Geochronology and geochemistry of the Late Jurassic bimodal volcanic rocks from Hailisen area, central‐southern Great Xing'an Range, Northeast China

Abstract

Zircon U–Pb dating and whole‐rock geochemical analysis have been studied on the Late Jurassic volcanic rocks in the Hailisen area, Northeastern China, with the aim of constraining the tectonic evolution of the central‐southern Great Xing'an Range during the Late Jurassic. The volcanic rocks mainly consist of andesite from the Tamulangou Formation, and rhyolite and minor dacite from the Manketouebo Formation. The results of inductively coupled plasma‐mass spectrometry Zircon U–Pb dating for two andesites and one dacite indicate that they formed in the Late Jurassic (161–150 Ma). The mafic rocks are characteristic of low TiO2 (1.01–1.04 wt.%) and P2O5 (0.23–0.31 wt.%) contents, and high Al2O3 (17.19–20.18 wt.%) and CaO (6.69–7.45 wt.%) contents, and belong to the low‐K tholeiitic series. These mafic rocks are also characterized by moderately enriched light rare earth element (LREE) patterns and high abundances of Th, U, Zr, and Hf but negative Nb, Ta, and Ti anomalies. The felsic rocks are enriched in alkalis, Th, U, and LREEs; depleted in Ba, Sr, Nb, Ta, and Ti; and exhibit moderately LREE‐enriched patterns. These features indicate that the mafic volcanic rocks were likely formed by the partial melting of a lithospheric mantle that was metasomatized by subduction‐derived components, but the felsic rocks could derived by partial melting of a crustal source. The Tamulangou and Manketouebo formations have compositions of typical bimodal volcanism, an extensional environment, similar to a post‐orogenic setting, which might be related to the closure of Mongol–Okhotsk Ocean.

Identifying Early Carboniferous bimodal volcanic rocks and geochemical characteristics in the Atengtao Mountain, Yili Block (Chinese western Tianshan)

“…The SiO 2 contents of basaltic andesites in Dahalajunshan Formation span a range from 52.08 to 60.44 wt.%, whereas those of the rhyolites range from 72.50 to 76.78 wt.% (Table ), showing a sharp gap between 60.44% and 72.50% for SiO 2 content, thus displaying a typical bimodal feature. This kind of bimodal volcanic rocks with the mafic end‐member mainly consists of basaltic andesite and andesite, as well as the felsic end‐member consists of rhyolite and minor dacite, are widespread in the world (Gao et al, ; Liu et al, ; Mtoro, Maboko, & Manya, ; Xie, Mao, Li, Duan, & Yao, ; Zhang, Zhang, Tang, Wilde, & Hu, ; Zhu et al, ). The major element compositions are normalized to 100% before plotting in discrimination diagrams.…”

“…(d) Photomicrograph of rhyolite in cross-polarised light typical bimodal feature. This kind of bimodal volcanic rocks with the mafic end-member mainly consists of basaltic andesite and andesite, as well as the felsic end-member consists of rhyolite and minor dacite,are widespread in the world(Gao et al, 2017;Liu et al, 2017;Mtoro, Maboko, & Manya, 2009;Xie, Mao, Li, Duan, & Yao, 2011;Zhang, Zhang, Tang, Wilde, & Hu, 2008;Zhu et al, 2015). The major element compositions are normalized to 100% before plotting in discrimination diagrams.…”

Petrogenesis and tectonic implications of Late Mesozoic volcanic rocks in the northern and central Great Xing'an Range, NE China: Constraints from geochronology and geochemistry

“…This was achieved by using different times in the same stratum. For example, with the volcanic rocks of the Manitu and Manketouebo formations originated in the Late Jurassic-Early Cretaceous (Liu, Zhou, Tang, et al, 2017;Liu, Zhou, Wang, et al, 2018), which severely complicated the timing of the stratigraphic subdivisions of the Late Mesozoic volcanic rocks in F I G U R E 2 Detailed geological map of the study area showing the sampling locations [Colour figure can be viewed at wileyonlinelibrary.com] the NCGXR. The published new age data of the volcanic rocks suggest that previous stratigraphic assignments of the volcanic strata should be re-evaluated.…”

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

“…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].…”

“…Regional geological data show that previous geochronological, geochemical, and isotopic studies mainly focused on the northern and southern parts of the GXR [32,34,57,58,63], but few studies have focused on the central-southern segment [1,16,17,64]. The Ulanhot area, characterized by extensive intrusions (Figure 2), is affiliated with the central and southern part of GXR and located at the junction of the Xing'an block and the Songnen block, which is a favorable place to study the Early Cretaceous tectonic setting of GXR.…”