Spherulite in metamorphic rocks and its implication for metamorphism

Anping, Chen; Shi, Yonghong; XiaoYan, Zeng

doi:10.18654/1000-0569/2019.10.17

Cited by 2 publications

(2 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Precambrian metamorphic basement in the Daqingshan area is composed of supracrustal and plutonic rocks of different types and ages (Jin et al . 1991, 1992; Xu et al . 2002, 2005, 2007; Yang et al .…”

Section: Geological Backgroundmentioning

confidence: 99%

“…The Precambrian metamorphic basement in the Daqingshan area is composed of supracrustal and plutonic rocks of different types and ages (Jin et al 1991(Jin et al , 1992Xu et al 2002Xu et al , 2005Xu et al , 2007Yang et al 2003Yang et al , 2006. The supracrustal rocks were divided into the late Neoarchaean Sanggan Group, the late Neoarchaean Daqingshan Supracrustal Rocks, the early Palaeoproterozoic Lower Wulashan Group and the late Palaeoproterozoic Upper Wulashan Group (Fig.…”

Section: Geological Backgroundmentioning

confidence: 99%

See 1 more Smart Citation

Establishing the occurrence of late Neoarchaean – earliest Palaeoproterozoic magmatism in the Daqingshan area, northwestern North China Craton: SIMS U–Pb zircon dating, Lu–Hf and Sm–Nd isotopes and whole-rock geochemistry

Dong

Wilde

et al. 2023

Geol. Mag.

View full text Add to dashboard Cite

Daqingshan is located in the northwestern North China Craton where late Neoarchaean supracrustal rocks occur widely, but where magmatic zircon ages have rarely been reported for plutonic rocks. In this study, we report SIMS U–Pb zircon ages and Hf isotope, whole-rock element and Nd isotope compositions for 12 magmatic samples, including TTG, quartz monzonitic and monzogranitic gneisses, and meta-gabbroic and dioritic rocks. They have magmatic zircon ages of 2530–2469 Ma; some samples have ages of <2.48 Ga likely influenced by late Palaeoproterozoic tectonothermal events, making their ages less reliable. TTG gneisses have low Sr/Y and La/Yb ratios, with whole-rock ϵNd(t) and in situ magmatic zircon ϵHf(t) values of +1.2 to +2.4 and −1.1 to +6.2, respectively. Quartz monzonite and monzogranite gneisses and gabbroic to dioritic rocks have similar Nd–Hf isotope compositions to the TTG gneisses. The absence of zircon >2.6 Ga in the early Precambrian rocks suggests that the Sanggan Group may have formed in an oceanic environment, whereas the TTG rocks formed as a result of partial melting of the basaltic rocks of the Sanggan Group under relatively low-pressure conditions. Combined with previous studies, the main conclusions are that in the Daqingshan area, late Neoarchaean magmatism was widespread, the late Mesoarchaean – early Neoarchaean was an important period of juvenile continental crustal growth, and the late Neoarchaean supracrustal and plutonic rocks most likely formed in an arc environment. These are common signatures for Neoarchaean crustal evolution throughout much of the North China Craton, and also globally.

show abstract

Section: Geological Backgroundmentioning

confidence: 99%

Section: Geological Backgroundmentioning

confidence: 99%