the regional structure, the Tayuan-Xiguitu fault zone, Heihe-Hegenshan fault zone, and Yilan-Yitong fault zone indicate the boundaries of these blocks from northwest to southeast [6,18,40,67,68], and the Solonker-Xar Moron suture zone marks the final collage demarcation line between the North China Craton and the blocks of NE China during the Late Permian-Middle Triassic period [17,35,69,70].…”

“…Previous studies have shown that the tectonic magmatic activities from the Paleozoic to the Mesozoic in the GXR were frequent and complex [55,72], especially marked by the large-scale outcropping of Late Mesozoic granitic rocks (Figure 1c) [8,18,26,38,71,[105][106][107]. Numerous geochronological data indicate that the magmatic activities in the GXR area reached a peak during the Early Cretaceous, with the formation age of the granitic rocks ranging from 140 to 125 Ma (Supplementary Table S4; Figure 8) [2,14,19,23,108].…”

“…Numerous geochronological data indicate that the magmatic activities in the GXR area reached a peak during the Early Cretaceous, with the formation age of the granitic rocks ranging from 140 to 125 Ma (Supplementary Table S4; Figure 8) [2,14,19,23,108]. However, these studies were mainly focused on the northern and southern parts of the GXR [5][6][7]20,24,26,32,34,35,57,63] and few have focused on the central-southern segment (1,16,17,64). In this study, we selected intrusive rock samples (DBT01, DBT02, XLT01, and SQT01) from the northern Ulanhot area in the central-southern GXR for the first time to conduct high-precision zircon U-Pb age testing (Figure 2), and it was concluded that the crystallization ages of these rocks were approximately 128-124 Ma (Figure 4).…”

“…Northeast (NE) China, which is well-known for its extensive distribution of Late Mesozoic igneous rocks [1][2][3][4][5][6][7][8], is situated in the eastern segment of the Central Asian Orogenic Belt and bounded by the northern part of the North China Craton, the southern part of the Siberia Craton and the western Pacific rim (Figure 1a) [9][10][11][12][13][14][15][16][17][18][19][20]. During the Late Mesozoic, this region experienced multi-stage structural superposition and tectonic reformation of the Paleo-Pacific Ocean (PPO) and Mongol-Okhotsk Ocean tectonic domains, recording multiple tectonic-thermal events of different scales by widespread intrusive rocks [13,[21][22][23][24][25][26][27]. It has been a hot area for the interpretation of mantle-crust interactions and crustal evolution over the past two decades and an important metallogenic belt (Figure 1b) [28][29][30][31][32][33][34][35].…”